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Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Mar. 31, 2013	May 10, 2013
Entity Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2013
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q2
Trading Symbol	ENTA
Entity Registrant Name	ENANTA PHARMACEUTICALS INC
Entity Central Index Key	0001177648
Current Fiscal Year End Date	--09-30
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		17,818,796

Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2013	Sep. 30, 2012
Current assets:
Cash and cash equivalents	$ 74,464	$ 10,511
Short-term marketable securities	34,647	33,251
Accounts receivable	669	1,049
Unbilled receivables	768	1,893
Prepaid expenses and other current assets	1,116	604
Total current assets	111,664	47,308
Property and equipment, net	876	611
Long-term marketable securities	12,629	1,656
Restricted cash	436	436
Other assets	22	2,151
Total assets	125,627	52,162
Current liabilities:
Accounts payable	2,371	1,851
Accrued expenses	2,465	3,866
Deferred revenue	115	17
Total current liabilities	4,951	5,734
Warrant liability	1,767	2,001
Other long-term liabilities	534	498
Total liabilities	7,252	8,233
Commitments and contingencies (Note 10)
Stockholders' equity (deficit):
Common stock; $0.01 par value; 100,000,000 and 70,000,000 shares authorized at March 31, 2013 and September 2012, respectively; 18,027,612 and 1,343,147 shares issued and 17,818,796 and 1,134,331 shares outstanding at March 31, 2013 and September 30, 2012, respectively	180	13
Additional paid-in capital	217,073
Treasury stock, at par value; 208,816 shares at March 31, 2013 and September 30, 2012, respectively	(2)	(2)
Accumulated other comprehensive income (loss)	(7)	10
Accumulated deficit	(98,869)	(115,374)
Total stockholders' equity (deficit)	118,375	(115,353)
Total liabilities, redeemable and convertible preferred stock and stockholders' equity (deficit)	$ 125,627	52,162
Series C, D, E, F and G Redeemable Convertible Preferred Stock
Current liabilities:
Preferred stock, value		158,955
Series A and B Convertible Preferred Shares
Current liabilities:
Preferred stock, value		$ 327

Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2013	Sep. 30, 2012
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	70,000,000
Common stock, shares issued	18,027,612	1,343,147
Common stock, shares outstanding	17,818,796	1,134,331
Treasury stock, shares	208,816	208,816
Series C, D, E, F and G Redeemable Convertible Preferred Stock
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized		45,421,288
Preferred stock, shares issued		43,115,343
Preferred stock, shares outstanding		43,115,343
Series A and B Convertible Preferred Shares
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized		566,450
Preferred stock, shares issued		566,450
Preferred stock, shares outstanding		566,450

Statements of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Statements of Operations - USD ($) $ in Thousands	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Revenue	$ 1,196	$ 36,565	$ 29,055	$ 37,306
Operating expenses:
Research and development	3,704	3,263	8,502	5,935
General and administrative	1,493	1,207	2,645	2,458
Total operating expenses	5,197	4,470	11,147	8,393
Income (loss) from operations	(4,001)	32,095	17,908	28,913
Other income (expense):
Interest income	47	15	82	29
Interest expense	(9)		(16)
Change in fair value of warrant liability	214	1	234	10
Total other income, net	252	16	300	39
Net income (loss)	(3,749)	32,111	18,208	28,952
Accretion of redeemable convertible preferred stock to redemption value	(1,244)	(1,331)	(2,526)	(2,705)
Net income attributable to participating securities		(28,152)	(13,670)	(24,071)
Net income (loss) attributable to common stockholders	$ (4,993)	$ 2,628	$ 2,012	$ 2,176
Net income (loss) per share attributable to common stockholders :
Basic	$ (2.28)	$ 2.41	$ 1.21	$ 2.06
Diluted	$ (2.28)	$ 2.17	$ 1.09	$ 1.87
Weighted average common shares outstanding:
Basic	2,192,470	1,088,251	1,669,578	1,053,912
Diluted	2,192,470	2,536,900	3,084,084	2,377,211

Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Net income (loss)	$ (3,749)	$ 32,111	$ 18,208	$ 28,952
Other comprehensive loss:
Net unrealized losses on marketable securities, net of tax of $0	(3)	(17)	(17)	(14)
Total other comprehensive loss	(3)	(17)	(17)	(14)
Comprehensive income (loss)	$ (3,752)	$ 32,094	$ 18,191	$ 28,938

- Definition

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References + Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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+ Details

- Definition

Net of tax amount of unrealized holding gain (loss) before reclassification adjustments and transfers on available-for-sale securities.

+ References

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+ Details

Statements of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Net unrealized losses on marketable securities, tax	$ 0	$ 0	$ 0	$ 0

Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
Statements of Cash Flows - USD ($) $ in Thousands	Mar. 31, 2013	Mar. 31, 2012
Cash flows from operating activities
Net income	$ 18,208	$ 28,952
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	87	98
Non-cash interest expense	16
Change in fair value of warrant liability	(234)	(10)
Stock-based compensation expense	538	86
Gain on disposal of property and equipment		(55)
Amortization of premium on marketable securities	401	126
Change in operating assets and liabilities:
Accounts receivable	380	176
Unbilled receivables	1,125	(1,242)
Prepaid expenses and other current assets	271	(6)
Other assets		(32)
Accounts payable	(469)	(117)
Accrued expenses	(1,369)	139
Deferred revenue	98
Other long-term liabilities	26	38
Net cash provided by operating activities	19,078	28,153
Cash flows from investing activities
Purchases of property and equipment	(352)	(94)
Proceeds from sales of property and equipment		58
Purchases of marketable securities	(45,706)	(29,549)
Sales of marketable securities	2,454
Maturities of marketable securities	30,245	14,050
Change in restricted cash		1,140
Net cash used in investing activities	(13,359)	(14,395)
Cash flows from financing activities
Proceeds from exercise of stock options	415	107
Proceeds from initial public offering, net of commissions	59,892
Payments of initial public offering costs	(2,073)
Net cash provided by financing activities	58,234	107
Net increase in cash and cash equivalents	63,953	13,865
Cash and cash equivalents at beginning of period	10,511	6,837
Cash and cash equivalents at end of period	74,464	20,702
Supplemental disclosure of noncash financing activities:
Accretion of redeemable convertible preferred stock to redemption value	2,526	$ 2,705
Initial public offering costs included in accounts payable or accrued expenses	1,466
Conversion of preferred stock into common stock	$ 161,808

Nature of the Business and Basis of Presentation

6 Months Ended

Mar. 31, 2013

Nature of the Business and Basis of Presentation

Nature of the Business and Basis of Presentation

Enanta Pharmaceuticals, Inc. (the “Company”), incorporated in Delaware in 1995, is a research and development-focused biotechnology company that uses its chemistry-driven approach and drug discovery capabilities to create small molecule drugs in the infectious disease field. The Company is developing novel protease, NS5A, cyclophilin and nucleotide polymerase inhibitors targeted against the hepatitis C virus (“HCV”). Additionally, the Company has created a new class of bridged bicyclic antibiotics known as Bicyclolides that overcomes bacterial resistance. Antibacterial focus areas include “superbugs,” respiratory tract infections, and intravenous and oral treatments for hospital and community Methicillin-resistant Staphylococcus aureus (“MRSA”).

The Company is subject to risks common to companies in the biotechnology industry including, but not limited to, new technological innovations, dependence on collaborative arrangements, protection of proprietary technology, dependence on key personnel, compliance with government regulations and the need to obtain additional financing. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel infrastructure, and extensive compliance reporting capabilities.

On March 26, 2013 the Company completed an initial public offering (“IPO”) of its common stock, which resulted in the sale of 4,600,000 shares at a price of $14.00 per share. The Company received net proceeds from the IPO of approximately $59,892 based upon the price of $14.00 per share and after deducting underwriting discounts and commissions paid by the Company.

Unaudited Interim Financial Information

The balance sheet at September 30, 2012 was derived from audited financial statements, but does not include all disclosures required by GAAP. The accompanying unaudited financial statements as of March 31, 2013 and for the three and six months ended March 31, 2013 and 2012 have been prepared by the Company, pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. These financial statements should be read in conjunction with the Company’s audited financial statements and the notes thereto for the year ended September 30, 2012 included in the Company’s final prospectus filed pursuant to rule 424(b) under the Securities Act of 1933, as amended, filed with the Securities and Exchange Commission on March 21, 2013.

In the opinion of management, all adjustments, consisting only of normal recurring adjustments necessary for a fair statement of the Company’s financial position as of March 31, 2013 and results of operations for the three and six months ended March 31, 2013 and 2012 and cash flows for the six months ended March 31, 2013 and 2012 have been made. The results of operations for the three and six months ended March 31, 2013 are not necessarily indicative of the results of operations that may be expected for the year ending September 30, 2013.

The accompanying financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). All dollar amounts in the financial statements and in the notes to the consolidated financial statements, except share and per share amounts, are in thousands unless otherwise indicated.

