150,000,000 authorized common shares, par value of $0.001, and 5,000,000 preferred shares, par value of $0.001.

On September 14, 2017 we and Lincoln Park Capital Fund, LLC, or LPC, entered into a share and unit purchase agreement, which was amended on March 12, 2020, or the Purchase Agreement, pursuant to which we have the right to sell to LPC up to $11.0 million in shares of our common stock, par value $0.001 per share, subject to certain limitations and conditions set forth in the Purchase Agreement. On May 22, 2018 we obtained the requisite stockholder authorization to sell shares of our common stock to LPC in excess of 20% of our outstanding shares of common stock (as of the date we entered into the Purchase Agreement) in order to be able to sell to LPC the full amount remaining under the Purchase Agreement.

Pursuant to the Purchase Agreement, LPC initially purchased 1,644 of our units, or the Units, at a purchase price of $608.00 per unit, with each Unit consisting of (a) one share of our common stock and (b) one warrant to purchase one-quarter of a share of common stock at an exercise price of $699.20 per share, or Warrant. Each Warrant became exercisable six months following the issuance date until the date that is five years and six months after the issuance date and is subject to customary adjustments. The Warrants were issued only as part of the Units in the initial purchase of $1.0 million and no warrants shall be issued in connection with any other purchases of common stock under the Purchase Agreement.

After the initial purchase, if our stock price is above $1.00, as often as every other business day over the 54-month term of the Purchase Agreement, and up to an aggregate amount of an additional $10.0 million (subject to certain limitations) of shares of common stock, we have the right, from time to time, in our sole discretion and subject to certain conditions to direct LPC to purchase up to 7,500 shares of common stock. The purchase price of shares of common stock pursuant to the Purchase Agreement will be based on prevailing market prices of common stock at the time of sales without any fixed discount, and we will control the timing and amount of any sales of common stock to LPC. As consideration for entering into the Purchase Agreement, we issued to LPC 617 shares of common stock in September 2017 and, in connection with the amendment of the Purchase Agreement in March 2020, we paid LPC $0.1 million as an expense reimbursement. The consideration of 617 shares of our common stock were fair valued based on the closing price of our common stock as at the transaction date and recognized as part of offering expenses.

During the three months ended March 31,2021, we offered and sold zero shares of our common stock pursuant to the Purchase Agreement with LPC. Since entering into the Purchase Agreement, from September 14, 2017 through March 31, 2021, we offered and sold an aggregate of 27,868 shares of our common stock, including the 1,644 shares that were part of the initial purchase of Units. These aggregate sales resulted in gross proceeds to us of approximately $4.4 million and offering expenses of $0.5 million. As of March 31, 2021, shares of our common stock having an aggregate value of approximately $6.6 million remained available for sale under this offering program.

On April 27, 2020 and April 28, 2020, we entered into subscription agreements with certain accredited investors pursuant to which we sold to the purchasers in a private placement approximately 280,782 units, or Units, each consisting of (i) one share of common stock, and (ii) a warrant to purchase 0.75 shares of common stock at an offering price of $6.60 per Unit, for aggregate gross proceeds of approximately $1.9 million. The placement agent received a cash commission on the gross proceeds from the sale of the Units and was issued a five (5) year warrant upon substantially similar terms as the investor warrants to purchase 25,270 shares of common stock at an initial exercise price of $7.59 per share. The net proceeds to us, after deducting placement agent expenses and commissions and offering expenses was approximately $1.6 million.

Each warrant is exercisable beginning on October 27, 2020, the six-month anniversary of the initial closing date of the offering, through April 27, 2025, which is the five-year anniversary of the initial closing date of the offering. The warrants issued pursuant to subscription agreements executed on April 27, 2020 are exercisable at a price per share of common stock of $7.24, subject to adjustment, and the warrants issued pursuant to subscription agreements executed on April 28, 2020 are exercisable at a price per share of common stock of $7.32, subject to adjustment. Additionally, subject to certain exceptions, if, after the initial exercise date, (i) the volume weighted average price of the common stock for each of 30 consecutive trading days, or the Measurement Period, which, Measurement Period commences on the closing date, exceeds 300% of the exercise price (subject to adjustments for stock splits, recapitalizations, stock dividends and similar transactions), (ii) the average daily trading volume for such Measurement Period exceeds $500,000 per trading day and (iii) certain other equity conditions are met, and subject to a beneficial ownership limitation, then we may call for cancellation of all or any portion of the warrants then outstanding.

