Summary of Significant Accounting Policies (Details 2)	12 Months Ended
	Jun. 30, 2014 USD ($) item	Jun. 30, 2013 USD ($)	Jun. 30, 2012 USD ($)	Jun. 30, 2013 EUR (€)
Inventory
Raw materials	$ 437,000	$ 75,000
Work in process	2,513,000	628,000
Total	2,950,000	703,000
Raw materials inventory write-downs	661,000	810,000
Minimum supply period of raw materials that is not supported by firm, fixed orders and/or projections from collaborators considered to expense inventory	12 months
Rolling period of firm, fixed orders for conjugate that the company is required to manufacture	6 months
Rolling period of manufacturing projections for the quantity of conjugate the collaborator expects to need	12 months
Maximum period of firm, fixed orders and/or projections from collaborators considered for capitalizing inventory	12 months
Charges to research and development expense related to raw material inventory identified as excess	364,000	798,000	748,000
Charges to research and development expense to write-down certain raw material inventory to its net realizable value	0	0	38,000
Other Accrued Liabilities
Accrued contract payments	2,914,000	2,406,000
Accrued clinical trial costs	1,778,000	1,849,000
Accrued professional services	833,000	678,000
Accrued employee benefits	454,000	411,000
Accrued public reporting charges	183,000	179,000
Other current accrued liabilities	506,000	526,000
Total	6,668,000	6,049,000
Financial Instruments and Concentration of Credit Risk
Number of financial institutions in the U.S. in which cash and cash equivalents are primarily maintained	3
Marketable securities held by entity	0
Net gains (losses) on forward contracts	2,000	197,000	(173,000)
Notional amounts of outstanding forward contracts	$ 0	$ 57,000		€ 41,000