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Document And Entity Information - USD ($) $ in Millions	12 Months Ended
Document And Entity Information - USD ($) $ in Millions	Sep. 30, 2011	Dec. 15, 2011	Mar. 31, 2011
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Sep. 30, 2011
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2011
Entity Registrant Name	ARROWHEAD RESEARCH CORP
Entity Central Index Key	0000879407
Current Fiscal Year End Date	--09-30
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		10,525,941
Entity Well-known Seasoned Issuer	No
Entity Public Float			$ 53
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No

Consolidated Balance Sheets - USD ($)	Sep. 30, 2011	Sep. 30, 2010
CURRENT ASSETS
Cash and cash equivalents	$ 7,507,389	$ 6,847,162
Trade receivable, net of allowance for doubtful accounts of $90,789 at September 30, 2010		58,864
Other receivables	1,608,382	871,819
Prepaid expenses and other current assets	110,818	353,930
Marketable securities	634,585
TOTAL CURRENT ASSETS	9,861,174	8,131,775
PROPERTY AND EQUIPMENT
Computers, office equipment and furniture	285,266	335,784
Research equipment	3,515	752,850
Software	77,020	150,445
Leasehold improvements		78,594
Property, Plant and Equipment, Gross, Total	365,801	1,317,673
Less: Accumulated depreciation and amortization	(340,364)	(1,176,404)
PROPERTY AND EQUIPMENT, NET	25,437	141,269
OTHER ASSETS
Rent deposit		34,735
Patents	1,731,211	2,046,836
Note Receivable, net	2,272,868
Derivative asset	161,125
Investment in Nanotope Inc., equity basis	1,649,748	1,812,927
Investment in Leonardo Biosystems Inc., at cost	187,000	187,000
TOTAL OTHER ASSETS	6,001,952	4,081,498
TOTAL ASSETS	15,888,563	12,354,542
CURRENT LIABILITIES
Accounts payable	576,809	681,563
Accrued expenses	864,511	494,736
Accrued payroll and benefits	195,649	191,425
Derivative liabilities	944,980	2,408,522
Note payable		500,000
TOTAL CURRENT LIABILITIES	2,581,949	4,276,246
LONG-TERM LIABILITIES
Other non-current liabilities	135,660
Note payable	606,786
TOTAL LONG-TERM LIABILITIES	742,446
Commitments and contingencies
STOCKHOLDERS' EQUITY
Preferred stock, $0.001 par value; 5,000,000 shares authorized; no shares issued or outstanding
Common stock, $0.001 par value; 145,000,000 shares authorized; 8,642,286 and 7,172,014 shares issued and outstanding as of September 30, 2011 and September 30, 2010, respectively	86,423	71,735
Additional paid-in capital	127,476,435	119,716,834
Subscription receivable	(900,000)
Accumulated deficit during the development stage	(113,871,752)	(110,742,867)
Total Arrowhead Research Corporation stockholders' equity	12,791,106	9,045,702
Noncontrolling interest	(226,938)	(967,406)
TOTAL STOCKHOLDERS' EQUITY	12,564,168	8,078,296
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 15,888,563	$ 12,354,542

Consolidated Balance Sheets (Parenthetical) - USD ($)	Sep. 30, 2011	Sep. 30, 2010
Consolidated Balance Sheets [Abstract]
Trade receivable, allowance for doubtful accounts		$ 90,789
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	145,000,000	145,000,000
Common stock, shares issued	8,642,286	7,172,014
Common stock, shares outstanding	8,642,286	7,172,014

Consolidated Statements Of Operations - USD ($)	12 Months Ended		101 Months Ended
Consolidated Statements Of Operations - USD ($)	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011
Consolidated Statements Of Operations [Abstract]
REVENUE	$ 296,139		$ 3,991,959
OPERATING EXPENSES
Salaries	1,408,366	$ 1,146,394	19,977,209
General and administrative expenses	3,821,550	2,490,725	25,590,815
Research and development	3,277,760	529,601	40,428,729
Stock-based compensation	1,376,921	1,424,293	12,340,064
Patent amortization	241,808	241,808	1,781,944
TOTAL OPERATING EXPENSES	10,126,405	5,832,821	100,118,761
OPERATING LOSS	(9,830,266)	(5,832,821)	(96,126,802)
OTHER INCOME (EXPENSE)
Loss on equity of investments - Nanotope	(163,180)	(219,540)	(723,253)
Gain on sale of stock in subsidiary			2,292,800
Gain/(loss) on sale of fixed assets, net		1,772	(127,088)
Realized and unrealized gain (loss) on marketable securities	(261,219)		121,045
Interest income (expense), net	86,530	(22,783)	2,714,478
Change in value of derivatives	1,133,127	1,761,385	2,894,512
Other income	250,000		250,000
TOTAL OTHER INCOME (EXPENSE)	1,045,258	1,520,834	7,422,494
LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	(8,785,008)	(4,311,987)	(88,704,308)
Provision for income taxes
LOSS FROM CONTINUING OPERATIONS	(8,785,008)	(4,311,987)	(88,704,308)
Income (loss) from discontinued operations	1,373,396	(2,645,051)	(47,546,562)
Gain on disposal of discontinued operations	3,919,213		4,708,588
NET INCOME (LOSS) FROM DISCONTINUED OPERATIONS	5,292,609	(2,645,051)	(42,837,974)
NET LOSS	(3,492,399)	(6,957,038)	(131,542,282)
Net (income) loss attributable to noncontrolling interests	363,514	1,182,990	17,834,490
NET LOSS ATTRIBUTABLE TO ARROWHEAD	$ (3,128,885)	$ (5,774,048)	$ (113,707,792)
Earnings per share - basic:
Income (loss) from continuing operations attributable to Arrowhead common shareholders	$ (1.18)	$ (0.49)
Income (loss) from discontinued operations attributable to Arrowhead common shareholders	0.74	(0.41)
Net loss attributable to Arrowhead shareholders	$ (0.44)	$ (0.90)
Weighted average shares outstanding	7,181,121	6,434,245
Earnings per share - diluted:
Income (loss) from continuing operations attributable to Arrowhead common shareholders	$ (1.08)	$ (0.49)
Income (loss) from discontinued operations attributable to Arrowhead common shareholders	0.68	(0.41)
Net loss attributable to Arrowhead shareholders	$ (0.40)	$ (0.90)
Weighted average shares outstanding	7,830,407	6,434,245