Placement agent expenses and commissions and offering expenses have been charged against the gross proceeds.

On July 1, 2020, we completed a registered direct offering, pursuant to which we sold 731,707 shares of our common stock at a price of $8.20 per share.

The registered direct offering raised total gross proceeds of approximately $6.0 million, and after deducting approximately $0.7 million in placement agent fees and offering expenses, we received net proceeds of approximately $5.3 million.

The placement agent fees and offering expenses have been charged against the gross proceeds.

On August 6, 2020, we completed an underwritten public offering of our securities, or the Public Offering, pursuant to which we sold an aggregate of (a) 569,043 shares of our common stock, including 92,856 shares subject to the underwriter’s option to purchase additional shares, or the Shares, and (b) pre-funded warrants to purchase 142,857 shares of our common stock, or the Pre-Funded Warrants, to the underwriter. The Shares were sold at the public offering price of $10.50 per share. The Pre-Funded Warrants were sold at a public offering price of $10.499, which represents the per share public offering price for the Shares less a $0.001 per share exercise price for each such Pre-Funded Warrant.

The Pre-Funded Warrants are exercisable at any time after the date of issuance. A holder of Pre-Funded Warrants may not exercise the warrant if the holder, together with its affiliates, would beneficially own more than 9.99% of the number of shares of common stock outstanding immediately after giving effect to such exercise. A holder of Pre-Funded Warrants may increase or decrease this percentage, but not in excess of 19.99%, by providing at least 61 days’ prior notice to us.

The Public Offering raised total gross proceeds of approximately $7.5 million and after deducting approximately $0.7 million in underwriting discounts and commissions and offering expenses, we received net proceeds of approximately $6.8 million. The underwriting discounts and commissions and offering expenses have been charged against the gross proceeds.

On December 7, 2020, we completed an underwritten public offering of our securities, pursuant to which we sold an aggregate of 2,472,500 shares of our common stock, including 322,500 shares subject to the underwriter’s option to purchase additional shares, or the Shares. The Shares were sold at the public offering price of $7.00 per share.

We also issued a warrant to purchase 50,000 shares of common stock to the representative of the underwriters, the Representative’s Warrant, as a portion of the underwriting compensation payable in connection with this offering. The Representative’s Warrant will be exercisable beginning on May 31, 2021, with an exercise price of $8.75 per share and a term of five years. Under ASC 260, the fair value of the Representative’s Warrant of $0.3 million was charged against Additional Paid-In Capital.

The underwritten public offering raised total gross proceeds of approximately $17.3 million and after deducting approximately $1.5 million in underwriting discounts and commissions and offering expenses, we received net proceeds of approximately $15.8 million. The underwriting discounts and commissions and offering expenses have been charged against the gross proceeds.

During the three months ended March 31, 2021 and 2020, we did not issue any shares of common stock to satisfy stock option exercises and issued no shares of common stock to satisfy restricted stock unit settlements.

As of March 31, 2021, we had reserved, pursuant to the 2018 Equity Incentive Plan, or the 2018 Plan, 521,100 shares of common stock for issuance upon exercise of stock options by employees, directors, officers and consultants of ours, of which 452,455 were reserved for options currently outstanding, 53,250 for restricted stock units currently outstanding, and 15,395 were available for future equity grants.

Under the 2018 Plan, we may grant options to purchase common shares or restricted stock units to our employees, directors, officers and consultants. The exercise price of the options is determined by our board of directors, or Board, but will be at least equal to the fair value of the shares of common stock at the grant date. The options vest in accordance with terms as determined by our Board, typically over three to four years for options issued to employees and consultants, and over one to three years for members of our Board. The expiry date for each option is set by our Board with a maximum expiry date of ten years from the date of grant. In addition, the 2018 Plan allows for accelerated vesting of outstanding equity awards in the event of a change in control. The terms for accelerated vesting, in the event of a change in control, is determined at our discretion and defined under the employment agreements for our officers and certain of our employees.

