CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities
Net loss	$ (49,724,054)	$ (35,958,979)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	187,993	125,956
Stock-based compensation expense	5,680,353	3,384,800
Change in fair value of derivative liabilities	(2,370,193)	(1,073,198)
Change in fair value of contingent consideration	(10,411,686)	2,572,000
Non-cash interest expense	2,895,840	1,395,833
Debt exchange expense	818,541
Impairment of goodwill	16,902,466
Unrealized foreign currency loss	49,691
Changes in operating assets and liabilities:
Prepaid expenses and other assets	2,292,570	(3,383,820)
Accounts payable, accrued expenses and other liabilities	(1,210,916)	571,234
Net cash used in operating activities	(34,889,395)	(32,366,174)
Cash flows from investing activities
Purchase of property and equipment	(77,332)	(514,855)
Restricted cash		20,000
Acquisition of Shape Pharmaceuticals, net of cash acquired		(12,847,803)
Purchase of short-term investments	(24,410,694)	(66,295,197)
Sales and maturities of short-term investments	59,935,562	25,662,731
Net cash (used in) provided by investing activities	35,447,536	(53,975,124)
Cash flows from financing activities
Proceeds from exercise of stock options and warrants	31,201	201,128
Proceeds from convertible notes payable, net		44,146,830
Retirement of convertible notes payable	(825,001)
Proceeds from issuance of common stock, net	2,583,889
Net cash provided by financing activities	1,790,089	44,347,958
Effect of exchange rate changes on cash and cash equivalents	(118,985)	(69,031)
Net increase (decrease) in cash and cash equivalents	2,229,245	(42,062,371)
Cash and cash equivalents - beginning of period	13,073,137	55,135,508
Cash and cash equivalents - end of period	15,302,382	13,073,137
Noncash investing and financing activities
Conversion of convertible notes to common stock	2,080,292
Cash paid for interest	$ 3,500,000	$ 1,796,444