Net loss per share (Tables)

12 Months Ended

Dec. 31, 2021

Earnings Per Share [Abstract]

Schedule of Potentially Dilutive Securities Outstanding Excluded from Computations of Diluted Weighted-Average Shares Outstanding

The following potentially dilutive securities outstanding have been excluded from the computations of diluted weighted-average shares outstanding because such securities have an antidilutive impact due to losses reported (in common stock equivalent shares).

	As of December 31,
	2021		2020
Warrants issued to 2010/2012 convertible note    holders to purchase common stock		102,070		102,070
Options to purchase common stock		6,125,549		2,837,739
Outstanding restricted stock units		435,750		581,000
Warrants issued to underwriter to purchase common    stock		16,500		16,500
2018 PIPE warrants		513,617		513,617
Total		7,193,486		4,050,926