Consolidated Statement Of Stockholders' Equity - USD ($)	Issued For Cash At $10.00 Per Unit [Member] Common Stock [Member]	Issued For Cash At $10.00 Per Unit [Member] Additional Paid-In Capital [Member]	Issued For Cash At $10.00 Per Unit [Member]	Issued For Marketable Securities At $10.00 Per Unit [Member] Common Stock [Member]	Issued For Marketable Securities At $10.00 Per Unit [Member] Additional Paid-In Capital [Member]	Issued For Marketable Securities At $10.00 Per Unit [Member]	Issued For Cash At $15.00 Per Unit [Member] Common Stock [Member]	Issued For Cash At $15.00 Per Unit [Member] Additional Paid-In Capital [Member]	Issued For Cash At $15.00 Per Unit [Member]	Stock Issuance Cost Charged To Additional Paid In Capital [Member] Additional Paid-In Capital [Member]	Stock Issuance Cost Charged To Additional Paid In Capital [Member]	Arrowheads Increase In Proportionate Share Of Insert Therapeutics Equity [Member] Additional Paid-In Capital [Member]	Arrowheads Increase In Proportionate Share Of Insert Therapeutics Equity [Member]	Arrowheads Increase In Proportionate Share Of Calando's Equity [Member] Additional Paid-In Capital [Member]	Arrowheads Increase In Proportionate Share Of Calando's Equity [Member]	Issued as a Gift for $10.90 Per Share [Member] Common Stock [Member]	Issued as a Gift for $10.90 Per Share [Member] Additional Paid-In Capital [Member]	Issued as a Gift for $10.90 Per Share [Member]	Issued As Stock Issuance Cost At $15.00 Per Unit [Member] Common Stock [Member]	Issued As Stock Issuance Cost At $15.00 Per Unit [Member] Additional Paid-In Capital [Member]	Issued As Stock Issuance Cost At $15.00 Per Unit [Member]	Exercised At $2.00 Per Share [Member] Common Stock [Member]	Exercised At $2.00 Per Share [Member] Additional Paid-In Capital [Member]	Exercised At $2.00 Per Share [Member]	Exercised At $10.00 Per Share [Member] Common Stock [Member]	Exercised At $10.00 Per Share [Member] Additional Paid-In Capital [Member]	Exercised At $10.00 Per Share [Member]	Exercised At $15.00 Per Share [Member] Common Stock [Member]	Exercised At $15.00 Per Share [Member] Additional Paid-In Capital [Member]	Exercised At $15.00 Per Share [Member]	Issued To Purchase Insert Therapeutics Share At $39.80 Per Share [Member] Common Stock [Member]	Issued To Purchase Insert Therapeutics Share At $39.80 Per Share [Member] Additional Paid-In Capital [Member]	Issued To Purchase Insert Therapeutics Share At $39.80 Per Share [Member]	Issued At $48.80 Per Share [Member] Common Stock [Member]	Issued At $48.80 Per Share [Member] Additional Paid-In Capital [Member]	Issued At $48.80 Per Share [Member]	Issued At $38.40 Per Share [Member] Common Stock [Member]	Issued At $38.40 Per Share [Member] Additional Paid-In Capital [Member]	Issued At $38.40 Per Share [Member]	Issued At $35.00 Per Share [Member] Common Stock [Member]	Issued At $35.00 Per Share [Member] Additional Paid-In Capital [Member]	Issued At $35.00 Per Share [Member]	Issued At $59.10 Per Share [Member] Common Stock [Member]	Issued At $59.10 Per Share [Member] Additional Paid-In Capital [Member]	Issued At $59.10 Per Share [Member]	Issued To Purchase Calando Pharmaceuticals Inc At $51.70 Per Share [Member] Common Stock [Member]	Issued To Purchase Calando Pharmaceuticals Inc At $51.70 Per Share [Member] Additional Paid-In Capital [Member]	Issued To Purchase Calando Pharmaceuticals Inc At $51.70 Per Share [Member]	Issued At $57.80 Per Share [Member] Common Stock [Member]	Issued At $57.80 Per Share [Member] Additional Paid-In Capital [Member]	Issued At $57.80 Per Share [Member]	Issued For Purchase Of Carbon Nanotechnologies Inc At $37.70 Per Share [Member] Common Stock [Member]	Issued For Purchase Of Carbon Nanotechnologies Inc At $37.70 Per Share [Member] Additional Paid-In Capital [Member]	Issued For Purchase Of Carbon Nanotechnologies Inc At $37.70 Per Share [Member]	Issued At Approximately $18.00 Per Share Net [Member] Common Stock [Member]	Issued At Approximately $18.00 Per Share Net [Member] Additional Paid-In Capital [Member]	Issued At Approximately $18.00 Per Share Net [Member]	Issued At $27.20 Per Share To Rice University [Member] Common Stock [Member]	Issued At $27.20 Per Share To Rice University [Member] Additional Paid-In Capital [Member]	Issued At $27.20 Per Share To Rice University [Member]	Issued At $28.30 Per Share To Purchase Shares Of Unidym Inc [Member] Common Stock [Member]	Issued At $28.30 Per Share To Purchase Shares Of Unidym Inc [Member] Additional Paid-In Capital [Member]	Issued At $28.30 Per Share To Purchase Shares Of Unidym Inc [Member]	Issued At $29.50 per Share To Purchase MASA Energy LLC [Member] Common Stock [Member]	Issued At $29.50 per Share To Purchase MASA Energy LLC [Member] Additional Paid-In Capital [Member]	Issued At $29.50 per Share To Purchase MASA Energy LLC [Member]	Issued At $21.90 Per Share To Unidym For The Acquisition Of Nanoconduction [Member] Common Stock [Member]	Issued At $21.90 Per Share To Unidym For The Acquisition Of Nanoconduction [Member] Additional Paid-In Capital [Member]	Issued At $21.90 Per Share To Unidym For The Acquisition Of Nanoconduction [Member]	Issued At $21.80 Per Share [Member] Common Stock [Member]	Issued At $21.80 Per Share [Member] Additional Paid-In Capital [Member]	Issued At $21.80 Per Share [Member]	Issued At $5.50 Per Share To Unidym Stockholder In Exchange For Unidym's Shares [Member] Common Stock [Member]	Issued At $5.50 Per Share To Unidym Stockholder In Exchange For Unidym's Shares [Member] Additional Paid-In Capital [Member]	Issued At $5.50 Per Share To Unidym Stockholder In Exchange For Unidym's Shares [Member]	Issued At $5.20 Per Share To TEL Ventures In Exchange For Unidym's Shares [Member] Common Stock [Member]	Issued At $5.20 Per Share To TEL Ventures In Exchange For Unidym's Shares [Member] Additional Paid-In Capital [Member]	Issued At $5.20 Per Share To TEL Ventures In Exchange For Unidym's Shares [Member]	Issued At $3.00 Per Share [Member] Common Stock [Member]	Issued At $3.00 Per Share [Member] Additional Paid-In Capital [Member]	Issued At $3.00 Per Share [Member]	Issued At $6.30 Per Share [Member] Common Stock [Member]	Issued At $6.30 Per Share [Member] Additional Paid-In Capital [Member]	Issued At $6.30 Per Share [Member]	Issued At $13.12 Per Share [Member] Common Stock [Member]	Issued At $13.12 Per Share [Member] Additional Paid-In Capital [Member]	Issued At $13.12 Per Share [Member]	Issued At $3.80 Per Share [Member] Common Stock [Member]	Issued At $3.80 Per Share [Member] Additional Paid-In Capital [Member]	Issued At $3.80 Per Share [Member]	Issuance Of Common Stock For Subscription [Member] Subscription Receivable [Member]	Issuance Of Common Stock For Subscription [Member] Additional Paid-In Capital [Member]	Series D Preferred Stock Issued For Subscription In Unidym [Member] Subscription Receivable [Member]	Series D Preferred Stock Issued For Subscription In Unidym [Member] Additional Paid-In Capital [Member]	Issued To Unidym Stockholders In Exchange For Unidym's Shares [Member] Common Stock [Member]	Issued To Unidym Stockholders In Exchange For Unidym's Shares [Member] Additional Paid-In Capital [Member]	Issued To Unidym Stockholders In Exchange For Unidym's Shares [Member] Noncontrolling Interest [Member]	Issued To Calando Stockholders In Exchange For Calando's Shares [Member] Common Stock [Member]	Issued To Calando Stockholders In Exchange For Calando's Shares [Member] Additional Paid-In Capital [Member]	Issued To Calando Stockholders In Exchange For Calando's Shares [Member] Noncontrolling Interest [Member]	Subscription Receivable [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Noncontrolling Interest [Member]	Total
Stock issued during period, value, new issues	$ 475	$ 474,525	$ 475,000	$ 500	$ 499,500	$ 500,000	$ 6,609	$ 9,906,573	$ 9,913,182							$ 163	$ 162,587	$ 162,750	$ 356	$ 533,988	$ 534,344																																																																																	$ 706	$ (151,175)			$ (150,469)
Stock issued during period, shares, new issues	47,500			50,000			660,879									15,000			35,623																																																																																			70,553
Stock issuance cost charged to additional paid-in capital										$ (96,500)	$ (96,500)																																																																																												(991,318)			(991,318)
Net loss attributable to Arrowhead																																																																																																								(2,528,954)	1,777,699	(751,255)
Stock issued during period, value, stock options exercised																						$ 75	$ 14,925	$ 15,000	$ 6	$ 5,994	$ 6,000																																																																											$ 75	14,925			15,000
Stock issued during period, shares, stock options exercised																						7,500			600																																																																													7,500
Adjustments to additional paid in capital, share-based compensation, requisite service period recognition, value																																																																																																							175,653			175,653
Stockholders' equity, including portion attributable to noncontrolling interest, ending balance at Sep. 30, 2004																																																																																																						$ 13,645	12,059,997	(2,624,192)	1,777,699	11,227,149
Shares, issued at Sep. 30, 2004																																																																																																						1,363,155
Stock issued during period, value, new issues																									$ 25	$ 24,975	$ 25,000	$ 13,813	$ 20,705,522	$ 20,719,335	$ 502	$ 1,999,498	$ 2,000,000																																																																					$ 12	49,988			50,000
Stock issued during period, shares, new issues																									2,500			1,381,289			50,226																																																																							1,250
Net loss attributable to Arrowhead																																																																																																								(6,854,918)	121,491	(6,733,427)
Adjustments to additional paid in capital, share-based compensation, requisite service period recognition, value																																																																																																							508,513			508,513
Adjustments to additional paid in capital, reallocation of noncontrolling interest																																																																																																							230,087			230,087
Stockholders' equity, including portion attributable to noncontrolling interest, ending balance at Sep. 30, 2005																																																																																																						$ 27,997	35,578,580	(9,479,110)	1,899,190	28,026,657
Shares, issued at Sep. 30, 2005																																																																																																						2,798,419
Stock issued during period, value, new issues																																		$ 205	$ 999,795	$ 1,000,000	$ 15	$ 57,585	$ 57,600	$ 5,590	$ 19,539,410	$ 19,545,000	$ 25	$ 149,975	$ 150,000	$ 208	$ 1,077,125	$ 1,077,333
Stock issued during period, shares, new issues																																		20,485			1,500			559,000			2,536			20,838
Net loss attributable to Arrowhead																																																																																																								(18,997,209)	(964,752)	(19,961,961)
Stock issued during period, value, stock options exercised																																																																																																						$ 116	341,421			341,537
Stock issued during period, shares, stock options exercised																																																																																																						11,579
Adjustments to additional paid in capital, share-based compensation, requisite service period recognition, value																																																																																																							1,369,478			1,369,478
Stockholders' equity, including portion attributable to noncontrolling interest, ending balance at Sep. 30, 2006																																																																																																						$ 34,156	59,113,369	(28,476,319)	934,438	31,605,644
Shares, issued at Sep. 30, 2006																																																																																																						3,414,359
Stock issued during period, value, new issues																																																	$ 2,849	$ 15,149,366	$ 15,152,215	$ 1,431	$ 5,398,569	$ 5,400,000
Stock issued during period, shares, new issues																																																	284,945			143,122
Net loss attributable to Arrowhead																																																																																																								(29,931,118)	(781,829)	(30,712,947)
Stock issued during period, value, stock options exercised																																																																																																						$ 186	434,541			434,727
Stock issued during period, shares, stock options exercised																																																																																																						18,616
Adjustments to additional paid in capital, share-based compensation, requisite service period recognition, value																																																																																																							2,175,544			2,175,544
Adjustments to additional paid in capital, reallocation of noncontrolling interest												$ 2,401,394	$ 2,401,394
Stockholders' equity, including portion attributable to noncontrolling interest, ending balance at Sep. 30, 2007																																																																																																						$ 38,622	84,672,783	(58,407,437)	152,609	26,456,577
Shares, issued at Sep. 30, 2007																																																																																																						3,861,042
Stock issued during period, value, new issues																																																							$ 3,867	$ 6,956,718	$ 6,960,585	$ 50	$ 135,950	$ 136,000	$ 71	$ 199,929	$ 200,000	$ 105	$ 309,895	$ 310,000	$ 114	$ 249,886	$ 250,000	$ 15	$ 32,685	$ 32,700
Stock issued during period, shares, new issues																																																							386,399			5,000			7,055			10,505			11,416			1,500
Net loss attributable to Arrowhead																																																																																																								(27,089,030)	(152,609)	(27,241,639)
Stock issued during period, value, stock options exercised																																																																																																						$ 106	289,921			290,027
Stock issued during period, shares, stock options exercised																																																																																																						10,536
Adjustments to additional paid in capital, share-based compensation, requisite service period recognition, value																																																																																																							3,187,397			3,187,397
Adjustments to additional paid in capital, reallocation of noncontrolling interest																																																																																																							1,720,962			1,720,962
Stockholders' equity, including portion attributable to noncontrolling interest, ending balance at Sep. 30, 2008																																																																																																						$ 42,950	97,756,126	(85,496,467)		12,302,609
Shares, issued at Sep. 30, 2008																																																																																																						4,293,452
Stock issued during period, value, new issues																																																																									$ 2,059	$ 1,131,617	$ 1,133,676	$ 2,222	$ 1,156,111	$ 1,158,333	$ 9,197	$ 2,749,796	$ 2,758,993
Stock issued during period, shares, new issues																																																																									205,839			222,222			919,664
Reclassification of former Unidym mezzanine debt to equity																																																																																																							2,000,000			2,000,000
Net loss attributable to Arrowhead																																																																																																								(19,308,392)		(19,308,392)
Adjustments to additional paid in capital, share-based compensation, requisite service period recognition, value																																																																																																							2,676,170			2,676,170
Adjustments to additional paid in capital, reallocation of noncontrolling interest														$ 2,120,250	$ 2,120,250																																																																																								16,297			16,297
Issuance of preferred stock in subsidiary																																																																																													$ (300,000)	$ 300,000
Amortization of discount on Unidym Series D Preferred Stock																																																																																																							163,960	(163,960)
Stockholders' equity, including portion attributable to noncontrolling interest, ending balance at Sep. 30, 2009																																																																																																					(300,000)	$ 56,428	110,070,327	(104,968,819)		4,857,936
Shares, issued at Sep. 30, 2009																																																																																																						5,641,177
Stock issued during period, value, new issues																																																																																		$ 5,083	$ 3,217,813	$ 3,222,896	$ 6,593	$ 3,692,078	$ 3,698,671								$ 153	$ (1,435)	$ 1,282	$ 1,220	$ (160,667)	$ 159,447		$ 2,251	1,063,600		200	1,066,051
Stock issued during period, shares, new issues																																																																																		508,343			659,299										15,318			122,000				225,189
Net loss attributable to Arrowhead																																																																																																								(5,774,048)	(1,182,990)	(6,957,038)
Stock issued during period, value, stock options exercised																																																																																																						$ 7	7,624			7,631
Stock issued during period, shares, stock options exercised																																																																																																						688
Adjustments to additional paid in capital, share-based compensation, requisite service period recognition, value																																																																																																							1,582,149			1,582,149
Adjustments to additional paid in capital, reallocation of noncontrolling interest																																																																																																							245,345		54,655	300,000
Issuance of preferred stock in subsidiary																																																																																																					300,000					300,000
Stockholders' equity, including portion attributable to noncontrolling interest, ending balance at Sep. 30, 2010																																																																																																						$ 71,735	119,716,834	(110,742,867)	(967,406)	8,078,296
Shares, issued at Sep. 30, 2010																																																																																																						7,172,014
Net loss attributable to Arrowhead																																																																																																										(5,774,048)
Stock issued during period, value, new issues																																																																																								$ 14,574	$ 4,629,110	$ 4,643,684	$ (900,000)	$ 900,000										$ 87	43,192			43,279
Stock issued during period, shares, new issues																																																																																								1,458,917														8,656
Net loss attributable to Arrowhead																																																																																																								(3,128,885)	(363,514)	(3,492,399)
Stock issued during period, value, stock options exercised																																																																																																						$ 27	13,857			13,884
Stock issued during period, shares, stock options exercised																																																																																																						2,700
Adjustments to additional paid in capital, share-based compensation, requisite service period recognition, value																																																																																																							1,404,640			1,404,640
Adjustments to additional paid in capital, reallocation of noncontrolling interest																																																																																																							(849,707)		849,707
Issuance of preferred stock in subsidiary																																																																																																							1,618,509			1,618,509
Stockholders' equity, including portion attributable to noncontrolling interest, ending balance at Sep. 30, 2011																																																																																																					(900,000)	$ 86,423	127,476,435	(113,871,752)	(226,938)	12,564,168
Shares, issued at Sep. 30, 2011																																																																																																						8,642,286
Divestiture of Unidym																																																																																																									$ 254,275	254,275
Net loss attributable to Arrowhead																																																																																																										$ (3,128,885)