Summary of Significant Accounting Policies

6 Months Ended

Mar. 31, 2013

Summary of Significant Accounting Policies

Summary of Significant Accounting Policies

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Significant estimates and assumptions reflected in these financial statements include, but are not limited to, management’s judgments of separate units of accounting and best estimate of selling price of those units of accounting within its revenue arrangements; the valuation of common stock, warrants and stock-based awards; the useful lives of property and equipment; and the accounting for income taxes, including uncertain tax positions and the valuation of net deferred tax assets. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Actual results could differ from the Company’s estimates.

Revenue Recognition

The Company’s revenue is generated primarily through collaborative research and license agreements. The terms of these agreements contain multiple deliverables, which may include (i) licenses, (ii) research and development activities, and (iii) participation in joint research and development steering committees. The terms of these agreements may include nonrefundable upfront license fees, payments for research and development activities, payments based upon the achievement of certain milestones, and royalty payments based on product sales derived from the collaboration. In all instances, revenue is recognized only when the price is fixed or determinable, persuasive evidence of an arrangement exists, delivery has occurred or the services have been rendered, collectibility of the resulting receivable is reasonably assured, and the Company has fulfilled its performance obligations under the contract.

For multiple element agreements entered into or materially modified after October 1, 2011, the Company applies the principles included in Accounting Standards Update (“ASU”) No. 2009-13, Multiple-Deliverable Revenue Arrangements (“ASU 2009-13”) to account for revenue. Under this guidance the selling prices of deliverables under the arrangement may be derived using third-party evidence (“TPE”) or a best estimate of selling price (“BESP”), if vendor specific objective evidence (“VSOE”) is not available. The objective of BESP is to determine the price at which the Company would transact a sale if the element within the license agreement was sold on a standalone basis. Establishing BESP involves management’s judgment and considers multiple factors, including market conditions and company-specific factors including those factors contemplated in negotiating the agreements as well as internally developed models that include assumptions related to market opportunity, discounted cash flows, estimated development costs, probability of success, and the time needed to commercialize a product candidate pursuant to the license. In validating the Company’s BESP, the Company considers whether changes in key assumptions used to determine the BESP will have a significant effect on the allocation of the arrangement consideration between the multiple deliverables. Deliverables under the arrangement are separate units of accounting if (i) the delivered item has value to the customer on a standalone basis, and (ii) if the arrangement includes a general right of return relative to the delivered item, delivery or performance of the undelivered item is considered probable and substantially within the control of the Company. The arrangement consideration that is fixed or determinable at the inception of the arrangement is allocated to the separate units of accounting based on their relative selling prices. The appropriate revenue recognition model is applied to each element, and revenue is accordingly recognized as each element is delivered. The Company may exercise significant judgment in determining whether a deliverable is a separate unit of accounting.

In determining the separate units of accounting, the Company evaluates whether the license has standalone value to the collaborator based on consideration of the relevant facts and circumstances for each arrangement. Factors considered in this determination include the research and development capabilities of the collaborator and the availability of relevant research expertise in the marketplace. In addition, the Company considers whether or not (i) the collaborator can use the license for its intended purpose without the receipt of the remaining deliverables, (ii) the value of the license is dependent on the undelivered items, and (iii) the collaborator or other vendors can provide the undelivered items.

Under a collaborative research and license agreement, a steering committee is typically responsible for overseeing the general working relationships, determining the protocols to be followed in the research and development performed, and evaluating the results from the continued development of the product in order to determine the clinical studies to be performed. The Company evaluates whether its participation in joint research and development steering committees is a substantive obligation or whether the services are considered inconsequential or perfunctory. The Company’s participation on a steering committee is considered “participatory” and therefore accounted for as a separate element when the collaborator requires the participation of the Company to ensure all elements of an arrangement are maximized. Steering committee services that are considered participatory are combined with other research services or performance obligations required under an arrangement, if any, in determining the level of effort required in an arrangement and the period over which the Company expects to complete its aggregate performance obligations. Alternatively, the Company’s participation on a steering committee is considered “protective” and therefore not accounted for as a separate element in a case where the Company can exercise or control when to be involved at its own discretion. Factors the Company considers in determining if its participation in a joint steering committee is participating or protective include: (i) which party negotiated or requested the steering committee, (ii) how frequently the steering committee meets, (iii) whether or not there are any penalties or other recourse if the Company does not attend the steering committee meetings, (iv) which party has decision making authority on the steering committee, and (v) whether or not the collaborator has the requisite experience and expertise associated with the research and development of the licensed intellectual property.

For agreements entered into prior to October 1, 2011, the Company accounted for the multiple elements within the agreements as a single unit of accounting and all payments received were recognized as revenue over the estimated period of performance of the entire arrangement as the Company was not able to separately recognize revenue for the elements under the provisions of previously applicable revenue recognition guidance.

For all periods presented, whenever the Company determines that an element is delivered over a period of time, revenue is recognized using either a proportional performance model or a straight-line model over the period of performance, which is typically the research and development term. Full-time equivalents (“FTEs”) are typically used as the measure of performance. At each reporting period, the Company reassesses its cumulative measure of performance and makes appropriate adjustments, if necessary. The Company recognizes revenue using the proportional performance model whenever the Company can make reasonably reliable estimates of the level of effort required to complete its performance obligations under an arrangement. Revenue recognized under the proportional performance model at each reporting period is determined by multiplying the total expected payments under the contract (excluding royalties and payments contingent upon achievement of milestones) by the ratio of the level of effort incurred to date to the estimated total level of effort required to complete the performance obligations under the arrangement. Revenue is limited to the lesser of the cumulative amount of payments received or the cumulative amount of revenue earned, as determined using the proportional performance model as of each reporting period. Alternatively, if the Company cannot make reasonably reliable estimates the level of effort required to complete its performance obligations under an arrangement, then revenue under the arrangement is recognized on a straight-line basis over the period expected to complete the Company’s performance obligations. If and when a contingent milestone payment is earned, the additional consideration to be received is allocated to the separate units of accounting in the arrangement based on their relative selling prices at the inception of the arrangement. Revenue is limited to the lesser of the cumulative amount of payments received or the cumulative amount of revenue earned, as determined on a straight-line basis as of the period end date. If the Company cannot reasonably estimate when its performance obligation period ends, then revenue is deferred until the Company can reasonably estimate when the performance obligation period ends.

Royalty revenue, if any, is recognized based on contractual terms when reported sales are reliably measurable and collectibility is reasonably assured, provided that there are no performance obligations then remaining. To date, none of the Company’s products have been approved, and therefore the Company has not earned any royalty revenue from product sales.

During the three and six months ended March 31, 2013 and 2012 the Company also generated revenue from a government contract that reimburses the Company for certain allowable costs for the funded project. Revenue from the government contract is recognized when the related service is performed. The related costs incurred by the Company under the government contract are included in research and development expense in the statements of operations.

Amounts received prior to satisfying all revenue recognition criteria are recorded as deferred revenue in the accompanying balance sheets. Amounts not expected to be recognized as revenue within the next twelve months of the balance sheet date are classified as long-term deferred revenue.

In the event that a collaborative research and license agreement is terminated and the Company then has no further performance obligations, the Company recognizes as revenue any amounts that had not previously been recorded as revenue but were classified as deferred revenue at the date of such termination.

Recently Issued and Adopted Accounting Pronouncements

In February 2013, the FASB issued ASU No. 2013-02, Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income (“ASU 2013-02”). This newly issued accounting standard requires an entity to provide information about the amounts reclassified out of accumulated other comprehensive income by component. In addition, an entity is required to present, either on the face of the statement where net income is presented or in the notes, significant amounts reclassified out of accumulated other comprehensive income by the respective line items of net income but only if the amount reclassified is required under U.S. GAAP to be reclassified to net income in its entirety in the same reporting period. For other amounts that are not required under U.S. GAAP to be reclassified in their entirety to net income, an entity is required to cross-reference to other disclosures required under U.S. GAAP that provide additional detail about those amounts. ASU 2013-02 is effective for fiscal years and interim periods within those years beginning after December 15, 2012 and will become effective for the Company on October 1, 2013. The Company does not believe the adoption of this standard will have an impact on the Company’s financial position or results of its operations.

Other accounting standards that have been issued by the FASB or other standards-setting bodies that do not require adoption until a future date are not expected to have a material impact on the Company’s financial statements upon adoption.

Fair Value of Financial Assets and Liabilities

6 Months Ended

Mar. 31, 2013

Fair Value of Financial Assets and Liabilities

Fair Value of Financial Assets and Liabilities

The following tables present information about the Company’s financial assets and liabilities that were subject to fair value measurement on a recurring basis as of March 31, 2013 and September 30, 2012 and indicate the fair value hierarchy of the valuation inputs utilized to determine such fair value:


	Fair Value Measurements as of March 31, 2013 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents	$	72,016	$	—	$	—	$	72,016
Marketable securities		1,010		46,266		—		47,276

	$	73,026	$	46,266	$	—	$	119,292

Liabilities:
Warrant liability	$	—	$	—	$	1,767	$	1,767

	$	—	$	—	$	1,767	$	1,767


	Fair Value Measurements as of September 30, 2012 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents	$	6,471	$	—	$	—	$	6,471
Marketable securities		1,015		33,892		—		34,907

	$	7,486	$	33,892	$	—	$	41,378

Liabilities:
Warrant liability	$	—	$	—	$	2,001	$	2,001

	$	—	$	—	$	2,001	$	2,001

Cash equivalents at March 31, 2013 and September 30, 2012 consist of money market funds.

