Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (9,441,497)	$ (31,848,223)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	34,344	41,493
Stock-based compensation expense	772,079	951,104
Amortization of debt issuance costs	11,995	18,703
Loss on disposal of assets		2,240
Non-cash interest (income)/expense on investments	(16,416)	(306,760)
Issuance of common stock in consideration for rights granted under Aurigene collaboration agreement (see Note 4(b))		23,968,183
Changes in operating assets and liabilities:
Accounts receivable	359,516	191,651
Prepaid expenses and other assets	243,419	(336,364)
Accounts payable and accrued and other liabilities	49,919	(441,223)
Total adjustments	1,454,856	24,089,027
Net cash used in operating activities	(7,986,641)	(7,759,196)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of investments	(29,466,909)	(57,561,876)
Sale of investments	20,183,998	16,983,000
Purchases of property and equipment	(7,945)	(14,957)
Decrease in restricted cash		13,877
Net cash used by investing activities	(9,290,856)	(40,579,956)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock associated with offerings, net of issuance costs (see Note 9(a))		64,859,997
Proceeds from issuance of common stock under the Company's share-based compensation plans	69,622	128,628
Payments on Curis Royalty's debt	(1,191,135)	(929,339)
Net cash (used in)/provided by financing activities	(1,121,513)	64,059,286
NET (DECREASE)/INCREASE IN CASH AND CASH EQUIVALENTS	(18,399,010)	15,720,134
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	33,091,165	7,747,411
CASH AND CASH EQUIVALENTS, END OF PERIOD	$ 14,692,155	23,467,545
Non-cash items:
Unpaid and accrued equity issuance costs		$ (240,590)