Prepaid Expenses and Other Current Assets - Prepaid Expenses and Other Current Assets (Detail) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid manufacturing costs	$ 3,268,032	$ 1,526,013
Prepaid insurance	247,610	1,263,129
Prepaid subscriptions fees	561,430	501,251
Prepaid research fees	472,093	481,057
Prepaid commercialization expenses	168,611	62,959
Due from collaborative arrangements	306,678
Other	589,598	516,665
Total prepaid expenses and other current assets	$ 5,614,052	$ 4,351,074