During the three or six months ended March 31, 2013 and 2012, there were no transfers between Level 1, Level 2 and Level 3.

As of September 30, 2012, the warrant liability is comprised of the values of warrants for the purchase of Series E redeemable convertible preferred stock and warrants for the purchase of Series 1 nonconvertible preferred stock, measured at fair value, and are based on significant inputs not observable in the market, which represents a Level 3 measurement within the fair value hierarchy. The Company’s valuation of the warrant liability utilized the Black-Scholes option-pricing model, which incorporates assumptions and estimates to value the Series E warrants and Series 1 warrants. Related to the valuation of warrants for the purchase of Series 1 nonconvertible preferred stock, the most significant quantitative elements associated with the Company’s Level 3 inputs impacting fair value measurement was the fair value per share of the underlying Series 1 nonconvertible preferred stock. The Company determined that the fair value of the Series 1 nonconvertible preferred stock equals its stated liquidation preference of $1.00 per share and was $1,981 as of September 30, 2012. Since the Series 1 nonconvertible preferred stock ranks senior to all other classes of stock and its liquidation preference is small relative to the Company’s equity value, the probability of a 100% payout on the Series 1 nonconvertible preferred stock was considered to be high. The fair value of warrants for the purchase of Series E redeemable convertible preferred stock was $20, as of September 30, 2012. The Company assesses these assumptions and estimates on a quarterly basis as additional information impacting the assumptions is obtained. Changes in the fair value of the warrant liability are recognized in the statements of operations.

As of March 31, 2013, the warrant liability consists solely of the warrants for the purchase of Series 1 nonconvertible preferred stock. The Series E warrants expired during the six months ended March 31, 2013. As of March 31, 2013, the Company utilized a probability-weighted valuation model which takes into consideration various outcomes that may require the Company to transfer assets upon exercise and determined that the fair value of the Series 1 warrants was $1,767.

The following table provides a rollforward of the aggregate fair values of the Company’s warrants for the purchase of Series E preferred stock and Series 1 nonconvertible preferred stock for which fair value is determined by Level 3 inputs:


Balance, September 30, 2012	$	2,001
Warrants expired		(20	)
Decrease in fair value		(214	)

Balance, March 31, 2013	$	1,767

- 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 Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14172-108612

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13537-108611

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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-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13504-108611

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13433-108611

Reference 7: 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 8: 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 9: 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 10: 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 11: 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 12: 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 13: 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.

+ Details

Marketable Securities

6 Months Ended

Mar. 31, 2013

Marketable Securities

Marketable Securities

As of March 31, 2013 and September 30, 2012, the fair value of available-for-sale marketable securities by type of security was as follows:


	March 31, 2013
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Commercial paper	$	10,186	$	—	$	—		$	10,186
Corporate bonds		28,084		5		(14	)		28,075
U.S. Agency bonds		4,555		—		—			4,555
Certificate of deposit		3,450		—		—			3,450
U.S. Treasury notes		1,008		2		—			1,010

	$	47,283	$	7	$	(14	)	$	47,276


	September 30, 2012
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Commercial paper	$	8,143	$	—	$	—		$	8,143
Corporate bonds		25,741		9		(1	)		25,749
U.S. Treasury notes		1,013		2		—			1,015

	$	34,897	$	11	$	(1	)	$	34,907

At March 31, 2013, marketable securities consisted of investments that mature within one year, with the exception of certain U.S. Agency and corporate bonds, which have maturities within two years and an aggregate fair value of $12,629.

- Definition

The entire disclosure for investments in certain debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-Glossary Debt Security
-URI http://asc.fasb.org/extlink&oid=6509901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27161-111563

Reference 9: http://www.xbrl.org/2003/role/presentationRef
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Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 3, 19, 20, 21, 22, 137
-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.

+ Details

Accrued Expenses and Other Long-Term Liabilities

6 Months Ended

Mar. 31, 2013

Accrued Expenses and Other Long-Term Liabilities

Accrued Expenses and Other Long-Term Liabilities

Accrued expenses (current) and other long-term liabilities consisted of the following as of March 31, 2013 and September 30, 2012:


	March 31, 2013		September 30, 2012

Accrued expenses:
Accrued payroll and related expenses	$	493	$	1,305
Accrued vendor manufacturing		23		1,330
Accrued professional fees		629		718
Accrued third-party license fees		728		222
Accrued other		592		291

	$	2,465	$	3,866

Other long-term liabilities:
Accrued rent expense	$	101	$	75
Present value of accrued third-party license fees		433		423

	$	534	$	498

Collaboration Agreements

6 Months Ended

Mar. 31, 2013

Collaboration Agreements

Collaboration Agreements

AbbVie Collaboration

On November 27, 2006, the Company entered into a Collaborative Development and License Agreement (the “Abbott Agreement” or “AbbVie Agreement”) with Abbott Laboratories (“Abbott”) to identify, develop and commercialize HCV NS3 and NS3/4A protease inhibitor compounds, including ABT-450. The agreement, which was amended in January and December 2009, was assigned to AbbVie Inc. (“AbbVie”) on January 1, 2013 in connection with Abbott’s transfer of its research-based pharmaceuticals business to AbbVie. Under the terms of the AbbVie Agreement, as amended, AbbVie paid to the Company upfront license payments and FTE reimbursements to fund research activities. The Company is also eligible to receive milestone payments for the successful development by AbbVie of one or more HCV compounds as well as tiered royalties per product ranging from the low double digits up to twenty percent, or on a blended basis from the low double digits up to the high teens, on net sales by AbbVie allocable to the collaboration’s protease inhibitors. Deliverables under the AbbVie Agreement included a license, research services and participation on a steering committee. The Company concluded that all deliverables under the AbbVie Agreement should be treated as a single unit of accounting. Accordingly, revenue was recognized using the proportional performance model over the period during which the Company performed research services. The Company completed all remaining obligations under the agreement as of June 2011. All milestone payments received after June 2011 are recognized as revenue when each milestone is achieved by AbbVie.

Through June 2011, under the AbbVie Agreement the Company had received upfront license payments, research funding, and milestone payments totaling $92,450, all of which has been recognized as revenue as of June 30, 2011. In December 2012, the Company received an additional $15,000 milestone payment under the AbbVie Agreement as a result of AbbVie’s initiation of dosing in a Phase 3 clinical trial involving ABT-450. This amount was recognized as revenue during the three months ended December 31, 2012.

During the three months ended March 31, 2013 and 2012, the Company recognized no revenue related to this agreement. During the six months ended March 31, 2013 and 2012, the Company recognized revenue of $15,000 and $0, respectively.

As of March 31, 2013, the Company is eligible to receive additional future milestone payments totaling up to $40,000 upon AbbVie’s achievement of regulatory filing milestones for the first protease inhibitor product resulting from its collaboration and additional milestone payments totaling up to $155,000 upon AbbVie’s achievement of commercial regulatory approval milestones in selected world markets. The Company is also eligible to receive additional milestone payments totaling up to $80,000 upon AbbVie’s achievement of similar commercial regulatory approval milestones for each additional product containing a new protease inhibitor.

Novartis Collaboration

On February 16, 2012, the Company entered into a license and collaboration agreement with Novartis (the “Novartis Agreement”) for the development, manufacture and commercialization of its lead development candidate, EDP-239, from its NS5A HCV inhibitor program. Under the terms of the Novartis Agreement, Novartis agreed to pay a nonrefundable upfront fee to the Company and reimbursement of manufacturing and quality assurance expenses related to EDP-239 totaling $34,442. Under the agreement, the Company is eligible to receive aggregate milestone payments of up to $406,000 upon Novartis’ initiation of clinical trials, achievement of regulatory approvals, and/or net sales of products containing the Company’s NS5A inhibitors. The Company is also eligible to receive tiered royalties ranging on a blended basis from the low double digits up to the high teens on net product sales by Novartis allocable to the collaboration’s NS5A inhibitors. Under the agreement, a clinical milestone payment of $11,000 was due to the Company upon Novartis’ initiation of dosing in the first Phase 1 clinical trial involving EDP-239 or another NS5A inhibitor, and was received by the Company in January 2013. An additional milestone payment of $15,000 will be due upon Novartis’ initiation of the first Phase 2 clinical trial using a combination containing an NS5A inhibitor. In addition, Novartis agreed to fund research activities for one year commencing February 2012, up to a total of $1,800. In March 2013, the agreement was amended to extend research funding for an additional six months through August 2013 at the same reimbursement rate.

The Company determined that the deliverables under the Novartis Agreement were the license and the research services. As each of these deliverables had standalone value it was determined that they each represented a separate unit of accounting. Arrangement consideration was allocated between the license and research services based on their relative selling prices using best estimate of selling price.

During the three months ended March 31, 2013 and 2012 the Company recognized total revenue of $465 and $34,667, respectively, related to the delivery of the license and the performance of the research services. During the six months ended March 31, 2013 and 2012, the Company recognized total revenue of $11,877 and $34,667, respectively, under the Novartis Agreement.