Consolidated Statement Of Stockholders' Equity (Parenthetical) - $ / shares	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009	Sep. 30, 2008	Sep. 30, 2007	Sep. 30, 2006	Sep. 30, 2005	Sep. 30, 2004	Sep. 30, 2003
Issued For Cash At $0.01 Per Unit [Member]
Common stock & warrants issued for cash, price per unit									$ 0.01
Issued For Cash At $10.00 Per Unit [Member]
Common stock & warrants issued for cash, price per unit								$ 10	$ 10
Issued For Marketable Securities At $10.00 Per Unit [Member]
Common stock & warrants issued for cash, price per unit								10
Issued For Cash At $15.00 Per Unit [Member]
Common stock & warrants issued for cash, price per unit								15
Issued as a Gift for $10.90 Per Share [Member]
Common stock & warrants issued for cash, price per unit								10.9
Issued As Stock Issuance Cost At $15.00 Per Unit [Member]
Common stock & warrants issued for cash, price per unit								15
Exercised At $2.00 Per Share [Member]
Exercise of stock options, price per share								2
Exercised At $10.00 Per Share [Member]
Exercise of stock options, price per share							$ 10	$ 10
Exercised At $15.00 Per Share [Member]
Exercise of stock options, price per share							15
Issued At $48.80 Per Share [Member]
Common stock issued, par value per share						$ 48.8
Issued To Purchase Insert Therapeutics Share At $39.80 Per Share [Member]
Common stock issued, par value per share							$ 39.8
Issued At $38.40 Per Share [Member]
Common stock issued, par value per share						38.4
Issued At $35.00 Per Share [Member]
Common stock issued, par value per share						35
Issued At $59.10 Per Share [Member]
Common stock issued, par value per share						59.1
Issued To Purchase Calando Pharmaceuticals Inc At $51.70 Per Share [Member]
Common stock issued, par value per share						$ 51.7
Issued At $57.80 Per Share [Member]
Common stock issued, par value per share					$ 57.8
Issued For Purchase Of Carbon Nanotechnologies Inc At $37.70 Per Share [Member]
Common stock issued, par value per share					$ 37.7
Issued At Approximately $18.00 Per Share Net [Member]
Common stock issued, par value per share				$ 18
Issued At $27.20 Per Share To Rice University [Member]
Common stock issued, par value per share				27.2
Issued At $28.30 Per Share To Purchase Shares Of Unidym Inc [Member]
Common stock issued, par value per share				28.3
Issued At $29.50 per Share To Purchase MASA Energy LLC [Member]
Common stock issued, par value per share				29.5
Issued At $21.90 Per Share To Unidym For The Acquisition Of Nanoconduction [Member]
Common stock issued, par value per share				21.9
Issued At $21.80 Per Share [Member]
Common stock issued, par value per share				$ 21.8
Issued At $5.50 Per Share To Unidym Stockholder In Exchange For Unidym's Shares [Member]
Common stock issued, par value per share			$ 5.5
Issued At $5.20 Per Share To TEL Ventures In Exchange For Unidym's Shares [Member]
Common stock issued, par value per share			5.2
Issued At $3.00 Per Share [Member]
Common stock issued, par value per share			$ 3
Issued At $6.30 Per Share [Member]
Common stock issued, par value per share		$ 6.3
Issued At $13.12 Per Share [Member]
Common stock issued, par value per share		$ 13.12
Issued At $3.80 Per Share [Member]
Common stock issued, par value per share	$ 3.80

Consolidated Statements Of Cash Flows - USD ($)	12 Months Ended		101 Months Ended
Consolidated Statements Of Cash Flows - USD ($)	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ (3,492,399)	$ (6,957,038)	$ (131,542,282)
Net (income) loss attributable to noncontrolling interests	363,514	1,182,990	17,834,490
Net loss attributable to Arrowhead	(3,128,885)	(5,774,048)	(113,707,792)
(Income) loss from discontinued operations	(5,292,609)	2,645,051	42,837,974
Realized and unrealized (gain) loss on investments	261,218		(821,045)
(Gain) loss from sale of subsidiary			(306,344)
Loss on sale/donation of fixed assets		(1,772)	127,088
Stock issued as gift			298,750
Stock issued for professional services	193,885		442,882
Stock issued for in-process research and development			13,166,347
Change in value of derivatives	(1,133,127)	(1,761,385)	(2,894,512)
Purchased in-process research and development - Nanoconduction			2,685,208
Stock-based compensation	1,376,921	1,424,293	12,340,064
Depreciation and amortization	267,977	277,650	5,660,311
Amortization (accretion) of note discounts, net	(7,938)		(7,938)
Gain on sale of stock in subsidiary			(2,292,800)
Non-cash (gain) loss from equity investment	163,180	219,540	723,253
Noncontrolling interest	(363,514)	(1,182,990)	(17,834,490)
Gain on renegotiation of accrued severance			(726,500)
Changes in operating assets and liabilities:
Receivables			(62,815)
Other receivables	(736,253)	(872,128)	(1,604,963)
Prepaid expenses	99,006	110,152	(142,568)
Other current assets	18,473	(114,833)	(96,360)
Deposits		60,105	(36,795)
Accounts payable	157,079	(203,253)	206,434
Accrued expenses	452,843	110,873	534,540
Accrued severance and other liabilities	15,751	7,556	974,365
NET CASH USED IN OPERATING ACTIVITIES OF CONTINUING OPERATIONS	(7,655,993)	(5,053,417)	(60,537,706)
CASH FLOWS FROM INVESTING ACTIVITIES OF CONTINUING OPERATIONS:
Purchase of marketable securities - US Treasury Bills			(18,575,915)
Purchase of property and equipment	(9,674)		(3,565,599)
Purchase of MASA Energy, LLC			(250,000)
Minority equity investment			(2,000,000)
Cash paid for interest in Insert			(10,150,000)
Cash obtained from interest in Insert			10,529,594
Proceeds from sale of marketable securities - US Treasury Bills			18,888,265
Proceeds from sale of investments	1,534,687		2,804,600
Proceeds from sale of subsidiaries			359,375
Proceeds from sale of fixed assets			142,375
Payment for patents			(303,440)
Restricted cash			50,773
Cash transferred in sale of subsidiary	(1,700,398)		(1,700,398)
NET CASH USED IN INVESTING ACTIVITIES OF CONTINUING OPERATIONS	(175,385)		(3,770,370)
CASH FLOWS FROM FINANCING ACTIVITIES OF CONTINUING OPERATIONS:
Proceeds from issuance of Calando debt			2,516,467
Proceeds from sale of stock in subsidiary	1,718,932		20,894,100
Proceeds from issuance of common stock and warrants, net	4,507,389	12,165,156	95,294,780
NET CASH PROVIDED BY FINANCING ACTIVITIES OF CONTINUING OPERATIONS	6,226,321	12,165,156	118,705,347
Cash flows from discontinued operations:
Operating cash flows	2,265,284	(2,645,860)	(46,003,507)
Investing cash flows		487,593	790,625
Financing cash flows		(126,534)	(1,677,000)
Net cash provided by (used in) discontinued operations:	2,265,284	(2,284,801)	(46,889,882)
NET INCREASE IN CASH	660,227	4,826,938	7,507,389
CASH AT BEGINNING OF PERIOD	6,847,162	2,020,224
CASH AT END OF PERIOD	7,507,389	$ 6,847,162	7,507,389
Supplementary disclosures:
Interest paid	105,000		230,419
Taxes paid	$ 742,500		$ 742,500

Consolidated Statements Of Cash Flows (Parenthetical) - USD ($)	Nov. 30, 2010	Sep. 30, 2010	Mar. 31, 2010	Feb. 28, 2010	Sep. 30, 2009	Sep. 28, 2009	Sep. 22, 2009	Jun. 25, 2009	Jun. 11, 2009	Aug. 08, 2008	Apr. 29, 2008	Apr. 23, 2008	Apr. 20, 2007	Mar. 31, 2006	Mar. 23, 2005
Common stock, shares issued		7,172,014
Common stock value		$ 71,735
Warrants exercised			24,788
Stock issued against warrants			12,870
Insert Therapeutics, Inc [Member]
Purchase of common shares															7,375,000
Common stock, shares issued															50,226
Common stock value															$ 2,000,000
Calando Pharmaceuticals, Inc [Member]
Purchase of common shares	2,850,000			200,000										964,000
Common stock, shares issued	114,000			8,000										20,838
Common stock value	$ 706,800													$ 1,077,333
Value of common stock purchased														1,928,000
Stock purchased by cash														$ 850,667
Warrants issued	24,000			2,400
Warrants purchased	600,000			60,000
Common stock exercise value				$ 5.00
Unidym, Inc [Member]
Purchase of common shares												200,000
Common stock, shares issued						64,227						7,054
Common stock value						$ 398,209
Value of common stock purchased												$ 200,000
MASA Energy LLC [Member]
Common stock, shares issued											10,504
Common stock value											$ 310,000
Value of common stock purchased											560,000
Stock purchased by cash											$ 250,000
Nanoconduction, Inc [Member]
Common stock, shares issued										11,411
Common stock value										$ 250,000
Series E Preferred Stock [Member] \| Carbon Nanotechnologies, Inc [Member]
Common stock, shares issued													143,122
Common stock value													$ 5,400,000
Series A Preferred Stock [Member] \| Calando Pharmaceuticals, Inc [Member]
Purchase of common shares		1,562.5
Warrants issued		390,625
Common stock exercise value		$ 5.00
Series A Preferred Stock [Member] \| Unidym, Inc [Member]
Purchase of common shares						5,574
Common stock, shares issued							9,149		132,462
Common stock value							$ 46,662		$ 688,802
Series C Preferred Stock [Member] \| Unidym, Inc [Member]
Purchase of common shares						636,699
Common stock, shares issued	15,317							194,444
Common stock value	$ 47,485							$ 972,222
Series C-1 Preferred Stock [Member] \| Unidym, Inc [Member]
Common stock, shares issued					27,777
Common stock value					$ 186,111

