Annual report pursuant to Section 13 and 15(d)

Unaudited Quarterly Financial Information - Schedule of Quarterly Financial Information (Detail)

v3.10.0.1
Unaudited Quarterly Financial Information - Schedule of Quarterly Financial Information (Detail) - USD ($)
3 Months Ended 12 Months Ended
Dec. 31, 2018
Sep. 30, 2018
Jun. 30, 2018
Mar. 31, 2018
Dec. 31, 2017
Sep. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2018
Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]                    
Revenue $ 56,050 $ 228,000 $ 205,773 $ 25,000 $ 29,135 $ 250,000 $ 299,506 $ 575,368 $ 514,823 $ 1,154,009
Operating expenses 12,579,970 12,879,961 12,510,139 13,474,163 11,267,948 13,001,623 13,220,879 13,051,387 51,444,233 50,541,837
Net loss $ (12,453,003) $ (12,645,291) $ (12,298,371) $ (13,443,457) $ (11,236,477) $ (12,748,248) $ (12,919,010) $ (12,473,140) $ (50,840,122) $ (49,376,875)
Loss per share, basic and diluted $ (0.48) $ (0.49) $ (0.48) $ (0.55) $ (0.50) $ (0.58) $ (0.63) $ (0.61) $ (1.99) $ (2.31)