Commitments and Contingencies - Additional Information (Details)				1 Months Ended	3 Months Ended
	Mar. 11, 2016 shares	Jun. 30, 2015 patient	May. 06, 2014 USD ($)	May. 13, 2016 USD ($)	Mar. 31, 2016 USD ($) $ / shares shares	Mar. 31, 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					$ 3,762,878		$ 4,176,280
Discretionary cash bonus					$ 0	$ 0
Options, Granted (in shares) | shares	1,082,000				1,082,000
Exercise option price (in USD per share) | $ / shares					$ 0.33
Lease monthly rent					$ 8,063
Percentage of annual increase of monthly base rent					3.00%
Operating lease rent expense					$ 27,000	$ 25,000
Novella Clinical
Commitments And Contingencies [Line Items]
Number of patients | patient		414
Deposits for clinical trial services					$ 3,725,722
Termination notice period					60 days
ICON
Commitments And Contingencies [Line Items]
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
Subsequent Event
Commitments And Contingencies [Line Items]
Rent expense, monthly amount				$ 8,554