Organization And Significant Accounting Policies	12 Months Ended
Organization And Significant Accounting Policies	Sep. 30, 2011
Organization And Significant Accounting Policies [Abstract]
Organization And Significant Accounting Policies	NOTE 1. *ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES* Nature of Business and Going Concern Arrowhead Research Corporation is a nanomedicine company developing innovative therapies at the interface of biology and nanoengineering to cure disease and improve human health. Arrowhead has one of the most advanced and broadest technology platforms for therapeutics based on RNA interference (RNAi), including access to five different RNAi delivery systems and the three primary small interfering RNA (siRNA) structures in commercial development for RNAi therapeutics. This broad technology platform enables optimization of siRNA therapeutic candidates for delivery based on siRNA chemistry, tissue type, disease state, and target [gene] and siRNA type and chemistry on a target-by-target basis. Arrowhead is leveraging its in house R&D expertise and capabilities, as well as a broad intellectual property portfolio for RNAi therapeutics, to attract development partnerships with other pharmaceutical and biotech companies committed to bringing RNAi therapeutics to market, as well as continuing the preclinical and clinical development its own clinical candidates. Arrowhead's non-RNAi development programs include a unique therapeutic candidate that shows promise for the treatment of obesity and advanced bioactive materials for the regeneration of injured tissues. Arrowhead operates a wholly-owned subsidiary, Arrowhead Madison, which is focused on the development of RNAi therapeutics, two majority owned subsidiaries, Calando, a leader in delivering small interfering RNAs for gene silencing, and Ablaris, an anti-obesity therapeutics company, and has minority investments in Nanotope, a regenerative medicine company and Leonardo, a multistage drug delivery company. Liquidity Arrowhead has historically financed its operations through the sale of securities of Arrowhead and its Subsidiaries. Development activities at our Subsidiaries has required significant capital investment since the Company's inception and we expect our current portfolio companies to continue to require cash investment in fiscal 2012 and beyond to continue development. At September 30, 2011, the Company had $7.5 million in cash to fund operations. During the year ended September 30, 2011, the Company's cash position increased by $0.7 million, primarily due to the issuance of Common Stock on September 30, 2011. This financing generated $6.0 million of which $4.4 million was received in fiscal 2011, while the balance is to be received in fiscal 2012. This inflow was mostly offset by operational spending at Arrowhead, Calando and Ablaris during fiscal 2011. In January 2011, Arrowhead sold its ownership interest in Unidym; therefore the cash burn associated with Unidym ceased in January 2011. As a result of the sale of Unidym, the Company received $2.5 million in stock of the acquirer, Wisepower Co. Ltd. ("Wisepower") and a $2.5 million convertible bond from Wisepower, of which approximately $200,000 is owed to a third party, who was a minority investor in Unidym. As of September 30, 2011, the Company sold approximately 60% of the stock for approximately $1.5 million. The remaining shares were sold in October 2011, generating proceeds of $0.5 million. The convertible bond with a face value of $2.5 million, is convertible into Wisepower common stock beginning on January 17, 2012 at a price of $2.00 per share, and can be redeemed on January 17, 2013, and at which time would represent an additional source of liquidity for the company. In October 2011, the Company raised an additional $3.9 million through the issuance of preferred stock and Common Stock. The Company also entered into a facility whereby it has the ability to draw capital up to $15 million, and may do so depending on cash needs and market conditions. On October 21, 2011, Arrowhead completed the acquisition of certain RNAi assets from Hoffmann-La Roche Inc. and F Hoffmann-La Roche Ltd., including intellectual property and a research and development facility based in Madison, Wisconsin. At the time of the acquisition, the facility had 41 employees. Due to the costs associated with the facility, including personnel costs, rent, research and development expenses, and other costs, it is expected that cash expenses will increase significantly in 2012 and beyond as the Company accelerates its preclinical and clinical development efforts. Based upon the Company's cash on hand, other sources of liquidity, as described above, and based upon the Company's operating plan, the Company's management anticipates that the Company will be able to satisfy the cash requirements of its operations through at least the next twelve months. The Company anticipates that further equity financings, and/or asset sales and license agreements will be necessary to continue to fund operations in the future. Summary of Significant Accounting Policies Principles of Consolidation—The consolidated financial statements include the accounts of Arrowhead and its Subsidiaries, Calando, Ablaris, Tego, Agonn, and until its disposition in January 2011, Unidym. Prior to April 2008, Arrowhead's Subsidiaries included Insert Therapeutics, Inc. ("Insert"), which was merged with Calando in April 2008. The merged entity is majority-owned by Arrowhead and continues to operate under the name of Calando. On January 17, 2011, Arrowhead sold its interests in Unidym to Wisepower, and on December 23, 2009, Tego completed a sale of its assets to Luna Innovations, Inc. Unidym and Tego results are included in the Income (Loss) from Discontinued Operations. Income (Loss) from Discontinued Operations also includes Aonex Technologies, Inc. ("Aonex"), sold in May 2008 and Nanotechnica, Inc. ("Nanotechnica"), dissolved in June 2005. All significant intercompany accounts and transactions are eliminated in consolidation, and noncontrolling interests are accounted for in the Company's financial statements. Basis of Presentation and Use of Estimates—The preparation of financial statements in conformity with generally accepted accounting principles requires management to make estimates and assumptions that affect the amounts reported in the accompanying financial statements. Significant estimates made in preparing these financial statements include valuing the stock of the Subsidiaries, assumptions to calculate stock-based compensation expense, allowance for doubtful accounts, deferred tax asset valuation allowance, derivative assets and liabilities, noncontrolling interest and useful lives for depreciable and amortizable assets. Actual results could differ from those estimates. Additionally, certain reclassifications have been made to prior period financial statements to conform to the current period presentation. In the opinion of management, all adjustments, including normal recurring accruals considered necessary for a fair presentation, have been included. Cash and Cash Equivalents—The Company considers all liquid debt instruments purchased with a maturity of three months or less to be cash equivalents. Concentration of Credit Risk—The Company maintains checking accounts for Arrowhead and separate accounts for each Subsidiary at any of three financial institutions. These accounts are insured by the Federal Deposit Insurance Corporation (FDIC) for up to $250,000 per account. The Company has two wealth management accounts at the same financial institutions that invest in higher yield money market accounts and in government securities. Management believes the Company is not exposed to significant credit risk due to the financial position of the depository institution in which these deposits are held. Property and Equipment—Property and equipment are recorded at cost. Depreciation of property and equipment is recorded using the straight-line method over the respective useful lives of the assets ranging from three to seven years. Leasehold improvements are amortized over the lesser of the expected useful life or the remaining lease term. Intellectual Property—At September 30, 2011, intellectual property consisted of patents and patent applications licensed or purchased in the gross amount of $3,349,563. The accumulated amortization of patents totaled $1,618,352 at September 30, 2011. Patents are amortized over three years to twenty years. The weighted average original amortization period is twelve years. The weighted average remaining amortization period is seven years. Amortization is expected to be $241,808 for fiscal years 2012, 2013, 2014, 2015 and 2016, and $522,174 thereafter. Long-lived assets, such as property, equipment and intangible assets subject to amortization are reviewed for impairment whenever events or circumstances indicate that the carrying amount of these assets may not be recoverable. In reviewing for impairment, we compare the carrying value of such assets to the estimated undiscounted future cash flows expected from the use of the assets and their eventual disposition. When the estimated undiscounted future cash flows are less than their carrying amount, an impairment loss is recognized equal to the difference between the assets' fair value and their carrying value. Equity Investments—Arrowhead has a non-controlling equity investment in Nanotope, a privately held biotechnology company, which is recorded in Other Assets. This investment is carried at cost less Arrowhead's proportionate share of Nanotope's operating loss for the period since investment. Arrowhead utilizes the equity method of accounting as it owns more than 20% of the voting equity and has the ability to exercise significant influence over this company. This investment is risky as the technologies and markets for Nanotope's products are still in the development stage, commercially viable products may never be developed, and markets for such products may never be significant. Arrowhead could lose its entire investment in Nanotope. Arrowhead monitors this investment for impairment and makes appropriate reductions in carrying value when necessary. Minority Equity Investments—The Company's minority equity investment in Leonardo, a privately held biotechnology company, is recorded in Other Assets. This investment is accounted for under the cost method of accounting as Arrowhead owns less than 20% of the voting equity and only has the ability to exercise nominal, not significant, influence over this company. This investment is risky as the technologies and markets for Leonardo's products are still in the development stage, commercially viable products may never be developed, and markets for such products may never be significant. Arrowhead could lose its entire investment in Leonardo. Arrowhead monitors this investment for impairment and makes appropriate reductions in carrying value when necessary. Noncontrolling Interests in Majority-Owned Subsidiaries—Operating losses applicable to majority-owned Calando, Ablaris and Unidym have periodically exceeded the noncontrolling interests in the equity capital of either Subsidiary. Such excess losses applicable to the noncontrolling interests have been and are borne by the Company as there is no obligation of the noncontrolling interests to fund any losses in excess of their original investment. There is also no obligation or commitment on the part of the Company to fund operating losses of any Subsidiary whether wholly-owned or majority-owned. The Company allocates the noncontrolling interest's share of net loss in excess of the noncontrolling interest's initial investment in accordance with FASB ASC 810-10, which was effective for the Company on October 1, 2009. When there is a change in the Company's proportionate share of a development-stage Subsidiary resulting from additional equity transactions in a Subsidiary, the change is accounted for as an equity transaction in consolidation. To the extent that the increase in the calculated value of the Company's interest in the equity of the Subsidiary exceeds the Company's investment in the offering, that increase in value is referred to as the Company's "increase in its proportionate share of the Subsidiary's equity" and the amount is recorded as an increase in the Company's Additional Paid-in Capital. Revenue Recognition—Revenue from product sales are recorded when persuasive evidence of an arrangement exists, title has passed and delivery has occurred, a price is fixed and determinable, and collection is reasonably assured. We may generate revenue from product sales, technology licenses, collaborative research and development arrangements, and research grants. Revenue under technology licenses and collaborative agreements typically consists of nonrefundable and/or guaranteed technology license fees, collaborative research funding and various milestone and future product royalty or profit-sharing payments. Revenue associated with research and development funding payments, under collaborative agreements, is recognized ratably over the relevant periods specified in the agreement, generally the research and development period. Revenue from up-front license fees and milestones and product royalties are recognized as earned based on the completion of the milestones and product sales, as defined in the respective agreements. Payments received in advance of recognition as revenue are recorded as deferred revenue. Allowance for Doubtful Accounts—The Company accrues an allowance for doubtful accounts based on estimates of uncollectible revenues by analyzing historical collections, accounts receivable aging and other factors. Accounts receivable are written off when all collection attempts have failed. Research and Development—Costs and expenses that can be clearly identified as research and development are charged to expense as incurred in accordance with FASB ASC 730-10. Earnings (Loss) per Share—Basic earnings (loss) per share is computed using the weighted-average number of common shares outstanding during the period. Diluted earnings (loss) per share are computed using the weighted-average number of common shares and dilutive potential common shares outstanding during the period. Dilutive potential common shares primarily consist of stock options issued to employees and consultants and warrants to purchase Common Stock of the Company. Stock-Based Compensation—The Company accounts for share-based compensation arrangements in accordance with FASB ASC 718, which requires the measurement and recognition of compensation expense for all share-based payment awards to be based on estimated fair values. We use the Black-Scholes option valuation model to estimate the fair value of our stock options at the date of grant. The Black-Scholes option valuation model requires the input of subjective assumptions to calculate the value of stock options. We use historical data among other information to estimate the expected price volatility and the expected forfeiture rate. Income Taxes—The Company accounts for income taxes under the liability method, which requires the recognition of deferred income tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. Under this method, deferred income taxes are recognized for the tax consequences in future years of differences between the tax bases of assets and liabilities and their financial reporting amounts at each period end based on enacted tax laws and statutory tax rates applicable to the periods in which the differences are expected to affect taxable income. Valuation allowances are established, when necessary, to reduce deferred income tax assets to the amount expected to be realized. The provision for income taxes, if any, represents the tax payable for the period and the change in deferred income tax assets and liabilities during the period. Recently Issued Accounting Standards In June 2010, the FASB issued ASU No. 2010-17, Revenue Recognition—Milestone Method (Topic 605): Milestone Method of Revenue Recognition. This ASU codifies the consensus reached in EITF Issue No. 08-9, "Milestone Method of Revenue Recognition." The amendments to the Codification provide guidance on defining a milestone and determining when it may be appropriate to apply the milestone method of revenue recognition for research or development transactions. Consideration that is contingent on achievement of a milestone in its entirety may be recognized as revenue in the period in which the milestone is achieved only if the milestone is judged to meet certain criteria to be considered substantive. Milestones should be considered substantive in their entirety and may not be bifurcated. An arrangement may contain both substantive and nonsubstantive milestones, and each milestone should be evaluated individually to determine if it is substantive. This guidance was adopted effective October 1, 2010. The adoption of this guidance did not have a material impact on our consolidated financial statements. In January 2010, the FASB issued Accounting Standards Update ASU No. 2010-06, "Fair Value Measurements and Disclosures (Topic 820) – Improving Disclosures about Fair Value Measurements". This guidance requires new disclosures related to recurring and nonrecurring fair value measurements. The guidance requires disclosure of transfers of assets and liabilities between Level 1 and Level 2 of the fair value measurement hierarchy, including the reasons and the timing of the transfers and information on purchases, sales, issuance, and settlements on a gross basis in the reconciliation of the assets and liabilities measured under Level 3 of the fair value measurement hierarchy. The adoption of this guidance is effective for interim and annual reporting periods beginning after December 15, 2009. We have adopted this guidance in the financial statements presented herein, which did not have a material impact on our consolidated financial position or results of operations. In October 2009, the FASB issued ASU 2009-13, which amends ASC Topic 605, Revenue Recognition. This new accounting guidance relates to the revenue recognition of multiple element arrangements. The new guidance states that, if vendor specific objective evidence or third party evidence for deliverables in an arrangement cannot be determined, companies will be required to develop a best estimate of the selling price for separate deliverables and allocate arrangement consideration using the relative selling price method. We adopted this guidance as of January 1, 2010 on a prospective basis. The adoption of this guidance did not have a material impact on our consolidated financial statements. In October 2009, the FASB issued authoritative guidance on multiple-deliverable revenue arrangements, ASC 605-25. This guidance amends the existing criteria for separating consideration received in multiple-deliverable arrangements and requires that arrangement consideration be allocated at the inception of the arrangement to all deliverables based on their relative selling price. The guidance establishes a hierarchy for determining the selling price of a deliverable which is based on vendor-specific objective evidence, third-party evidence, or management estimates. Expanded disclosures related to multiple-deliverable revenue arrangements are also required. This guidance is effective for the Company beginning fiscal year 2011. We have adopted this guidance in the financial statements presented herein, which did not impact our consolidated financial position or results of operations.

