Stockholders' Equity - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Jun. 13, 2017
Dr. Angelos Stergiou
Class of Stock [Line Items]
Cancellation of management fee	$ 100,000
Issuance of shares in cancellation of net compensation	28,246
MSK
Class of Stock [Line Items]
Issuance of common stock, shares	38,321
Milestone payment canceled	$ 200,000
Equilibria Collaboration Agreement
Class of Stock [Line Items]
Issuance of common stock, shares	30,094
Cancellation of management fee	$ 100,000
Bridge Financing
Class of Stock [Line Items]
Shares issued		1,865,261
Share issue price per share		$ 3.91