Summary of Significant Accounting Policies (Tables)

12 Months Ended

Jun. 30, 2012

Summary of Significant Accounting Policies

Schedule of inventory

	June 30,
	2012		2011
Raw materials	$	129	$	480
Work in process		1,159		—
Total	$	1,288	$	480

Schedule of components of other accrued liabilities

	June 30,
	2012		2011
Accrued contract payments	$	1,773	$	684
Accrued clinical trial costs		865		1,068
Accrued professional services		677		652
Accrued employee benefits		351		277
Accrued public reporting charges		208		78
Other current accrued liabilities		715		546
Total	$	4,589	$	3,305

Schedule of assets that are required to be measured at fair value on a recurring basis

	Fair Value Measurements at June 30, 2012 Using
			Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
	Total		(Level 1)		(Level 2)		(Level 3)
Cash, cash equivalents and restricted cash	$	163,488	$	163,488	$	—	$	—
	$	163,488	$	163,488	$	—	$	—

	Fair Value Measurements at June 30, 2011 Using
			Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
	Total		(Level 1)		(Level 2)		(Level 3)
Cash, cash equivalents and restricted cash	$	194,774	$	194,774	$	—	$	—
	$	194,774	$	194,774	$	—	$	—

Schedule of estimated useful lives of property and equipment

Machinery and equipment	5 years
Computer hardware and software	3 years
Furniture and fixtures	5 years
Leasehold improvements	Shorter of remaining lease term or 7 years

Schedule of common stock equivalents, as calculated in accordance with the treasury-stock method

	June 30,
	2012		2011		2010
Options outstanding to purchase common stock		6,442		6,491		6,065
Common stock equivalents under treasury stock method		2,194		1,901		1,853

Schedule of weighted-average assumptions used to estimate the fair value of each stock option

	Year Ended June 30,
	2012			2011			2010
Dividend		None			None			None
Volatility		59.70	%		58.81	%		59.90	%
Risk-free interest rate		2.16	%		2.43	%		3.19	%
Expected life (years)		7.1			7.2			7.0

Summary of stock option activity

	Number of Stock Options			Weighted- Average Exercise Price		Weighted- Average Remaining Life in Yrs		Aggregate Intrinsic Value
Outstanding at June 30, 2011		6,491		$	6.70
Granted		1,657		$	14.89
Exercised		(1,432	)	$	4.88
Forfeited/Canceled		(274	)	$	12.16
Outstanding at June 30, 2012		6,442		$	8.98		6.87	$	50,001
Outstanding at June 30, 2012—vested or unvested and expected to vest		6,135		$	9.21		6.79	$	48,662
Exercisable at June 30, 2012		3,416		$	6.34		5.48	$	35,525

Summary of vested stock option activity

	Year Ended June 30,
	2012		2011		2010
Total fair value of shares vested	$	5,647	$	3,427	$	2,410
Total intrinsic value of options exercised		12,476		3,467		1,888
Cash received for exercise of stock options		6,988		2,719		3,462

Schedule of percentage of total revenue recognized from each significant customer

	Year Ended June 30,
Collaborative Partner:	2012			2011			2010
Amgen		30	%		41	%		32	%
Bayer HealthCare		15	%		17	%		15	%
Biogen Idec		2	%		1	%		13	%
Biotest		14	%		9	%		9	%
Novartis		16	%		7	%		—	%
Sanofi		23	%		23	%		28	%