- Definition

The entire disclosure for the organization, consolidation and basis of presentation of financial statements disclosure, and significant accounting policies of the reporting entity. May be provided in more than one note to the financial statements, as long as users are provided with an understanding of (1) the significant judgments and assumptions made by an enterprise in determining whether it must consolidate a VIE and/or disclose information about its involvement with a VIE, (2) the nature of restrictions on a consolidated VIE's assets reported by an enterprise in its statement of financial position, including the carrying amounts of such assets, (3) the nature of, and changes in, the risks associated with an enterprise's involvement with the VIE, and (4) how an enterprise's involvement with the VIE affects the enterprise's financial position, financial performance, and cash flows. Describes procedure if disclosures are provided in more than one note to the financial statements.

+ References + Details

Investment In Subsidiaries

12 Months Ended

Sep. 30, 2011

Investment In Subsidiaries [Abstract]

Investment In Subsidiaries

NOTE 2. INVESTMENT IN SUBSIDIARIES

Calando Pharmaceuticals, Inc. (formerly known as Insert Therapeutics, Inc.)

On April 17, 2008, Calando merged with and into Insert, with Insert as the surviving company. Prior to the merger, Arrowhead invested an aggregate of $23.2 million in Calando through equity and debt financings. As a condition of the merger, the Preferred Stock of each of Calando and Insert was converted into common stock and the loans were converted to equity. As a result of the merger, shares of Insert common stock were issued to the stockholders of the former Calando, and Insert changed its name to Calando Pharmaceuticals, Inc.

On November 26, 2008, Calando entered into Unsecured Convertible Promissory Note Agreements ("Notes") for $2.5 million with accredited investors and Arrowhead, which invested $200,000 in the Notes offering. Arrowhead subsequently invested an additional $600,000 in the same offering. Subsequently, most of the Notes were converted to equity as described below. At September 30, 2011 and 2010, one Note for $500,000 remained outstanding. The Notes had a 10% interest rate and matured on November 26, 2010. The $500,000 remaining Note is convertible into Calando common stock and can be redeemed for two times their face value plus interest in the event of a sale of Calando or at maturity. To facilitate this investment in Calando, Arrowhead subordinated a series of 6% simple interest loans and advances totaling approximately $5.3 million of principal plus interest.

Effective June 23, 2009, to facilitate licensing transactions with a third party, holders (including Arrowhead) of an aggregate of $2.9 million of the Notes, including accrued but unpaid interest, converted the principal and accrued interest into newly authorized Calando Series A Preferred Stock. The non-voting Series A Preferred Stock has a liquidation preference of 2.5 times the Series A Original Issue Price of $1,000 per share and is convertible into common stock at a conversion price of $0.576647 per share. Arrowhead converted all of its Notes representing a principal balance of $800,000, plus accrued but unpaid interest, into 829 shares of Series A Preferred Stock. One third-party Note for $500,000 plus interest remains outstanding.

As of September 30, 2011, Arrowhead had a 10% simple-interest working promissory note and advances outstanding to Calando totaling $907,501, which are payable upon demand.

In fiscal 2010, Arrowhead issued 122,000 shares of its Common Stock in exchange for 3,050,000 shares of Calando common stock, with several minority stockholders of Calando. In conjunction with this exchange, Arrowhead also issued 26,400 warrants to purchase Arrowhead Common Stock in exchange for 660,000 warrants to purchase Calando common stock.

In January 2011, Arrowhead invested $9.1 million, through a cash investment of $1.0 million and the conversion of $8.1 million intercompany debt, acquiring newly issued Calando Series B and Series C preferred stock.

As of September 30, 2011, Arrowhead owned 79% of the outstanding shares of Calando and 74% on a fully diluted basis.

Ablaris Therapeutics, Inc.

Ablaris was formed and began operations in the first quarter of fiscal 2011 through the licensing of certain anti-obesity technology developed at the MD Anderson Cancer Center at the University of Texas. During the year ended September 30, 2011, Ablaris raised $2.9 million in cash, of which $1.3 million was invested by Arrowhead and $1.6 million was invested by outside investors, through the issuance of Series A Preferred stock.

As of September 30, 2011, Arrowhead owned 64% of the outstanding shares of Ablaris and 64% on a fully diluted basis.

Nanotope, Inc.

Nanotope is developing advanced nanomaterials for the treatment of spinal cord injuries, cartilage regeneration and wound healing. In April 2008, Arrowhead acquired a 5.8% ownership interest in Nanotope. In July and September 2008, Arrowhead acquired 1,801,802 shares of Series B Preferred Stock of Nanotope for two payments of $1 million each, increasing Arrowhead's ownership interest in Nanotope to approximately 23%. Since inception, Nanotope's revenue has been negligible. Operating expenses for the twelve months ended September 30, 2011 were approximately $1,161,000. Nanotope's net loss for the twelve months ended September 30, 2011 was $709,000. Arrowhead accounts for its investment in Nanotope using the equity method of accounting. As of September 30, 2011, Nanotope had indebtedness to Arrowhead in the amount of $1,213,000, included in other receivables, which is expected to be repaid or converted to equity.

Summarized financial information for Nanotope, Inc. is as follows:


	September 30, 2011			September 30, 2010
Current assets	$	21,000		$	16,000
Non-current assets		85,000			130,000
Liabilities		1,255,000			585,000
Equity		(1,149,000	)		(439,000	)

	For the year ended September 30, 2011			For the year ended September 30, 2010
Revenue	$	515,000		$	9,000
Operating expenses		1,161,000			975,000
Net Loss	$	(709,000	)	$	(955,000	)

	For the year ended September 30, 2011			For the year ended September 30, 2010
Cash flows used in operating activities	$	(705,000	)	$	(329,000	)
Cash flows used in investing activities		(31,000	)		(7,000	)
Cash flows provided by financing activities		746,000			—

Leonardo Biosystems, Inc.

Leonardo is developing a drug-delivery platform technology based on novel methods of designing spheroid porous silicon microparticles that selectively accumulate in tumor vasculature. In April 2008, Arrowhead acquired a 6.13% ownership interest in Leonardo. Arrowhead accounts for its investment in Leonardo using the cost method of accounting. As of September 30, 2011, Leonardo had indebtedness to Arrowhead in the amount of $396,000, included in other receivables, which is expected to be repaid or converted to equity. As of September 30, 2011, Arrowhead's ownership interest in Leonardo was 5%.

- Definition

The entire disclosure for equity investment, or group of investments, for which combined disclosure is appropriate, including: (a) the name of each investee and percentage of ownership of common stock, (b) accounting policies for investments in common stock, (c) difference between the amount at which the investment is carried and the amount of underlying equity in net assets and the accounting treatment of the difference, (d) the total fair value of each identified investment for which a market value is available, (e) summarized information as to assets, liabilities, and results of operations of the investees (for investments in unconsolidated subsidiaries, common stock of joint ventures, or other investments using the equity method), and (f) material effects of possible conversions, exercises, or contingent issuances of the investee. Other disclosures include (a) the names of any investee in which the investor owns 20 percent or more of the voting stock and investment is not accounted for using the equity method, and the reasons why not, and (b) the names of any investee in which the investor owns less than 20 percent of the voting stock and the investment is accounted for using the equity method, and the reasons why it is.

+ References + Details

Discontinued Operations	12 Months Ended
Discontinued Operations	Sep. 30, 2011
Discontinued Operations [Abstract]
Discontinued Operations	NOTE 3. *DISCONTINUED OPERATIONS* Unidym, Inc. Founded by Arrowhead in 2005, Unidym is developing electronic applications of carbon nanotubes. In line with the Company's strategy to focus on nanomedicine, Arrowhead sold its ownership interest in Unidym to Wisepower in January 2011. The consideration included $5.0 million in Wisepower stock and bonds, a percentage of certain revenue streams, as well as contingent payments up to $140 million based on revenue milestones over a ten-year period. In conjunction with the disposition of Unidym, the gain on the sale and the results of historical operations are recorded as discontinued operations in the Company's Statements of Operations. Additionally, the cash flows from Unidym are reflected separately as cash flows from discontinued operations. Potential future cash flows as discussed above will be reflected as a part of cash flows from discontinued operations in the Company's Consolidated Statements of Cash Flows. Tego Biosciences, Inc. On April 20, 2007, Tego, a wholly-owned subsidiary of Arrowhead, acquired the assets of C Sixty, Inc., a Texas-based company developing protective products based on the anti-oxidant properties of fullerenes. On December 23, 2009, Tego completed the sale of all of its non-cash intellectual property assets to Luna Innovations, Inc. The consideration included an upfront purchase price of $350,000 and reimbursements of patent and license expenses of $80,000, as well as contingent payments based on milestones and royalties for each fullerene product developed by Luna and covered by Tego intellectual property. Due to the sale of substantially all of Tego's assets, the operations of Tego ceased and the gain on the sale and the results of historical operations are recorded as discontinued operation in the Company's Statements of Operations. Additionally, the cash flows from Tego are reflected separately as cash flows from discontinued operations. Potential future cash flows associated with the Luna APA, as discussed above, will be reflected as a part of cash flows from discontinued operations in the Company's Consolidated Statements of Cash Flows.

- Definition

The entire disclosure for the facts and circumstances leading to the completed or expected disposal, manner and timing of disposal, the gain (loss) recognized in the income statement and the income statement caption that includes that gain (loss), amounts of revenues and pretax profit or loss reported in discontinued operations, the segment in which the disposal group was reported, and the classification (whether sold or classified as held for sale) and carrying value of the assets and liabilities comprising the disposal group. Includes all disposal groups, including those classified as components of the entity (discontinued operations).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 144
-Paragraph 43-48
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2941-110230

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-Name Accounting Standards Codification
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-Section 50
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+ Details

Notes Payable	12 Months Ended
Notes Payable	Sep. 30, 2011
Notes Payable [Abstract]
Notes Payable	NOTE 4. *NOTES PAYABLE* On November 26, 2008, Calando entered into Unsecured Convertible Promissory Note Agreements ("Notes") for $2.5 million with accredited investors and Arrowhead, which invested $200,000 in the Notes offering. Arrowhead subsequently invested an additional $600,000 in the same offering. Except for one Note in the principal amount of $500,000, all Notes and accrued interest were converted into a total of 2,950 shares of Calando Series A Preferred Stock on June 23, 2009. The remaining Note had a 10% interest rate, matured on November 26, 2010, and was renegotiated and extended until November 26, 2013. The terms of the new note include a 10% interest rate and require two times principal payment upon certain events as defined in the note and at maturity.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References + Details

Stockholders' Equity

12 Months Ended

Sep. 30, 2011

Stockholders' Equity [Abstract]

Stockholders' Equity

NOTE 5. STOCKHOLDERS' EQUITY

At September 30, 2011, the Company had a total of 150,000,000 shares of capital stock authorized for issuance, consisting of 145,000,000 shares of Common Stock, par value $0.001, and 5,000,000 shares of Preferred Stock, par value $0.001. On November 17, 2011, the Company effected a reverse stock split in the ratio of 1 for 10, all share and per share data below reflects an adjustment for the reverse stock split.