As of March 31, 2021, we had reserved, pursuant to the 2017 Equity Incentive Plan, or the 2017 Plan, 13,156 shares of common stock for issuance upon exercise of stock options, currently outstanding, by employees, directors and officers of ours. Upon the effectiveness of our 2018 Plan, we ceased granting equity awards under our 2017 Plan.

Under the 2017 Plan, we granted options to purchase shares of common stock or restricted stock units to our employees, directors, officers and consultants. The exercise price of the options was determined by our board of directors but was at least equal to the fair value of the shares of common stock at the grant date. The options vest in accordance with terms as determined by our Board, typically over three to four years for options issued to employees and consultants, and over one to three years for members of our Board. The expiry date for each option was set by our Board with a maximum expiry date of ten years from the date of grant. In addition, the 2017 Plan allows for accelerated vesting of outstanding equity awards in the event of a change in control. The terms for accelerated vesting, in the event of a change in control, is determined at our discretion and defined under the employment agreements for our officers and certain of our employees.

As of March 31, 2021, we had reserved, pursuant to the 2010 Performance Incentive Plan, or the 2010 Plan, 462 shares of common stock for issuance upon exercise of stock options and settlement of restricted stock units by employees, directors, officers and consultants of ours, of which 231 were reserved for options currently outstanding and 231 were reserved for restricted stock units currently outstanding.

Under the 2010 Plan we granted options to purchase shares of common stock and restricted stock units to our employees, directors, officers and consultants. The exercise price of the options was determined by our board of directors and was at least equal to the fair value of the shares of common stock at the grant date. The options vest in accordance with terms as determined by our Board, typically over three to four years for options issued to employees and consultants, and over one to three years for members of our Board. The expiry date for each option is set by our Board with a maximum expiry date of ten years from the date of grant. In addition, the 2010 Plan allows for accelerated vesting of outstanding equity awards in the event of a change in control. The terms for accelerated vesting, in the event of a change in control, is determined at our discretion and defined under the employment agreements for our officers and certain of our employees.

We grant stock options that vest over time in accordance with terms as determined by our Board, which terms are typically four years for employee and consultant grants and one to three years for Board option grants. We also grant stock option awards that vest in conjunction with certain performance conditions to executive officers, employees and consultants. At each reporting date, we are required to evaluate whether achievement of the performance conditions is probable. Compensation expense is recorded over the appropriate service period based upon our assessment of accomplishing each performance condition. The expiry date for each option is set by our Board, which is typically seven to ten years. The exercise price of the options is determined by our Board.

Stock option transactions and the number of stock options outstanding are summarized below:

	Number of		Weighted
	Optioned		Average
	Common		Exercise
	Shares		Price
Balance, December 31, 2020		227,442	$	44.64
Granted		238,400		13.07
Balance, March 31, 2021		465,842	$	28.48

The fair value of each stock award for employees and directors is estimated on the grant date and for consultants at each reporting period, using the Black-Scholes option-pricing model based on the weighted-average assumptions noted in the following table:

	Three Months Ended
	March 31,
	2021			2020
Risk-free interest rates		0.59	%		1.51	%
Expected dividend yield		0	%		0	%
Expected life		6.01			6.02
Expected volatility		109.87	%		104.06	%

The expected life was calculated based on the simplified method as permitted by the SEC’s Staff Accounting Bulletin 110, Share-Based Payment. We consider the use of the simplified method appropriate because of the lack of sufficient historical exercise data following the Arrangement. The computation of expected volatility was based on the historical volatility of comparable companies from a representative peer group selected based on industry and market capitalization. The risk-free interest rate is based on a U.S. Treasury instrument whose term is consistent with the expected life of the stock options. In addition to the assumptions above, as required under ASC 718, management made an estimate of expected forfeitures and is recognizing compensation costs only for those equity awards expected to vest. Forfeiture rates are estimated using historical actual forfeiture rates. These rates are adjusted on a quarterly basis and any change in compensation expense is recognized in the period of the change. We have never paid or declared cash dividends on our common stock and do not expect to pay cash dividends in the foreseeable future.