NIAID Contract

On September 30, 2011, the Company entered into a contract with the National Institute of Allergy and Infectious Diseases (“NIAID”), a division of the National Institutes of Health (“NIH”), which could provide up to $42,700 in development funding to the Company over a five-year period. The contract will fund the preclinical and clinical development of a new class of bridged bicyclic antibiotics known as Bicyclolides to be used as medical countermeasures against multiple biodefense Category A and B bacteria.

The contract has an initial term of 30 months ending on March 30, 2014. NIAID has the option to extend the contract up to six times. If each extension option is exercised, the contract would be extended until September 30, 2016. The initial award under the initial term was $14,300, with the possibility of up to a total of $42,700 if each option period is exercised by NIAID.

The Company recognizes revenue under this agreement as development services are performed in accordance with the funding agreement. During the three months ended March 31, 2013 and 2012, $731 and $1,898 of revenue, respectively, was recognized under this agreement. During the six months ended March 31, 2013 and 2012, the Company recognized revenue of $2,178 and $2,639, respectively, under this agreement.

Stockholders' Equity

6 Months Ended

Mar. 31, 2013

Stockholders' Equity

Stockholders’ Equity

On March 1, 2013, the Company effected an increase in the number of authorized shares of its common stock from 70,000,000 to 100,000,000 shares. On March 1, 2013, the Company effected a 1-for-4.31 reverse stock split of its issued and outstanding shares of common stock and a proportional adjustment to the existing conversion ratio for each series of Redeemable Convertible Preferred Stock and Convertible Preferred Stock. Accordingly, all share and per share amounts for all periods presented in these financial statements and notes thereto have been adjusted retroactively, where applicable, to reflect the reverse stock split and adjustment of the preferred share conversion ratios.

Upon closing of the initial public offering, all outstanding shares of the Company’s redeemable convertible preferred stock and convertible preferred stock were converted into 11,656,875 shares of common stock.

Warrants to Purchase Series E Preferred Stock

Warrants for the purchase of Series E redeemable convertible preferred stock (“Series E preferred stock”) were issued by the Company in fiscal 2002 and fiscal 2004 during various financings. As these warrants are financial instruments that could have required a transfer of assets because of the redemption feature at the option of the holders of the Series E preferred stock, these warrants were classified as liabilities on the Company’s balance sheet.

As of September 30, 2012, warrants for the purchase of 12,500 shares of Series E preferred stock remained outstanding. These warrants expired during the six months ended March 31, 2013.

Warrants to Purchase Series 1 Preferred Stock

In October and November 2010, a total of 1,999,989 warrants to purchase Series 1 nonconvertible preferred stock were issued. These warrants expire on October 4, 2017. As these warrants are free-standing financial instruments that may require the Company to transfer assets upon exercise, these warrants are classified as liabilities. These warrants had a fair value of $1,280 upon issuance. The Company is required to remeasure the fair value of these preferred stock warrants at each reporting date, with any adjustments recorded within the change in fair value of warrant liability included in other income (expense) in the statement of operations. The warrants were remeasured at each reporting period, resulting in net income of $214 and $0 for the three and six months ended March 31, 2013 and 2012, respectively. As of March 31, 2013 and September 30, 2012, the total fair value of the Series 1 nonconvertible preferred stock warrants was $1,767 and $1,981, respectively.

- 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 FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(d),(e))
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 14: http://www.xbrl.org/2003/role/presentationRef
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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 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
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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 16: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 17: http://www.xbrl.org/2003/role/presentationRef
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-Number 210
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-Article 4

Reference 18: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
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Reference 19: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section E

Reference 20: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Article 4

Reference 21: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section C

Reference 22: 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 23: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

+ Details

Stock-Based Awards

6 Months Ended

Mar. 31, 2013

Stock-Based Awards

Stock-Based Awards

1995 Equity Incentive Plan

The 1995 Equity Incentive Plan (the “1995 Plan”) provides for the Company to sell or issue common stock or restricted common stock, or to grant incentive stock options or nonqualified stock options for the purchase of common stock, to employees, members of the board of directors and consultants of the Company. Sales, issuances or grants of shares entitle the holder to purchase common stock from the Company, for a specified exercise price, during a period specified by the applicable equity award agreement. The 1995 Plan is administered by the board of directors and exercise prices, vesting and other restrictions are all determined at their discretion. Options granted under the 1995 Plan to non-executive employees generally vest 25% per year and expire after ten years; options granted to executive employees generally vest over one to four years; and options granted to the board of directors vest over a two-year period. On January 17, 2013, the Company’s stockholders approved an amendment to the 1995 Equity Incentive Plan to increase the number of shares of common stock reserved for issuance under the plan by 232,018 shares to 2,772,777 shares. Upon closing of the Company’s initial public offering, 26,742 shares reserved and not then subject to outstanding options were transferred to the 2012 Plan, and no further awards will be made under the 1995 Plan.

2012 Equity Incentive Plan

On January 17, 2013, the Company’s stockholders approved the 2012 Equity Incentive Plan (the “2012 Plan”), which became effective immediately prior to the closing of the Company’s initial public offering. The 2012 Plan permits the Company to sell or issue common stock or restricted common stock, to grant incentive stock options or nonqualified stock options for the purchase of common stock, or to grant restricted stock units, stock appreciation rights or other cash incentive awards, to employees, members of the board of directors and consultants of the Company. The total number of shares of common stock that may be issued under the plan is 348,355 shares, including 26,742 shares incorporated from the 1995 Plan that were reserved and not subject to outstanding options as of the closing of the Company’s initial public offering. The number of shares of common stock that may be issued under the plan is also subject to increase by the number of shares forfeited under any options terminated and not exercised under the 1995, plus an increase in shares on the first day of each fiscal year by the lowest of (i) 3% of the Company’s outstanding shares of common stock as of that date, (ii) 2,088,167 shares of common stock, or (iii) an amount determined by the board of directors.

During the three months ended March 31, 2013, the Company granted to certain executives 167,052 options that vest upon the achievement of certain performance-based targets. The fair value of these options at the grant date was $1,487.

Through March 31, 2013, the Company recorded approximately $5 of stock compensation expense related to these awards for the portion of the service period incurred related to performance-based targets that were considered probable.

Employee Stock Purchase Plan

On January 3, 2013, the Company’s stockholders approved the Employee Stock Purchase Plan (the “ESPP”). A total of 185,614 shares of common stock were reserved for issuance under this plan, which became effective immediately prior the closing of the Company’s initial public offering. As of March 31, 2013, the first offering period under the ESPP had not commenced and no shares have been issued.

Stock Option Valuation

The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes option-pricing model. The Company historically has been a private company and lacks sufficient company-specific historical and implied volatility information. Therefore, it estimates its expected stock volatility based on the historical volatility of its publicly traded peer companies and expects to continue to do so until such time as it has adequate historical data regarding the volatility of its own traded stock price. The expected term of the Company’s stock options has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future. The relevant data used to determine the value of the stock option grants is as follows, presented on a weighted average basis:


	Three Months Ended March 31,				Six Months Ended March 31,
	2013			2012	2013			2012

Risk-free interest rate		1.08	%	n/a		1.03	%	n/a
Expected term (in years)		6.16		n/a		6.10		n/a
Expected volatility		71	%	n/a		73	%	n/a
Expected dividend yield		0	%	n/a		0	%	n/a

The Company recognizes compensation expense for only the portion of awards that are expected to vest. In developing a forfeiture rate estimate, the Company has considered its historical experience to estimate pre-vesting forfeitures for service-based awards. The impact of a forfeiture rate adjustment will be recognized in full in the period of adjustment, and if the actual forfeiture rate is materially different from the Company’s estimate, the Company may be required to record adjustments to stock-based compensation expense in future periods.

As required by the 1995 Plan and 2012 Plan, the exercise price for awards granted is not to be less than the fair value of common shares as estimated by the Company as of the date of grant. For periods prior to the initial public offering of common stock, the Company valued its common stock by taking into consideration its most recently available valuation of common shares performed by management and the board of directors as well as additional factors which may have changed since the date of the most recent contemporaneous valuation through the date of grant.

The following table summarizes stock option activity during the six months ended March 31, 2013:


	Shares Issuable Under Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
				(In years)
Outstanding as of September 30, 2012		1,771,471		$	2.08		4.1	$	19,911
Granted		350,682			14.03
Exercised		(427,590	)		0.97
Expired		(2,864	)		2.59

Outstanding as of March 31, 2013		1,691,699		$	4.84		5.3	$	22,609

Options vested and expected to vest as of March 31, 2013		1,679,722		$	4.77		5.3	$	22,559

Options exercisable as of March 31, 2013		1,232,478		$	2.08		3.7	$	19,870

The Company recorded stock-based compensation expense for the three and six months ended March 31, 2013 and 2012 in the following expense categories:


	Three Months Ended March 31,				Six Months Ended March 31,
	2013		2012		2013		2012

Research and development	$	85	$	13	$	179	$	29
General and administrative		172		18		359		57

	$	257	$	31	$	538	$	86

As of March 31, 2013, the Company had an aggregate of $1,721 of unrecognized stock-based compensation cost, which is expected to be recognized over a weighted average period of 2.8 years.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 50
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6406099&loc=d3e25284-112666

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6418621&loc=d3e17540-113929

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5444-113901

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64, 65, A240
-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 AICPA
-Name Statement of Position (SOP)
-Number 93-6
-Paragraph 53
-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.