At September 30, 2011, 8,642,286 shares of Common Stock were outstanding. At September 30, 2011, 153,200 shares and 575,896 shares were reserved for issuance upon exercise of options granted under Arrowhead's 2000 Stock Option Plan and 2004 Equity Incentive Plan, respectively.

On December 11, 2009, the Company sold an aggregate of 508,343 units in a private placement transaction with accredited investors. Each unit consisted of one share of Arrowhead Common Stock and a warrant to purchase an additional share of Common Stock exercisable at $5.09 per share. The unit price was $6.34, based upon the closing bid price on the Company's Common Stock on December 11, 2009, which was $5.09, plus $1.25 for the purchase of the warrant. The warrants became exercisable on June 12, 2010 and remain exercisable until December 11, 2014. The market conditions required for redemption provided for in the warrants has been met and the warrants are eligible for redemption by the Company. Gross proceeds of the offering were approximately $3.2 million.

On June 17, 2010, the Company sold an aggregate of 659,298 units at a price of $13.12 per unit in a registered offering to institutional and accredited investors. Each unit consisted of one share of Arrowhead Common Stock and a warrant to purchase 0.5 share of Common Stock exercisable at $16.50 per share. The warrants contain an antidilution provision which can result in an adjustment to the exercise price under certain circumstances, and the current exercise price is $3.70. Gross proceeds from the offering were $8.65 million before deducting placement agent commission and other offering expenses of approximately $800,000.

On September 30, 2011, the Company sold 1,458,917 shares of Common Stock at a price of $3.80 per share. Cash proceeds received in fiscal 2011 were $4.6 million, $0.9 million are expected to be received in fiscal 2012, and $0.2 million related to a reduction in professional fees.

The following table summarizes information about warrants outstanding at September 30, 2011:


Exercise prices	Number of Warrants	Remaining Life in Years
$70.60	94,896	5.6
$20.00	386,399	1.9
$5.00	1,163,033	3.2
$5.10	461,024	3.2
$3.80	329,649	4.2

Total warrants outstanding	2,435,001

- Definition

The entire disclosure for shareholders' equity, comprised of portions attributable to the parent entity and noncontrolling interest, if any, including other comprehensive income (as applicable). Including, but not limited to: (1) balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings; (2) accumulated balance for each classification of other comprehensive income and total amount of comprehensive income; (3) amount and nature of changes in separate accounts, including the number of shares authorized and outstanding, number of shares issued upon exercise and conversion, and for other comprehensive income, the adjustments for reclassifications to net income; (4) rights and privileges of each class of stock authorized; (5) basis of treasury stock, if other than cost, and amounts paid and accounting treatment for treasury stock purchased significantly in excess of market; (6) dividends paid or payable per share and in the aggregate for each class of stock for each period presented; (7) dividend restrictions and accumulated preferred dividends in arrears (in aggregate and per share amount); (8) retained earnings appropriations or restrictions, such as dividend restrictions; (9) impact of change in accounting principle, initial adoption of new accounting principle and correction of an error in previously issued financial statements; (10) shares held in trust for Employee Stock Ownership Plan (ESOP); (11) deferred compensation related to issuance of capital stock; (12) note received for issuance of stock; (13) unamortized discount on shares; (14) description, terms, and number of warrants or rights outstanding; (15) shares under subscription and subscription receivables, effective date of new retained earnings after quasi-reorganization and deficit eliminated by quasi-reorganization and, for a period of at least ten years after the effective date, the point in time from which the new retained dates; and (16) retroactive effective of subsequent change in capital structure.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 10
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 4
-Section 08
-Paragraph d

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 1
-Section B
-Paragraph 7, 11A
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 129
-Paragraph 2, 3, 4, 5, 6, 7, 8
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
-Number 210
-Section 08
-Article 4

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30, 31
-Article 5

Reference 9: http://www.xbrl.org/2003/role/presentationRef
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-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section E

Reference 10: http://www.xbrl.org/2003/role/presentationRef
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-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section C

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-URI http://asc.fasb.org/extlink&oid=6521494

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+ Details

Leases	12 Months Ended
Leases	Sep. 30, 2011
Leases [Abstract]
Leases	NOTE 6. *LEASES* In April 2011, the Company's corporate headquarters lease expired, and the Company did not exercise its renewal option. The company is currently leasing temporary offices. The temporary offices are expected to be utilized for several months at a rental rate of approximately $8,000 per month. The current rental agreement is on a month-to-month basis and there were no long-term commitments at September 30, 2011. On October 21, 2011, Arrowhead acquired the RNAi operations from Roche, including its research facility in Madison, Wisconsin. Its lease expires on February 28, 2019; monthly rental expense is approximately $56,500. Facility and equipment rent expense for the year ended September 30, 2011 and 2010 was $161,759 and $268,330, respectively. From inception to date, rent expense was $3,645,381. Rent expense related to Unidym, until its disposal in January 2011, is included as a part of income/loss from discontinued operations.

- Definition

The entire disclosure for lessee entity's leasing arrangements including, but not limited to, all of the following: (a.) The basis on which contingent rental payments are determined, (b.) The existence and terms of renewal or purchase options and escalation clauses, (c.) Restrictions imposed by lease agreements, such as those concerning dividends, additional debt, and further leasing.

+ References + Details

Stock-Based Compensation

12 Months Ended

Sep. 30, 2011

Stock-Based Compensation [Abstract]

Stock-Based Compensation

NOTE 7. STOCK-BASED COMPENSATION

Arrowhead has two plans that provide for equity-based compensation. Under the 2000 Stock Option Plan, 153,200 shares of Arrowhead's Common Stock are reserved for issuance upon exercise of non-qualified stock options. No further grants can be made under the 2000 Stock Option Plan. The 2004 Equity Incentive Plan reserves 970,443 shares for the grant of stock options, stock appreciation rights, restricted stock awards and performance unit/share awards by the Board of Directors to employees, consultants and others. As of September 30, 2011, there were options granted and outstanding to purchase 153,200 and 575,896 shares of Common Stock under the 2000 Stock Option Plan and the 2004 Equity Incentive Plan, respectively. During the year ended September 30, 2011, 20,000 options were granted under the 2004 Equity Incentive Plan. All share and per share data in this footnote has been adjusted to reflect the 1 for 10 reverse stock split effected on November 17, 2011.

The following tables summarize information about stock options:


	Number of Options Outstanding			Weighted- Average Exercise Price Per Share		Weighted- Average Remaining Contractual Term		Aggregate Intrinsic Value
Balance At September 30, 2009		290,158		$	17.35
Granted		525,175			6.88
Cancelled		(2,312	)		11.10
Exercised		(687	)		11.10

Balance At September 30, 2010		812,334			10.62
Granted		20,000			5.86
Cancelled		(100,539	)		21.32
Exercised		(2,699	)		5.10

Balance At September 30, 2011		729,096		$	9.03		7.0 years	$	—

Exercisable At September, 30, 2011		570,307		$	9.39		6.6 years	$	—

Stock-based compensation expense for the years ended September 30, 2011 and 2010 was $1,404,430 and $1,582,149, respectively. For the year ended September 30, 2011 and 2010, $27,519 and $157,856, respectively, of this expense is included in discontinued operations, and the balance is included in Salary expense in the Company's consolidated statements of operations. There is no income tax benefit as the company is currently operating at a loss and an actual income tax benefit may not be realized. The result of the loss creates a timing difference, resulting in a deferred tax asset, which is fully reserved by a valuation allowance.

The fair value of the options granted by Arrowhead for the years ended September 30, 2011 and 2010 is estimated at $93,004 and $2,939,928, respectively. The aggregate fair value of options granted by Calando for the years ended September 30, 2011 is estimated at $33,870. No Calando options were issued during the year ended September 30, 2010. The intrinsic value of the options exercised during fiscal 2011 and 2010 was $3,666 and $6,875, respectively.

As of September 30, 2011, the pre-tax compensation expense for all unvested stock options at Arrowhead in the amount of approximately $1,091,513 will be recognized in our results of operations over a weighted average period of 2.4 years. As of September 30, 2011, the pre-tax compensation expense for all unvested stock options at Calando in the amount of approximately $69,183 will be recognized in our results of operations over a weighted average period of 2.8 years.

The fair value of each stock option award is estimated on the date of grant using the Black-Scholes option pricing model. The Black-Scholes option valuation model was developed for use in estimating the fair value of traded options, which do not have vesting restrictions and are fully transferable. The determination of the fair value of each stock option is affected by our stock price on the date of grant, as well as assumptions regarding a number of highly complex and subjective variables. Because the Company's employee stock options have characteristics significantly different from those of traded options, and because changes in the subjective input assumptions can materially affect the fair value estimate, in management's opinion, the existing models do not necessarily provide a reliable single measure of the fair value of its employee stock options. The assumptions used to value stock options are as follows:


	Year Ended September 30,
	2011		2010
Dividend yield		—		—
Risk-free interest rate		1.11% to 2.90%		2.00% to 3.42%
Volatility		100%		100%
Expected life (in years)		5.5 to 6.25		5 to 6.25
Weighted average grant date fair value per share of options granted		$4.70		$5.60

The dividend yield is zero as the Company currently does not pay a dividend.

The risk-free interest rate is based on the U.S. Treasury bond.

Volatility is estimated based on volatility average of the Company's Common Stock price.

- Definition

Tabular disclosure of components of a stock option or other award plan under which equity-based compensation is awarded to employees, typically comprised of the amount of unearned compensation (deferred compensation cost), compensation expense, and changes in the quantity and fair value of the shares (or other type of equity) granted, exercised, forfeited, and issued and outstanding pertaining to that plan. Disclosure may also include nature and general terms of such arrangements that existed during the period and potential effects of those arrangements on shareholders, effect of compensation cost arising from equity-based payment arrangements on the income statement, method of estimating the fair value of the goods or services received, or the fair value of the equity instruments granted, during the period, cash flow effects resulting from equity-based payment arrangements and, for registrants that accelerate vesting of out of the money share options, reasons for the decision to accelerate.

+ References + Details

Fair Value Measurements & Derivative Instruments

12 Months Ended

Sep. 30, 2011

Fair Value Measurements & Derivative Instruments [Abstract]

Fair Value Measurements & Derivative Instruments

NOTE 8. FAIR VALUE MEASUREMENTS & DERIVATIVE INSTRUMENTS

The Company measures its financial assets and liabilities at fair value. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (i.e., exit price) in an orderly transaction between market participants at the measurement date. Additionally, the Company is required to provide disclosure and categorize assets and liabilities measured at fair value into one of three different levels depending on the assumptions (i.e., inputs) used in the valuation. Level 1 provides the most reliable measure of fair value while Level 3 generally requires significant management judgment. Financial assets and liabilities are classified in their entirety based on the lowest level of input significant to the fair value measurement. The fair value hierarchy is defined as follows:

Level 1—Valuations are based on unadjusted quoted prices in active markets for identical assets or liabilities.

Level 2—Valuations are based on quoted prices for similar assets or liabilities in active markets, or quoted prices in markets that are not active for which significant inputs are observable, either directly or indirectly.

