CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
Royalty income	$ 112,868	$ 124,804
Diagnostic service revenue	7,618	2,166
Total revenues	120,486	126,970
Costs and expenses:
Cost of revenue	309,271	176,425
Research and development	3,208,064	2,197,659
Selling and marketing	3,057,552	794,653
General and administrative	4,004,247	1,805,985
Total operating expenses	10,579,134	4,974,722
Loss from operations	(10,458,648)	(4,847,752)
Net interest expense	337,620	383,469
Gain (loss) from change in fair value of derivative instruments — warrants	533,750	(1,946,728)
Other income, net	0	3,568
Net loss	(10,262,518)	(7,174,381)
Preferred stock dividend	(6,060)	(6,060)
Net loss attributable to common stockholders	$ (10,268,578)	$ (7,180,441)
Net loss per common share - basic (in USD per share)	$ (0.35)	$ (0.33)
Net loss per common share - diluted (in USD per share)	$ (0.36)	$ (0.33)
Weighted average shares outstanding — basic	29,755,184	21,817,710
Weighted average shares outstanding — diluted	30,108,377	21,817,710