+ Details

Net Income (Loss) Per Share

6 Months Ended

Mar. 31, 2013

Net Income (Loss) Per Share

Net Income (Loss) Per Share

Basic and diluted net income (loss) per share attributable to common stockholders was calculated as follows for the three and six months ended March 31, 2013 and 2012:


	Three Months Ended March 31,						Six Months Ended March 31,
	2013			2012			2013			2012

Basic net income (loss) per share attributable to common stockholders:
Numerator:
Net income (loss)	$	(3,749	)	$	32,111		$	18,208		$	28,952
Accretion of redeemable convertible preferred stock to redemption value		(1,244	)		(1,331	)		(2,526	)		(2,705	)
Net income attributable to participating securities		—			(28,152	)		(13,670	)		(24,071	)

Net income (loss) attributable to common stockholders	$	(4,993	)	$	2,628		$	2,012		$	2,176

Denominator:
Weighted average common shares outstanding—basic		2,192,470			1,088,251			1,669,578			1,053,912

Net income (loss) per share attributable to common stockholders—basic	$	(2.28	)	$	2.41		$	1.21		$	2.06


Diluted net income (loss) per share attributable to common stockholders:
Numerator:
Net income (loss)	$	(3,749	)	$	32,111		$	18,208		$	28,952
Accretion of redeemable convertible preferred stock to redemption value		(1,244	)		(1,331	)		(2,526	)		(2,705	)
Net income attributable to participating securities		—			(25,279	)		(12,329	)		(21,802	)

Net income (loss) attributable to common stockholders—diluted	$	(4,993	)	$	5,501		$	3,353		$	4,445

Denominator:
Weighted average common shares outstanding—basic		2,192,470			1,088,251			1,669,578			1,053,912
Dilutive effect of common stock equivalents		—			1,448,649			1,414,506			1,323,299

Weighted average common shares outstanding—diluted		2,192,470			2,536,900			3,084,084			2,377,211

Net income (loss) per share attributable to common stockholders—diluted	$	(2.28	)	$	2.17		$	1.09		$	1.87

Stock options for the purchase of 245,225 weighted average shares were excluded from the computation of diluted net income per share attributable to common stockholders for the three months ended March 31, 2013 and stock options for the purchase of 126,489 weighted average shares were excluded from the computation of diluted net income per share attributable to common stockholders for the six months ended March 31, 2013 because those options had an anti-dilutive impact due to the assumed proceeds per share using the treasury stock method being greater than the average fair value of the Company’s common shares for those periods. Stock options for the purchase of 1,540,845 weighted average shares were excluded from the computation of diluted net loss per share attributable to common stockholders for the three months ended March 31, 2013 because those options had an anti-dilutive impact due to the net loss attributable to common stockholders incurred for the period.

There were no outstanding common stock equivalents that had an anti-dilutive impact on net income per share attributable to common stockholders for the three or six months ended March 31, 2012.

Commitments and Contingencies

6 Months Ended

Mar. 31, 2013

Commitments and Contingencies

10.

Commitments and Contingencies

Leases

The Company has an office and laboratory lease that expires in September 2018. Payment escalation as specified in the lease agreement is accrued such that rent expense is recognized on a straight-line basis over the terms of occupancy. The Company recorded rent expense of $237 for the three months ended March 31, 2013 and 2012, and $474 for the six months ended March 31, 2013 and 2012.

In connection with the lease, the Company has outstanding a $436 letter of credit, collateralized by a money market account. As of March 31, 2013 and September 30, 2012, the Company classified $436 related to the letter of credit as restricted cash.

Intellectual Property License

The Company has a non-exclusive intellectual property license agreement under which it is required to pay the licensor future license fees of $250, $250 and $200 in fiscal years 2013, 2014 and 2015, respectively. In addition, the Company is required to pay (1) annual maintenance fees of $105 for each year that the agreement remains in effect in order to maintain the right to use the license, and (2) a one-time fee of $50 in each circumstance in which the Company provides the licensed intellectual property to one of its collaborators with the prior consent of the licensor. As of March 31, 2013, the Company had accrued expense relating to this obligation of $661 of which $228 was included in accrued expenses and $433 was included in other long-term liabilities.

Litigation and Contingencies Related to Use of Intellectual Property

As of March 31, 2013 the Company was aware of a potential license it may need to acquire with respect to patents it used, or may have used, in prior years or periods. During the three months ended March 31, 2013, the Company first determined that the probable license costs could be reasonably estimated. As a result, during that period, the Company recorded an expense and a corresponding accrued liability of $500, based on its best estimate at that date of this contingent liability.

From time to time, the Company may become subject to legal proceedings, claims and litigation arising in the ordinary course of business. The Company currently is not a party to any threatened or pending litigation. However, third parties might allege that the Company or its collaborators are infringing their patent rights or that the Company is otherwise violating their intellectual property rights. Such third parties may resort to litigation against the Company or its collaborators, which the Company has agreed to indemnify. With respect to some of these patents, the Company expects that it will be required to obtain licenses and could be required to pay license fees or royalties, or both. These licenses may not be available on acceptable terms, or at all. A costly license, or inability to obtain a necessary license, could have a material adverse effect on the Company’s financial condition, results of operations or cash flows. The Company accrues contingent liabilities when it is probable that future expenditures will be incurred and such expenditures can be reasonably estimated.

Indemnification Agreements

In the ordinary course of business, the Company may provide indemnifications of varying scope and terms to customers, vendors, lessors, business partners, and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements, from services to be provided by the Company, or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. Despite the fact that the Company has obtained insurance coverage for certain of these indemnifications, the maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company does not believe that the outcome of any claims under indemnification arrangements will have a material effect on its financial position, results of operations or cash flows, and it has not accrued any liabilities related to such obligations in its financial statements as of March 31, 2013.

- Definition

The entire disclosure for commitments and contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6449706&loc=d3e16207-108621

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14435-108349

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6394976&loc=d3e25287-109308

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 14
-Paragraph 3
-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 5
-Paragraph 9, 10, 11, 12
-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.