Level 3—Valuations are based on prices or valuation techniques that require inputs that are both unobservable and significant to the overall fair value measurement. Inputs reflect management's best estimate of what market participants would use in valuing the asset or liability at the measurement date.

The following table summarizes fair value measurements at September 30, 2010 and September 30, 2011 for assets and liabilities measured at fair value on a recurring basis:

September 30, 2010:

		$2,408,522		$2,408,522		$2,408,522		$2,408,522
	Level I		Level II		Level III		Total
Cash and cash equivalents	$	6,847,162	$	—	$	—	$	6,847,162
Derivative liabilities	$	—	$	—	$	2,408,522	$	2,408,522
September 30, 2011:
	Level I		Level II		Level III		Total
Cash and cash equivalents	$	7,507,389	$	—	$	—	$	7,507,389
Marketable securities	$	634,585	$	—	$	—	$	634,585
Derivative assets	$	—	$	—	$	161,125	$	161,125
Derivative liabilities	$	—	$	—	$	944,980	$	944,980

As part of the sale of Unidym in January 2011, Arrowhead received common stock in Wisepower, originally valued at $2.5 million, $100,000 of which is due to a third party. Arrowhead has the ability to sell the shares of stock in Wisepower, subject to certain limits on volume of sales over a nine-month period ending in October 2011. During the year ended September 30, 2011, Arrowhead sold approximately 60% of the original holdings; the remaining shares had a market value of $0.6 million at September 30, 2011, and were sold for $0.5 million in October 2011. The recorded value of the stock is adjusted to fair market value based on quotations from the KOSDAQ, a Korean stock exchange, and published foreign exchange rates. Marketable securities are included as part of other current assets in the Company's consolidated balance sheet.

As part of the sale of Unidym in January 2011, Arrowhead received a bond from Wisepower in the face amount of $2.5 million. The bond is convertible to Wisepower common stock beginning on January 17, 2012 at a price of $2.00 per share. The conversion feature is subject to derivative accounting as prescribed under ASC 815. Accordingly, the fair value of the conversion feature on the date of issuance was estimated using an option pricing model and recorded on the Company's consolidated balance sheet as a derivative asset. The fair value of the conversion feature is estimated at the end of each reporting period and the change in the fair value of the conversion feature is recorded as a nonoperating gain/loss as change in value of derivatives in Company's consolidated statement of operations. A portion of the bond is owed to a third party, as such the company records a derivative asset for the entire conversion feature and records a derivative liability for the portion related to the third party. The original fair value of the derivative relating to the third party was $26,310; the fair value at September 30, 2011 was $6,854. The loss from the change in value of the derivative asset, net of the derivative liability of $437,919 is reflected in the change in value of derivatives in the Company's consolidated statement of operations.

During the year ended September 30, 2011, the Company recorded a loss from the change in fair value of the derivative asset, net of $437,919. The assumptions used in valuing the derivative asset as of September 30, 2011 were as follows:


Risk free interest rate	0.4	%
Expected life	2.3 Years
Dividend yield	none
Volatility	72	%

The following is a reconciliation of the derivative asset for the year ended September 30, 2011:


Value at October 1, 2010	$	—
Receipt of instruments		618,500
Decrease in value		(457,375	)
Net settlements		—

Value at September 30, 2011	$	161,125

As part of the equity financing on June 17, 2010, as described in Note 5, Arrowhead issued warrants to acquire up to 329,649 shares of Common Stock (the "Warrants") which contain anti-dilution protection. Under the certain provisions of the Warrants, if, during the term of the Warrants, the Company issues Common Stock at a price lower than the exercise price of the Warrants, the exercise price of the Warrants would be reduced to the amount equal to the issuance price of the Common Stock. Because the Warrants have this feature, the Warrants are subject to derivative accounting as prescribed under ASC 815. Accordingly, the fair value of the Warrants on the date of issuance was estimated using an option pricing model and recorded on the Company's consolidated balance sheet as a derivative liability. The fair value of the Warrants is estimated at the end of each reporting period and the change in the fair value of the Warrants is recorded as a nonoperating gain or loss in the Company's consolidated statement of operations. During the year ended September 30, 2011, the Company recorded a gain from the change in fair value of the derivative liability of $1,501,289. The assumptions used in valuing the derivative liability as of September 30, 2011 were as follows:


Risk free interest rate	0.9	%
Expected life	4.2 Years
Dividend yield	none
Volatility	100	%

The following is a reconciliation of the derivative liability related to these warrants for through September 30, 2011:


Value at October 1, 2009	$	—
Receipt of instruments		4,169,907
Decrease in value		(1,761,385	)
Net settlements		—

Value at October 1, 2010	$	2,408,522
Receipt of instruments		—
Decrease in value		(1,501,289	)
Net settlements		—

Value at September 30, 2011	$	907,233

In conjunction with the financing of Ablaris during the year ended September 30, 2011, Arrowhead sold exchange rights to certain investors whereby the investors have the right to exchange their shares of Ablaris for a prescribed number of Arrowhead shares based upon a predefined ratio. The exchange rights have a seven-year term. During the first year, the exchange right allows the holder to exchange one Ablaris share for 0.6 Arrowhead shares. This ratio declines to 0.4 in the second year, 0.3 in the third year and 0.2 in the fourth year. In the fifth year and beyond the exchange ratio is 0.1. Exchange rights for 675,000 Ablaris shares were sold during the year ended September 30, 2011, and remain outstanding at September 30, 2011. The exchange rights are subject to derivative accounting as prescribed under ASC 815. Accordingly, the fair value of the exchange rights on the date of issuance was estimated using an option pricing model and recorded on the Company's consolidated balance sheet as a derivative liability. The fair value of the exchange rights is estimated at the end of each reporting period and the change in the fair value of the exchange rights is recorded as a nonoperating gain or loss in the Company's consolidated statement of operations. During the year ended September 30, 2011, the Company recorded a gain from the change in fair value of the derivative liability of $69,758. The assumptions used in valuing the derivative liability as of September 30, 2011 were as follows:


Risk free interest rate	1.3	%
Expected life	6.3 Years
Dividend yield	none
Volatility	100	%

The following is a reconciliation of the derivative liability related to these exchange rights for the year ended September 30, 2011:


Value at October 1, 2010	$	—
Issuance of instruments		100,650
Change in value		(69,758	)
Net settlements		—

Value at September 30, 2011	$	30,892

The carrying amounts of the Company's other financial instruments, which include accounts receivable, accounts payable, and accrued expenses approximate their respective fair values due to the relatively short-term nature of these instruments.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44A, 44B
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15C, 15D
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15A
-Subparagraph a-d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15B
-Subparagraph a, b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 3, 10, 14, 15
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32, 33, 34
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 17-22, 27, 28
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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-Name Accounting Standards Codification
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Reference 11: http://www.xbrl.org/2003/role/presentationRef
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Reference 12: http://www.xbrl.org/2003/role/presentationRef
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Reference 13: http://www.xbrl.org/2003/role/presentationRef
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+ Details

Income Taxes	12 Months Ended
Income Taxes	Sep. 30, 2011
Income Taxes [Abstract]
Income Taxes	NOTE 9. *INCOME TAXES* The Company utilizes the guidance issued by the FASB for accounting for income taxes which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. Under this method, deferred income taxes are recognized for the tax consequences in future years of differences between the tax bases of assets and liabilities and their financial reporting amounts at each year-end based on enacted tax laws and statutory tax rates applicable to the periods in which the differences are expected to affect taxable income. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount expected to be realized. The provision for income taxes represents the tax payable for the period and the change during the period in deferred tax assets and liabilities. For the years ended September 30, 2011 and 2010, the Company had consolidated net book losses of $3.5 million and $7.0 million, respectively. The losses result in a deferred income tax benefit which is offset by a deferred tax provision for the valuation allowance for a net deferred provision of zero. Since the Company is a development stage company, management has provided a 100% valuation allowance against its deferred tax assets until such time as management believes that its projections of future profits as well as expected future tax rates make the realization of these deferred tax assets more-likely-than-not. Significant judgment is required in the evaluation of deferred tax benefits and differences in future results from our estimates could result in material differences in the realization of these assets. As of September 30, 2011, the Company has available gross federal net operating loss (NOL) carry forwards of $65.3 million and gross state NOL carry forwards of $52.1 million which expire at various dates through 2029. As of September 30, 2011, the deferred tax assets were $25.2 million. The Company has recorded a full valuation allowance of $25.2 million related to federal and state net operating loss carry forwards. The Company has performed an assessment of positive and negative evidence regarding the realization of the net deferred tax asset in accordance with ASC 740-10, "Accounting for Income Taxes." This assessment included the evaluation of scheduled reversals of deferred tax liabilities, the availability of carry forwards and estimates of projected future taxable income. The Company has adopted guidance issued by the FASB that clarifies the accounting for uncertainty in income taxes recognized in an enterprise's financial statements and prescribes a recognition threshold of more likely than not and a measurement process for financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. In making this assessment, a company must determine whether it is more likely than not that a tax position will be sustained upon examination, based solely on the technical merits of the position and must assume that the tax position will be examined by taxing authorities. Our policy is to include interest and penalties related to unrecognized tax benefits in income tax expense. Interest and penalties totaled $0 for the years ended September 30, 2011 and 2010, respectively, and $0 for the period from May 7, 2003 (date of inception) through September 30, 2011. The Company files income tax returns with the Internal Revenue Service ("IRS"), the state of California and certain other taxing jurisdictions. For jurisdictions in which tax filings are prepared, the Company is no longer subject to income tax examinations by state tax authorities for years through fiscal 2006, and by the IRS

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 136, 172
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 43, 44, 45, 46, 47, 48, 49
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h))
-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 740
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Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319

+ Details

Related Party Transactions	12 Months Ended
Related Party Transactions	Sep. 30, 2011
Related Party Transactions [Abstract]
Related Party Transactions	NOTE 10. *RELATED PARTY TRANSACTIONS* Dr. Anzalone owns 1,395,900 shares of Nanotope, Inc. common stock or approximately 14.2% of Nanotope's outstanding voting securities. Dr. Anzalone does not hold options, warrants or any other rights to acquire securities of Nanotope. Dr. Anzalone has the right to appoint a representative to the board of directors of Nanotope. Dr. Anzalone currently serves on the Nanotope board in a seat reserved for Nanotope's CEO, and another individual holds the seat designated by Dr. Anzalone. Dr. Anzalone has served as President and Chief Executive Officer of Nanotope since its formation and continues to serve in these capacities. Dr. Anzalone has not received any compensation for his work on behalf of Nanotope since joining the Company on December 1, 2007. Dr. Anzalone has also waived his right to any unpaid compensation accrued for work done on behalf of Nanotope before he joined the Company. Dr. Anzalone did not participate on behalf of the Company in the negotiations of the terms of the Nanotope Series B Preferred Stock issued to the Company and did not negotiate on behalf of Nanotope after becoming the Chief Executive Officer and President of the Company. Dr. Anzalone did respond to questions asked of him by the Company's Board of Directors and management regarding Nanotope's business plan, operations and the terms of the Series B Stock Purchase Agreement and ancillary agreements. During fiscal 2009, Calando raised $2.5 million through the sale of senior unsecured convertible promissory notes ("New Notes"), to accredited investors, plus $800,000 from Arrowhead. Dr. Anzalone, Arrowhead's President and CEO, personally participated in the offering by buying $100,000 of the New Notes. As part of the private placement on December 11, 2009 (see Note 6. Stockholder's Equity), Dr. Anzalone, Arrowhead's President and CEO, personally invested $100,000. In August 2010, the Company retained Mr. Vincent Anzalone, the brother of Arrowhead's Chief Executive Officer, as a consultant for the Company, focusing on business development and market analysis, with a monthly remuneration of $10,000 per month. Mr. Vincent Anzalone was paid $20,000 during the fiscal year ended September 30, 2010, and $120,000 during the fiscal year ended September 30, 2011.

