Commitments and Contingencies - Additional Information (Details)		6 Months Ended	9 Months Ended
	May 06, 2014 USD ($)	Jun. 30, 2015 patient	Sep. 30, 2016 USD ($) $ / shares shares	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)	Aug. 21, 2014 USD ($)	Jul. 17, 2014 USD ($)	Sep. 17, 2013 USD ($)
Commitments And Contingencies [Line Items]
Deposits for clinical trial services			$ 3,520,885		$ 4,176,280
Discretionary cash bonus			$ 0	$ 0
Options, Granted (in shares) | shares			1,937,750
Exercise option price (in USD per share) | $ / shares			$ 0.29
Lease monthly rent			$ 8,063
Operating lease rent expense			81,000	$ 75,000
Rent expense, monthly amount			8,554
Novella Clinical
Commitments And Contingencies [Line Items]
Number of patients | patient		414
Deposits for clinical trial services			$ 3,233,108
Termination notice period			60 days
ICON
Commitments And Contingencies [Line Items]
Deposits for clinical trial services			$ 308,224
Termination notice period			60 days
Estimated payments for services						$ 3,500,000	$ 2,300,000	$ 2,700,000
Service fee, amendments and aggregate	$ 170,004
JHU
Commitments And Contingencies [Line Items]
Period within effective date of License Agreement			30 days
PharmaCell B.V Agreement
Commitments And Contingencies [Line Items]
Written notice period for termination			90 days
Written notice period for early termination			30 days
Employment Agreement With Management
Commitments And Contingencies [Line Items]
Base salary			$ 1,300,000
Discretionary cash bonus			$ 450,000
Options, Granted (in shares) | shares			825,000
Exercise option price (in USD per share) | $ / shares			$ 0.33
Stock options, vesting period			4 years
Restricted shares issued by the company (in shares) | shares			285,000