+ Details

Summary of Significant Accounting Policies (Policies)	6 Months Ended
Summary of Significant Accounting Policies (Policies)	Mar. 31, 2013
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Significant estimates and assumptions reflected in these financial statements include, but are not limited to, management’s judgments of separate units of accounting and best estimate of selling price of those units of accounting within its revenue arrangements; the valuation of common stock, warrants and stock-based awards; the useful lives of property and equipment; and the accounting for income taxes, including uncertain tax positions and the valuation of net deferred tax assets. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Actual results could differ from the Company’s estimates.
Revenue Recognition	Revenue Recognition The Company’s revenue is generated primarily through collaborative research and license agreements. The terms of these agreements contain multiple deliverables, which may include (i) licenses, (ii) research and development activities, and (iii) participation in joint research and development steering committees. The terms of these agreements may include nonrefundable upfront license fees, payments for research and development activities, payments based upon the achievement of certain milestones, and royalty payments based on product sales derived from the collaboration. In all instances, revenue is recognized only when the price is fixed or determinable, persuasive evidence of an arrangement exists, delivery has occurred or the services have been rendered, collectibility of the resulting receivable is reasonably assured, and the Company has fulfilled its performance obligations under the contract. For multiple element agreements entered into or materially modified after October 1, 2011, the Company applies the principles included in Accounting Standards Update (“ASU”) No. 2009-13, Multiple-Deliverable Revenue Arrangements (“ASU 2009-13”) to account for revenue. Under this guidance the selling prices of deliverables under the arrangement may be derived using third-party evidence (“TPE”) or a best estimate of selling price (“BESP”), if vendor specific objective evidence (“VSOE”) is not available. The objective of BESP is to determine the price at which the Company would transact a sale if the element within the license agreement was sold on a standalone basis. Establishing BESP involves management’s judgment and considers multiple factors, including market conditions and company-specific factors including those factors contemplated in negotiating the agreements as well as internally developed models that include assumptions related to market opportunity, discounted cash flows, estimated development costs, probability of success, and the time needed to commercialize a product candidate pursuant to the license. In validating the Company’s BESP, the Company considers whether changes in key assumptions used to determine the BESP will have a significant effect on the allocation of the arrangement consideration between the multiple deliverables. Deliverables under the arrangement are separate units of accounting if (i) the delivered item has value to the customer on a standalone basis, and (ii) if the arrangement includes a general right of return relative to the delivered item, delivery or performance of the undelivered item is considered probable and substantially within the control of the Company. The arrangement consideration that is fixed or determinable at the inception of the arrangement is allocated to the separate units of accounting based on their relative selling prices. The appropriate revenue recognition model is applied to each element, and revenue is accordingly recognized as each element is delivered. The Company may exercise significant judgment in determining whether a deliverable is a separate unit of accounting. In determining the separate units of accounting, the Company evaluates whether the license has standalone value to the collaborator based on consideration of the relevant facts and circumstances for each arrangement. Factors considered in this determination include the research and development capabilities of the collaborator and the availability of relevant research expertise in the marketplace. In addition, the Company considers whether or not (i) the collaborator can use the license for its intended purpose without the receipt of the remaining deliverables, (ii) the value of the license is dependent on the undelivered items, and (iii) the collaborator or other vendors can provide the undelivered items. Under a collaborative research and license agreement, a steering committee is typically responsible for overseeing the general working relationships, determining the protocols to be followed in the research and development performed, and evaluating the results from the continued development of the product in order to determine the clinical studies to be performed. The Company evaluates whether its participation in joint research and development steering committees is a substantive obligation or whether the services are considered inconsequential or perfunctory. The Company’s participation on a steering committee is considered “participatory” and therefore accounted for as a separate element when the collaborator requires the participation of the Company to ensure all elements of an arrangement are maximized. Steering committee services that are considered participatory are combined with other research services or performance obligations required under an arrangement, if any, in determining the level of effort required in an arrangement and the period over which the Company expects to complete its aggregate performance obligations. Alternatively, the Company’s participation on a steering committee is considered “protective” and therefore not accounted for as a separate element in a case where the Company can exercise or control when to be involved at its own discretion. Factors the Company considers in determining if its participation in a joint steering committee is participating or protective include: (i) which party negotiated or requested the steering committee, (ii) how frequently the steering committee meets, (iii) whether or not there are any penalties or other recourse if the Company does not attend the steering committee meetings, (iv) which party has decision making authority on the steering committee, and (v) whether or not the collaborator has the requisite experience and expertise associated with the research and development of the licensed intellectual property. For agreements entered into prior to October 1, 2011, the Company accounted for the multiple elements within the agreements as a single unit of accounting and all payments received were recognized as revenue over the estimated period of performance of the entire arrangement as the Company was not able to separately recognize revenue for the elements under the provisions of previously applicable revenue recognition guidance. For all periods presented, whenever the Company determines that an element is delivered over a period of time, revenue is recognized using either a proportional performance model or a straight-line model over the period of performance, which is typically the research and development term. Full-time equivalents (“FTEs”) are typically used as the measure of performance. At each reporting period, the Company reassesses its cumulative measure of performance and makes appropriate adjustments, if necessary. The Company recognizes revenue using the proportional performance model whenever the Company can make reasonably reliable estimates of the level of effort required to complete its performance obligations under an arrangement. Revenue recognized under the proportional performance model at each reporting period is determined by multiplying the total expected payments under the contract (excluding royalties and payments contingent upon achievement of milestones) by the ratio of the level of effort incurred to date to the estimated total level of effort required to complete the performance obligations under the arrangement. Revenue is limited to the lesser of the cumulative amount of payments received or the cumulative amount of revenue earned, as determined using the proportional performance model as of each reporting period. Alternatively, if the Company cannot make reasonably reliable estimates the level of effort required to complete its performance obligations under an arrangement, then revenue under the arrangement is recognized on a straight-line basis over the period expected to complete the Company’s performance obligations. If and when a contingent milestone payment is earned, the additional consideration to be received is allocated to the separate units of accounting in the arrangement based on their relative selling prices at the inception of the arrangement. Revenue is limited to the lesser of the cumulative amount of payments received or the cumulative amount of revenue earned, as determined on a straight-line basis as of the period end date. If the Company cannot reasonably estimate when its performance obligation period ends, then revenue is deferred until the Company can reasonably estimate when the performance obligation period ends. Royalty revenue, if any, is recognized based on contractual terms when reported sales are reliably measurable and collectibility is reasonably assured, provided that there are no performance obligations then remaining. To date, none of the Company’s products have been approved, and therefore the Company has not earned any royalty revenue from product sales. During the three and six months ended March 31, 2013 and 2012 the Company also generated revenue from a government contract that reimburses the Company for certain allowable costs for the funded project. Revenue from the government contract is recognized when the related service is performed. The related costs incurred by the Company under the government contract are included in research and development expense in the statements of operations. Amounts received prior to satisfying all revenue recognition criteria are recorded as deferred revenue in the accompanying balance sheets. Amounts not expected to be recognized as revenue within the next twelve months of the balance sheet date are classified as long-term deferred revenue. In the event that a collaborative research and license agreement is terminated and the Company then has no further performance obligations, the Company recognizes as revenue any amounts that had not previously been recorded as revenue but were classified as deferred revenue at the date of such termination.
Recently Issued and Adopted Accounting Pronouncements	Recently Issued and Adopted Accounting Pronouncements In February 2013, the FASB issued ASU No. 2013-02, Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income (“ASU 2013-02”). This newly issued accounting standard requires an entity to provide information about the amounts reclassified out of accumulated other comprehensive income by component. In addition, an entity is required to present, either on the face of the statement where net income is presented or in the notes, significant amounts reclassified out of accumulated other comprehensive income by the respective line items of net income but only if the amount reclassified is required under U.S. GAAP to be reclassified to net income in its entirety in the same reporting period. For other amounts that are not required under U.S. GAAP to be reclassified in their entirety to net income, an entity is required to cross-reference to other disclosures required under U.S. GAAP that provide additional detail about those amounts. ASU 2013-02 is effective for fiscal years and interim periods within those years beginning after December 15, 2012 and will become effective for the Company on October 1, 2013. The Company does not believe the adoption of this standard will have an impact on the Company’s financial position or results of its operations. Other accounting standards that have been issued by the FASB or other standards-setting bodies that do not require adoption until a future date are not expected to have a material impact on the Company’s financial statements upon adoption.

- Definition

Disclosure of accounting policy for revenue recognition. If the entity has different policies for different types of revenue transactions, the policy for each material type of transaction is generally disclosed. If a sales transaction has multiple element arrangements (for example, delivery of multiple products, services or the rights to use assets) the disclosure may indicate the accounting policy for each unit of accounting as well as how units of accounting are determined and valued. The disclosure may encompass important judgment as to appropriateness of principles related to recognition of revenue. The disclosure also may indicate the entity's treatment of any unearned or deferred revenue that arises from the transaction.

+ References + Details

Fair Value of Financial Assets and Liabilities (Tables)

6 Months Ended

Mar. 31, 2013

Financial Assets and Liabilities That Were Subject to Fair Value Measurement on Recurring Basis


	Fair Value Measurements as of March 31, 2013 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents	$	72,016	$	—	$	—	$	72,016
Marketable securities		1,010		46,266		—		47,276

	$	73,026	$	46,266	$	—	$	119,292

Liabilities:
Warrant liability	$	—	$	—	$	1,767	$	1,767

	$	—	$	—	$	1,767	$	1,767


	Fair Value Measurements as of September 30, 2012 Using:
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents	$	6,471	$	—	$	—	$	6,471
Marketable securities		1,015		33,892		—		34,907

	$	7,486	$	33,892	$	—	$	41,378

Liabilities:
Warrant liability	$	—	$	—	$	2,001	$	2,001

	$	—	$	—	$	2,001	$	2,001

Rollforward of Aggregate Fair Values of Warrants


Balance, September 30, 2012	$	2,001
Warrants expired		(20	)
Decrease in fair value		(214	)

Balance, March 31, 2013	$	1,767

Marketable Securities (Tables)

6 Months Ended

Mar. 31, 2013

Fair Value of Available-for-Sale Marketable Securities by Type of Security

As of March 31, 2013 and September 30, 2012, the fair value of available-for-sale marketable securities by type of security was as follows:


	March 31, 2013
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Commercial paper	$	10,186	$	—	$	—		$	10,186
Corporate bonds		28,084		5		(14	)		28,075
U.S. Agency bonds		4,555		—		—			4,555
Certificate of deposit		3,450		—		—			3,450
U.S. Treasury notes		1,008		2		—			1,010

	$	47,283	$	7	$	(14	)	$	47,276


	September 30, 2012
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Commercial paper	$	8,143	$	—	$	—		$	8,143
Corporate bonds		25,741		9		(1	)		25,749
U.S. Treasury notes		1,013		2		—			1,015

	$	34,897	$	11	$	(1	)	$	34,907

- Definition

Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62557-112803

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27337-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27198-111563

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62586-112803

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27161-111563

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27357-111563

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27290-111563

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 19, 20, 21
-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 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS115-1/124-1
-Paragraph 17
-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 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 03-1
-Paragraph 21
-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.