- Definition

The entire disclosure for related party transactions, including the nature of the relationship(s), a description of the transactions, the amount of the transactions, the effects of any change in the method of establishing the terms of the transaction from the previous period, stated interest rate, expiration date, terms and manner of settlement per the agreement with the related party, and amounts due to or from related parties. If the entity and one or more other entities are under common ownership or management control and this control affects the operating results or financial position, disclosure includes the nature of the control relationship even if there are no transactions between the entities. Disclosure may also include the aggregate amount of current and deferred tax expense for each statement of earnings presented where the entity is a member of a group that files a consolidated tax return, the amount of any tax related balances due to or from affiliates as of the date of each statement of financial position presented, the principal provisions of the method by which the consolidated amount of current and deferred tax expense is allocated to the members of the group and the nature and effect of any changes in that method. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 4
-Section 08
-Paragraph k

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 3A
-Section 04
-Paragraph b

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 57
-Paragraph 1-4
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k))
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+ Details

Employee Benefit Plans	12 Months Ended
Employee Benefit Plans	Sep. 30, 2011
Employee Benefit Plans [Abstract]
Employee Benefit Plans	NOTE 11. *EMPLOYEE BENEFIT PLANS* In January 2005, the Company began sponsoring a defined contribution 401(k) retirement savings plan covering substantially all of its employees. The Plan was administered under the "safe harbor" provision of ERISA. Under the terms of the plan, an eligible employee may elect to contribute a portion of their salary on a pre-tax basis, subject to federal statutory limitations. The plan allowed for a discretionary match in an amount up to 100% of each participant's first 3% of compensation contributed plus 50% of each participant's next 2% of compensation contributed. For the years ended September 30, 2011 and 2010, we recorded expenses under these plans of approximately $43,000 and $9,000, respectively and $448,000 since inception of the Company. In addition to the employee benefit plans described above, the Company participates in certain customary employee benefits plans, including those which provide health and life insurance benefits to employees.

Subsequent Events	12 Months Ended
Subsequent Events	Sep. 30, 2011
Subsequent Events [Abstract]
Subsequent Events	NOTE 12. *SUBSEQUENT EVENTS* On October 21, 2011, the Company entered into a Stock and Asset Purchase Agreement (the "RNAi Purchase Agreement") with Hoffmann-La Roche Inc. and F Hoffmann-La Roche Ltd (collectively, "Roche"), pursuant to which the Company purchased from Roche (i) all of the outstanding common stock of Roche Madison Inc. ("Roche Madison") and (ii) the intellectual property rights currently held by Roche related to its RNAi business and identified in the RNAi Purchase Agreement (the "Transaction"). In consideration for the purchase of Roche Madison and the Roche RNAi assets, the Company issued to Roche a promissory note with a principal value of $50,000 and 901,702 shares of Common Stock (as adjusted for a subsequent reverse split). Additionally, the Company agreed that, subject to stockholder approval under the NASDAQ Marketplace Rules, the Company would issue an additional 146,562 (as adjusted for a subsequent reverse split) shares of Common Stock, plus a number of additional shares equal to 9.9% of the shares of Common Stock (or common stock equivalents) sold by the Company in capital raising transactions within one year from the closing, but only with respect to the first $3,118,615 of gross offering proceeds (the "Top-up Shares"). If the Company is prohibited from issuing the Top-up Shares due to NASDAQ Marketplace Rules, then the Company must instead pay the cash value of the Top-up Shares, based on the then-current fair value of such shares. Pursuant to the RNAi Purchase Agreement, Roche has a right of first negotiation on certain product candidates developed by the Company and its affiliates relating to the purchased assets. If the Company proposes to out-license, or enters into substantive negotiations to out-license, any Clinical Candidate or Existing Candidate (as such terms are defined in the RNAi Purchase Agreement), the Company must give detailed notice of the Candidate it proposes to out-license and negotiate exclusively and in good faith with Roche for a period of time regarding the applicable out-license. This right of first negotiation applies to all Existing Candidates and the first five Clinical Candidates for which the Company delivers notice to Roche and subsequently enters into an out-license. In addition to the consideration paid by the Company at the closing of the Transaction, the Company is obligated to make certain royalty and milestone payments to Roche upon the occurrence of certain events. For certain product candidates that are developed by the Company or its affiliates and that are covered by a valid claim by the patent rights transferred in the Transaction for which the Company and Roche do not enter into a licensing arrangement, the Company will be obligated to pay a 3% royalty on Net Sales (as defined in the RNAi Purchase Agreement), provided that the royalty rate may be reduced or offset in certain circumstances. The obligation to pay royalties on such candidates will last until the later of (i) the expiration of the last to expire patent right related to such product candidate that was transferred in the Transaction and (ii) ten years after the first commercial sale of such product candidate. The Company will also be obligated to make cash payments to Roche upon the achievement of various milestones, including the first regulatory approval of an Existing Candidate in certain jurisdictions and upon certain annual sales milestones for Existing Candidates that may receive regulatory approval. The potential payments range from $2,500,000 to $6,000,000 per milestone. On October 4, 2011, the Company completed a second closing to the private placement stock issuance of September 30, 2011. On October 4, 2011, the Company sold 138,157 shares of Common Stock at a price of $3.80 per share. Cash proceeds were $525,000. On October 20, 2011, the Company and Lincoln Park Capital Fund, LLC, an Illinois limited liability company ("LPC") entered into a $15 million purchase agreement (the "Purchase Agreement"), together with a registration rights agreement, whereby LPC agreed to purchase up to $15 million of Common Stock, subject to certain limitations, from time to time during the three-year term of the Purchase Agreement. Additionally, the Company agreed to file a registration statement with the U.S. Securities & Exchange Commission covering the resale of the shares that may be issued to LPC under the Purchase Agreement. After the SEC declares effective the registration statement related to the resale of such shares, the Company will have the right, in its sole discretion, over a 36-month period to sell up to $15 million of Common Stock (subject to certain limitations) to LPC, depending on certain conditions as set forth in the Purchase Agreement. On October 21, 2011 and October 24, 2011, the Company entered into Subscription Agreements with certain accredited investors (the "Series A Purchasers"), pursuant to which the Company agreed to issue and sell an aggregate of 1,015 shares of Series A Preferred Convertible Stock, $0.001 par value per share, at a purchase price of $1,000 per share. The aggregate purchase price to be paid by the Series A Purchasers for the shares of Series A Preferred is $1,015,000. The closing of the sale of the shares occurred on October 26, 2011. On October 21, 2011, the Company entered into a Subscription Agreement with a single accredited investor, pursuant to which the Company agreed to issue and sell an aggregate of 675,000 shares of Common Stock, $0.001 par value per share, at a purchase price of $3.70 per share. The aggregate purchase price to be paid by the purchaser for the shares of Common Stock was $2,497,500. The closing of the sale of the Common Shares is expected to occur in fiscal 2012. As of November 17, 2011, the Company effected a 1 for 10 reverse stock split. As a result of the reverse stock split, each ten shares of the Company's Common Stock issued and outstanding immediately prior to the reverse split was combined into one share of Common Stock. Also, as a result of the Reverse Stock Split, the per share exercise price of, and the number of shares of Common Stock underlying Company stock options, warrants, Series A Preferred and any Common Stock based equity grants outstanding immediately prior to the reverse stock split was proportionally adjusted, based on the one-for-ten split ratio, in accordance with the terms of such options, warrants or other Common Stock based equity grants as the case may be. No fractional shares of Common Stock were issued in connection with the reverse split. Stockholders received a cash payment in lieu of any fractional shares. Unless otherwise noted, all share and per share amounts in these financial statements have been retrospectively adjusted to reflect the reverse stock split.

Label	Element	Value
Subscriptions Receivable [Member]
NET LOSS	us-gaap_ProfitLoss
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
Noncontrolling Interest [Member]
NET LOSS	us-gaap_ProfitLoss
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
Retained Earnings [Member]
NET LOSS	us-gaap_ProfitLoss	(95,238)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	(95,238)
Common Stock [Member]
NET LOSS	us-gaap_ProfitLoss
Shares, issued	us-gaap_SharesIssued	468,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	$ 4,680
Additional Paid In Capital [Member]
NET LOSS	us-gaap_ProfitLoss
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1,510,320
Issued For Cash At Zero Point Zero One Dollars Per Unit [Member]
Stock issued during period, value, new issues	us-gaap_StockIssuedDuringPeriodValueNewIssues	3,000
Issued For Cash At Zero Point Zero One Dollars Per Unit [Member] \| Subscriptions Receivable [Member]
Stock issued during period, value, new issues	us-gaap_StockIssuedDuringPeriodValueNewIssues
Issued For Cash At Zero Point Zero One Dollars Per Unit [Member] \| Noncontrolling Interest [Member]
Stock issued during period, value, new issues	us-gaap_StockIssuedDuringPeriodValueNewIssues
Issued For Cash At Zero Point Zero One Dollars Per Unit [Member] \| Retained Earnings [Member]
Stock issued during period, value, new issues	us-gaap_StockIssuedDuringPeriodValueNewIssues
Issued For Cash At Zero Point Zero One Dollars Per Unit [Member] \| Common Stock [Member]
Stock issued during period, value, new issues	us-gaap_StockIssuedDuringPeriodValueNewIssues	$ 3,000
Stock issued during period, shares, new issues	us-gaap_StockIssuedDuringPeriodSharesNewIssues	300,000
Issued For Cash At Zero Point Zero One Dollars Per Unit [Member] \| Additional Paid In Capital [Member]
Stock issued during period, value, new issues	us-gaap_StockIssuedDuringPeriodValueNewIssues
Issued For Cash At Ten Dollar Per Unit [Member]
Stock issued during period, value, new issues	us-gaap_StockIssuedDuringPeriodValueNewIssues	1,680,000
Issued For Cash At Ten Dollar Per Unit [Member] \| Subscriptions Receivable [Member]
Stock issued during period, value, new issues	us-gaap_StockIssuedDuringPeriodValueNewIssues
Issued For Cash At Ten Dollar Per Unit [Member] \| Noncontrolling Interest [Member]
Stock issued during period, value, new issues	us-gaap_StockIssuedDuringPeriodValueNewIssues
Issued For Cash At Ten Dollar Per Unit [Member] \| Retained Earnings [Member]
Stock issued during period, value, new issues	us-gaap_StockIssuedDuringPeriodValueNewIssues
Issued For Cash At Ten Dollar Per Unit [Member] \| Common Stock [Member]
Stock issued during period, value, new issues	us-gaap_StockIssuedDuringPeriodValueNewIssues	$ 1,680
Stock issued during period, shares, new issues	us-gaap_StockIssuedDuringPeriodSharesNewIssues	168,000
Issued For Cash At Ten Dollar Per Unit [Member] \| Additional Paid In Capital [Member]
Stock issued during period, value, new issues	us-gaap_StockIssuedDuringPeriodValueNewIssues	$ 1,678,320
Stock Issuance Cost Charged To Additional Paid In Capital [Member]
Stock issuance cost charged to additional paid-in capital	us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts	(168,000)
Stock Issuance Cost Charged To Additional Paid In Capital [Member] \| Subscriptions Receivable [Member]
Stock issuance cost charged to additional paid-in capital	us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts
Stock Issuance Cost Charged To Additional Paid In Capital [Member] \| Noncontrolling Interest [Member]
Stock issuance cost charged to additional paid-in capital	us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts
Stock Issuance Cost Charged To Additional Paid In Capital [Member] \| Retained Earnings [Member]
Stock issuance cost charged to additional paid-in capital	us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts
Stock Issuance Cost Charged To Additional Paid In Capital [Member] \| Common Stock [Member]
Stock issuance cost charged to additional paid-in capital	us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts
Stock Issuance Cost Charged To Additional Paid In Capital [Member] \| Additional Paid In Capital [Member]
Stock issuance cost charged to additional paid-in capital	us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts	$ (168,000)