Convertible promissory notes	12 Months Ended
Dec. 31, 2020
Convertible promissory notes
Convertible promissory notes	7. Convertible promissory notes From January 2019 through July 2019, the Company issued $6.8 million of non-interest bearing convertible promissory notes to several existing Series A Preferred shareholders and new investors. The notes were to mature on February 2, 2020, if not converted or otherwise settled prior to maturity. Upon completion of a qualified equity financing event, as defined in the note agreement, the notes were to automatically convert into shares of the stock sold in such a qualified financing and at a price equal to 80% of the subscription price. In the event that the Company were to sell additional shares of Series A Preferred prior to a qualified financing event, the notes were to automatically convert into shares of Series A Preferred at a discount to the $9.00 per share subscription price. The discount was equal to 1% for each month that has lapsed from the initial note issuance date to the date in which the extended sale of Series A Preferred is consummated. In November 2019, the Company completed the sale of its Series A Preferred and the notes automatically converted into 821,657 shares of Series A Preferred. The effective conversion price of the notes was less than the fair value of the Series A Preferred and therefore, no beneficial conversion feature was recorded for the discount. The Company accounted for the conversion upon a qualified financing event as a bifurcated redemption feature as settlement under this feature would be in a variable number of shares and at a substantial discount. At issuance and over the term of the note, the Company determined the probability of settlement pursuant to the qualified financing event to be remote. As such, the estimated fair value of the redemption feature was de minimis.

Convertible promissory notes

12 Months Ended

Dec. 31, 2020

7. Convertible promissory notes

From January 2019 through July 2019, the Company issued $6.8 million of non-interest bearing convertible promissory notes to several existing Series A Preferred shareholders and new investors. The notes were to mature on February 2, 2020, if not converted or otherwise settled prior to maturity. Upon completion of a qualified equity financing event, as defined in the note agreement, the notes were to automatically convert into shares of the stock sold in such a qualified financing and at a price equal to 80% of the subscription price. In the event that the Company were to sell additional shares of Series A Preferred prior to a qualified financing event, the notes were to automatically convert into shares of Series A Preferred at a discount to the $9.00 per share subscription price. The discount was equal to 1% for each month that has lapsed from the initial note issuance date to the date in which the extended sale of Series A Preferred is consummated.

In November 2019, the Company completed the sale of its Series A Preferred and the notes automatically converted into 821,657 shares of Series A Preferred. The effective conversion price of the notes was less than the fair value of the Series A Preferred and therefore, no beneficial conversion feature was recorded for the discount.

The Company accounted for the conversion upon a qualified financing event as a bifurcated redemption feature as settlement under this feature would be in a variable number of shares and at a substantial discount. At issuance and over the term of the note, the Company determined the probability of settlement pursuant to the qualified financing event to be remote. As such, the estimated fair value of the redemption feature was de minimis.