+ Details

Accrued Expenses and Other Long-Term Liabilities (Tables)

6 Months Ended

Mar. 31, 2013

Accrued Expenses (Current) and Other Long-Term Liabilities

Accrued expenses (current) and other long-term liabilities consisted of the following as of March 31, 2013 and September 30, 2012:


	March 31, 2013		September 30, 2012

Accrued expenses:
Accrued payroll and related expenses	$	493	$	1,305
Accrued vendor manufacturing		23		1,330
Accrued professional fees		629		718
Accrued third-party license fees		728		222
Accrued other		592		291

	$	2,465	$	3,866

Other long-term liabilities:
Accrued rent expense	$	101	$	75
Present value of accrued third-party license fees		433		423

	$	534	$	498

Stock-Based Awards (Tables)

6 Months Ended

Mar. 31, 2013

Data Used to Determine Value of Stock Option Grants, Presented on Weighted Average Basis

The relevant data used to determine the value of the stock option grants is as follows, presented on a weighted average basis:


	Three Months Ended March 31,				Six Months Ended March 31,
	2013			2012	2013			2012

Risk-free interest rate		1.08	%	n/a		1.03	%	n/a
Expected term (in years)		6.16		n/a		6.10		n/a
Expected volatility		71	%	n/a		73	%	n/a
Expected dividend yield		0	%	n/a		0	%	n/a

Stock Option Activity

The following table summarizes stock option activity during the six months ended March 31, 2013:


	Shares Issuable Under Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
				(In years)
Outstanding as of September 30, 2012		1,771,471		$	2.08		4.1	$	19,911
Granted		350,682			14.03
Exercised		(427,590	)		0.97
Expired		(2,864	)		2.59

Outstanding as of March 31, 2013		1,691,699		$	4.84		5.3	$	22,609

Options vested and expected to vest as of March 31, 2013		1,679,722		$	4.77		5.3	$	22,559

Options exercisable as of March 31, 2013		1,232,478		$	2.08		3.7	$	19,870

Stock-Based Compensation Expense

The Company recorded stock-based compensation expense for the three and six months ended March 31, 2013 and 2012 in the following expense categories:


	Three Months Ended March 31,				Six Months Ended March 31,
	2013		2012		2013		2012

Research and development	$	85	$	13	$	179	$	29
General and administrative		172		18		359		57

	$	257	$	31	$	538	$	86

- Definition

Tabular disclosure of the allocation of equity-based compensation costs to a given line item on the balance sheet and income statement for the period. This may include the reporting line for the costs and the amount capitalized and expensed.

+ References + Details

Net Income (Loss) Per Share (Tables)

6 Months Ended

Mar. 31, 2013

Basic and Diluted Net Income (Loss) Per Share Attributable to Common Stockholders

Basic and diluted net income (loss) per share attributable to common stockholders was calculated as follows for the three and six months ended March 31, 2013 and 2012:


	Three Months Ended March 31,						Six Months Ended March 31,
	2013			2012			2013			2012

Basic net income (loss) per share attributable to common stockholders:
Numerator:
Net income (loss)	$	(3,749	)	$	32,111		$	18,208		$	28,952
Accretion of redeemable convertible preferred stock to redemption value		(1,244	)		(1,331	)		(2,526	)		(2,705	)
Net income attributable to participating securities		—			(28,152	)		(13,670	)		(24,071	)

Net income (loss) attributable to common stockholders	$	(4,993	)	$	2,628		$	2,012		$	2,176

Denominator:
Weighted average common shares outstanding—basic		2,192,470			1,088,251			1,669,578			1,053,912

Net income (loss) per share attributable to common stockholders—basic	$	(2.28	)	$	2.41		$	1.21		$	2.06


Diluted net income (loss) per share attributable to common stockholders:
Numerator:
Net income (loss)	$	(3,749	)	$	32,111		$	18,208		$	28,952
Accretion of redeemable convertible preferred stock to redemption value		(1,244	)		(1,331	)		(2,526	)		(2,705	)
Net income attributable to participating securities		—			(25,279	)		(12,329	)		(21,802	)

Net income (loss) attributable to common stockholders—diluted	$	(4,993	)	$	5,501		$	3,353		$	4,445

Denominator:
Weighted average common shares outstanding—basic		2,192,470			1,088,251			1,669,578			1,053,912
Dilutive effect of common stock equivalents		—			1,448,649			1,414,506			1,323,299

Weighted average common shares outstanding—diluted		2,192,470			2,536,900			3,084,084			2,377,211

Net income (loss) per share attributable to common stockholders—diluted	$	(2.28	)	$	2.17		$	1.09		$	1.87

Nature of the Business and Basis of Presentation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	6 Months Ended
	Mar. 26, 2013	Mar. 31, 2013
Class of Stock [Line Items]
Shares issued in initial public offering	4,600,000
Shares issued, price per share	$ 14.00
Net proceeds from initial public offering	$ 59,892	$ 59,892

Financial Assets and Liabilities That Were Subject to Fair Value Measurement on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2013	Sep. 30, 2012
Assets:
Cash equivalents	$ 72,016	$ 6,471
Marketable securities	47,276	34,907
Assets, Fair Value Disclosure, Total	119,292	41,378
Liabilities:
Warrant liability	1,767	2,001
Liabilities, Fair Value Disclosure, Total	1,767	2,001
Level 1
Assets:
Cash equivalents	72,016	6,471
Marketable securities	1,010	1,015
Assets, Fair Value Disclosure, Total	73,026	7,486
Liabilities:
Warrant liability
Liabilities, Fair Value Disclosure, Total
Level 2
Assets:
Cash equivalents
Marketable securities	46,266	33,892
Assets, Fair Value Disclosure, Total	46,266	33,892
Liabilities:
Warrant liability
Liabilities, Fair Value Disclosure, Total
Level 3
Assets:
Cash equivalents
Marketable securities
Assets, Fair Value Disclosure, Total
Liabilities:
Warrant liability	1,767	2,001
Liabilities, Fair Value Disclosure, Total	$ 1,767	$ 2,001

Fair Value of Financial Assets and Liabilities (Detail) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
	Mar. 31, 2013	Sep. 30, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Nonconvertible preferred stock, stated liquidation preference	$ 1.00
Payout percentage	100.00%
Series 1 Nonconvertible Preferred Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of warrants	$ 1,767	$ 1,981
Series E Redeemable Convertible Preferred Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of warrants		$ 20

- Definition

The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

+ References + Details

Rollforward of Aggregate Fair Values of Warrants (Detail) - Warrant $ in Thousands	6 Months Ended
	Mar. 31, 2013 USD ($)
Fair Value, Instruments Classified in Shareholders' Equity Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	$ 2,001
Warrants expired	(20)
Decrease in fair value	(214)
Ending Balance	$ 1,767

Fair Value of Available-for-Sale Marketable Securities by Type of Security (Detail) - USD ($) $ in Thousands	Mar. 31, 2013	Sep. 30, 2012
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 47,283	$ 34,897
Gross Unrealized Gains	7	11
Gross Unrealized Losses	(14)	(1)
Fair Value	47,276	34,907
Commercial Paper
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	10,186	8,143
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	10,186	8,143
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	28,084	25,741
Gross Unrealized Gains	5	9
Gross Unrealized Losses	(14)	(1)
Fair Value	28,075	25,749
U.S. Agency Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	4,555
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	4,555
Certificate of Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,450
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	3,450
U.S. Treasury Notes
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,008	1,013
Gross Unrealized Gains	2	2
Gross Unrealized Losses
Fair Value	$ 1,010	$ 1,015

Marketable Securities - Additional Information (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2013 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Marketable securities maturing within two years, aggregate fair value	$ 12,629
Short Term Marketable Securities
Schedule of Available-for-sale Securities [Line Items]
Maturity period of the marketable securities	Within one year
U.S. Agency Bonds and Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Maturity period of the marketable securities	Within two years

Accrued Expenses (Current) and Other Long-Term Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2013	Sep. 30, 2012
Accrued expenses:
Accrued payroll and related expenses	$ 493	$ 1,305
Accrued vendor manufacturing	23	1,330
Accrued professional fees	629	718
Accrued third-party license fees	728	222
Accrued other	592	291
Accrued expenses	2,465	3,866
Other long-term liabilities:
Accrued rent expense	101	75
Present value of accrued third-party license fees	433	423
Other long-term liabilities	$ 534	$ 498

Collaboration Agreements (Detail) $ in Thousands	1 Months Ended			3 Months Ended			6 Months Ended		12 Months Ended
Collaboration Agreements (Detail) $ in Thousands	Jan. 31, 2013 USD ($)	Feb. 16, 2012 USD ($)	Jun. 30, 2011 USD ($)	Mar. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Mar. 31, 2012 USD ($)	Mar. 31, 2013 USD ($)	Mar. 31, 2012 USD ($)	Sep. 30, 2011 USD ($) Renewals
Abb Vie
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Proceed received to fund research activities			$ 92,450
Revenue Recognition Milestone Method Revenue Recognized							$ 15,000	$ 0
Abb Vie \| Milestone Payments \| Phase 3 Clinical Trial
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Proceed received to fund research activities					$ 15,000
Abb Vie \| Regulatory Filing Milestones
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Expected proceed from milestone payment							40,000
Abb Vie \| Commercial Milestone Payments
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Expected proceed from milestone payment							155,000
Abb Vie \| Commercial Milestone Payments \| Additional Funding Agreement Terms
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Expected proceed from milestone payment							80,000
Novartis
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue Recognition Milestone Method Revenue Recognized				$ 465		$ 34,667	11,877	34,667
Novartis \| Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Expected proceed from milestone payment		$ 406,000
Novartis \| Phase 1 Clinical Trial
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Milestone payment received	$ 11,000
Novartis \| Research \| Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Expected proceed from milestone payment		1,800
Novartis \| Quality Assurance and Testing
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Expected Nonrefundable upfront fee and reimbursement expense		34,442
Novartis \| Phase 2a Clinical Trial
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Expected proceed from milestone payment		$ 15,000
National Institute of Allergy and Infectious Diseases ("NIAID")
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Awarded contract for development, Contract period									5 years
Awarded contract for development, number of extension option \| Renewals									6
Revenue from grants				$ 731		$ 1,898	$ 2,178	$ 2,639
National Institute of Allergy and Infectious Diseases ("NIAID") \| Initial Award
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Awarded contract for development, amount									$ 14,300
Awarded contract for development, Contract period									30 months
National Institute of Allergy and Infectious Diseases ("NIAID") \| Maximum
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Awarded contract for development, amount									$ 42,700
National Institute of Allergy and Infectious Diseases ("NIAID") \| Maximum \| Initial Award
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Awarded contract for development, amount									$ 42,700

