Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expense and Other Current Liabilities (Detail) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Accrued Liabilities And Other Liabilities [Abstract]
Accrued professional services	$ 429,467	$ 552,619
Accrued payroll and employee benefits	1,183,130	1,257,191
Accrued interest	5,047	1,192
Lease obligation, current portion	259,449
Deferred rent, current portion		175,490
Accrued research and development	1,966,111	2,076,704
Deferred revenue	61,563	19,753
Total accrued expenses	$ 3,904,767	$ 4,082,949