Stockholders' Equity (Detail) $ / shares in Units, $ in Thousands	1 Months Ended			3 Months Ended		6 Months Ended
	Mar. 26, 2013 USD ($) $ / shares shares	Mar. 21, 2013 shares	Mar. 01, 2013	Mar. 31, 2013 USD ($) shares	Mar. 31, 2012 USD ($)	Mar. 31, 2013 USD ($) shares	Mar. 31, 2012 USD ($)	Sep. 30, 2012 USD ($) shares	Oct. 31, 2010 USD ($) shares
Class of Stock [Line Items]
Common stock, shares authorized				100,000,000		100,000,000		70,000,000
Reverse stock split ratio			0.232
Shares issued in initial public offering	4,600,000
Shares issued, price per share \| $ / shares	$ 14.00
Net proceeds from initial public offering \| $	$ 59,892					$ 59,892
Conversion of Redeemable Convertible Preferred Stock and Convertible Preferred Stock
Class of Stock [Line Items]
Shares of common stock issued upon conversion of preferred stock		11,656,875
Series E Preferred Stock
Class of Stock [Line Items]
Warrants outstanding								12,500
Warrants expired						12,500
Series 1 Nonconvertible Preferred Stock
Class of Stock [Line Items]
Number of shares issuable upon exercise of the warrants									1,999,989
Fair value of warrants \| $				$ 1,767		$ 1,767		$ 1,981	$ 1,280
Income (expense) from change in fair value of outstanding warrants \| $				$ 214	$ 0	$ 214	$ 0

Stock-Based Awards (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	6 Months Ended
Stock-Based Awards (Detail) - USD ($) $ in Thousands	Jan. 17, 2013	Mar. 31, 2013	Mar. 31, 2013	Jan. 03, 2013	Sep. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares issued		18,027,612	18,027,612		1,343,147
Shares of common stock		17,818,796	17,818,796		1,134,331
Options granted to executives			350,682
Aggregate of unrecognized stock-based compensation cost		$ 1,721	$ 1,721
Weighted average recognition period			2 years 9 months 18 days
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock reserved for issuance				185,614
1995 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted, vesting percentage			25.00%
Options granted, expiration period			10 years
Increase in shares of common stock reserved for issuance under the plan	232,018
Total number of shares of common stock issued under the plan	2,772,777
Number of shares transferred from 1995 Plan to the 2012 Plan	26,742
1995 Equity Incentive Plan \| Executives \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted, vesting period			1 year
1995 Equity Incentive Plan \| Executives \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted, vesting period			4 years
1995 Equity Incentive Plan \| Board of Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted, vesting period			2 years
2012 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares issued	348,355
Common stock additional shares issued	374,489
Percentage of outstanding shares of common stock	3.00%
Shares of common stock	2,088,167
2012 Equity Incentive Plan [Member] \| Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted to executives		167,052
Fair value of options at the grant date		$ 1,487
Stock based compensation, expenses		$ 5

Data Used to Determine Value of Stock Option Grants, Presented on Weighted Average Basis (Detail)	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Share Based Payment Award Stock Options Valuation Assumptions [Line Items]
Risk-free interest rate	1.08%		1.03%
Expected term (in years)	6 years 1 month 28 days		6 years 1 month 6 days
Expected volatility	71.00%		73.00%
Expected dividend yield	0.00%		0.00%

Stock Option Activity (Detail) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Mar. 31, 2013 USD ($) $ / shares shares	Sep. 30, 2012 USD ($) $ / shares shares
Shares Issuable Under Options
Outstanding as of beginning of period \| shares	1,771,471
Granted \| shares	350,682
Exercised \| shares	(427,590)
Expired \| shares	(2,864)
Outstanding as of end of period \| shares	1,691,699	1,771,471
Options vested and expected to vest as of end of period \| shares	1,679,722
Options exercisable as of end of period \| shares	1,232,478
Weighted Average Exercise Price
Outstanding as of beginning of period \| $ / shares	$ 2.08
Granted \| $ / shares	14.03
Exercised \| $ / shares	0.97
Expired \| $ / shares	2.59
Outstanding as of end of period \| $ / shares	4.84	$ 2.08
Options vested and expected to vest as of end of period \| $ / shares	4.77
Options exercisable as of end of period \| $ / shares	$ 2.08
Weighted Average Remaining Contractual Term (In years)
Outstanding as of end of period	5 years 3 months 18 days	4 years 1 month 6 days
Options vested and expected to vest as of end period	5 years 3 months 18 days
Options exercisable as of end of period	3 years 8 months 12 days
Aggregate Intrinsic Value
Outstanding as of beginning of period \| $	$ 19,911
Outstanding as of end of period \| $	22,609	$ 19,911
Options vested and expected to vest as of end of period \| $	22,559
Options exercisable as of end of period \| $	$ 19,870

Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 257	$ 31	$ 538	$ 86
Research and Development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	85	13	179	29
General and Administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 172	$ 18	$ 359	$ 57

Basic and Diluted Net Income (Loss) Per Share Attributable to Common Stockholders (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Basic net income (loss) per share attributable to common stockholders:
Net income (loss)	$ (3,749)	$ 32,111	$ 18,208	$ 28,952
Accretion of redeemable convertible preferred stock to redemption value	(1,244)	(1,331)	(2,526)	(2,705)
Net income attributable to participating securities		(28,152)	(13,670)	(24,071)
Net income (loss) attributable to common stockholders	$ (4,993)	$ 2,628	$ 2,012	$ 2,176
Weighted average common shares outstanding-basic	2,192,470	1,088,251	1,669,578	1,053,912
Net income (loss) per share attributable to common stockholders-basic	$ (2.28)	$ 2.41	$ 1.21	$ 2.06
Diluted net income (loss) per share attributable to common stockholders:
Net income (loss)	$ (3,749)	$ 32,111	$ 18,208	$ 28,952
Accretion of redeemable convertible preferred stock to redemption value	(1,244)	(1,331)	(2,526)	(2,705)
Net income attributable to participating securities		(25,279)	(12,329)	(21,802)
Net income (loss) attributable to common stockholders-diluted	$ (4,993)	$ 5,501	$ 3,353	$ 4,445
Weighted average common shares outstanding-basic	2,192,470	1,088,251	1,669,578	1,053,912
Dilutive effect of common stock equivalents		1,448,649	1,414,506	1,323,299
Weighted average common shares outstanding-diluted	2,192,470	2,536,900	3,084,084	2,377,211
Net income (loss) per share attributable to common stockholders-diluted	$ (2.28)	$ 2.17	$ 1.09	$ 1.87

Net Income (Loss) Per Share - Additional Information (Detail) - Stock Options - shares	3 Months Ended	6 Months Ended
	Mar. 31, 2013	Mar. 31, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from the computation of diluted net income per share	245,225
Diluted Net Loss Per Share
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from the computation of diluted net income per share	1,540,845
Diluted Net Income Per Share
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from the computation of diluted net income per share		126,489

- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
-URI http://asc.fasb.org/extlink&oid=6505113

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Diluted Earnings Per Share
-URI http://asc.fasb.org/extlink&oid=6510752

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Contingent Stock Agreement
-URI http://asc.fasb.org/extlink&oid=6508534

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 40
-Subparagraph c
-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 128
-Paragraph 13, 14
-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 Emerging Issues Task Force (EITF)
-Number 07-4
-Paragraph 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 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 171
-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.

+ Details

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012	Sep. 30, 2012
Contingencies And Commitments [Line Items]
Office lease expiration period			September 2018
Rent expense	$ 237	$ 237	$ 474	$ 474
Outstanding letter of credit	436		436
Restricted cash	436		436		$ 436
Maintenance fees			105
One-time fee			50
License agreement, recorded liability	661		661
Accrued Expenses
Contingencies And Commitments [Line Items]
License agreement, recorded liability	228		228
Other Long-Term Liabilities
Contingencies And Commitments [Line Items]
License agreement, recorded liability	433		433
Litigation and Contingencies Related to Use of Intellectual Property [Member]
Contingencies And Commitments [Line Items]
Loss contingency accrual	$ 500
Fiscal Year 2013 [Member]
Contingencies And Commitments [Line Items]
License expense			250
Fiscal Year 2014 [Member]
Contingencies And Commitments [Line Items]
License expense			250
Fiscal Year 2015 [Member]
Contingencies And Commitments [Line Items]
License expense			$ 200