The results for the periods set forth below included share-based compensation expense for stock options and restricted stock units in the following expense categories of the consolidated statements of loss (in thousands):

	Three Months Ended
	March 31,
	2021		2020
Research and development	$	172	$	86
General and administrative	$	370		216
Total stock-based compensation	$	542	$	302

As of March 31, 2021, the total unrecognized compensation expense related to stock options granted was $4.3 million, which is expected to be recognized as expense over a period of approximately 3.0 years from March 31, 2021.

For the three months ended March 31, 2021, a total of 1,778,596 shares, consisting of warrants to purchase 1,259,273 shares, options exercisable for 465,842 shares and 53,481 restricted stock units, have not been included in the loss per share computation, as their effect on diluted per share amounts would have been anti-dilutive. For the same period in 2020, a total of 1,480,774 shares underlying options, restricted stock units and warrants have not been included in the loss per share computation.

We grant restricted stock unit awards that generally vest and are expensed over a four-year period. We also grant restricted stock unit awards that vest in conjunction with certain performance conditions to certain executive officers, key employees and consultants. At each reporting date, we are required to evaluate whether achievement of the performance conditions is probable. Compensation expense is recorded over the appropriate service period based upon our assessment of accomplishing each performance condition. For the three months ended March 31, 2021, we recorded a compensation expense of $0.1 million related to these awards, compared to $30,000 for the three months ended March 31, 2020.

The following table summarizes our restricted stock unit award activity during the three months ended March 31, 2021:

			Weighted
	Number		Average
	of		Grant Date
	Shares		Fair Value
Balance, December 31, 2020		231	$	580.00
Granted		53,250		13.09
Balance, March 31, 2021		53,481	$	15.54

As of March 31, 2021, we had approximately $0.1 million in total unrecognized compensation expense related to our restricted stock unit awards that is to be recognized over a weighted-average period of approximately 2.12 years.

We recognize non-employee stock-based compensation expense over the period of expected service by the non-employee. As the service is performed, we are required to update our valuation assumptions, re-measure unvested options and restricted stock units and record the stock-based compensation using the valuation as of the vesting date. This differs from the accounting for employee awards where the fair value is determined at the grant date and is not subsequently adjusted. This re-measurement may result in higher or lower stock-based compensation expense in the Consolidated Statements of Loss and Comprehensive Loss. As such, changes in the market price of our stock could materially change the value of an option or restricted stock unit and the resulting stock-based compensation expense.

The following is a summary of outstanding warrants to purchase common stock at March 31, 2021:

	Total
	Outstanding		Exercise
	and		price per
	Exercisable		Share		Expiration Date
(1) Warrants issued in September 2017 financing		411	$	699.200	March 2023
(2) Warrants issued in June 2018 financing		114,100	$	80.000	June 2023
(3) Warrants issued in October 2018 financing		31,215	$	62.890	October 2023
(4) Warrants issued in May 2019 financing		60,000	$	90.000	May 2025
(5) Warrants issued in December 2019 financing		628,584	$	6.600	December 2024
(6) Warrants issued in April 2020 financing		182,461	$	7.240	April 2025
(7) Warrants issued in April 2020 financing		24,375	$	7.320	April 2025
(8) Warrants issued in April 2020 financing		25,270	$	7.590	April 2025
(9) Pre-Funded warrants issued in August 2020 financing		142,857	$	0.001	*
(10) Warrants issued in December 2020 financing		50,000	$	8.750	December 2025

*The pre-funded warrants do not have an expiration date.

For the three months ended March 31, 2021, warrants to purchase 31,467 shares, issued in the December 2019 financing, were exercised at a per unit price of $6.60, for proceeds of $0.2 million, and warrants to purchase 3,750 shares issued in the April 2020 financing were exercised for a per unit price of $7.32, for proceeds of $27,450. No warrants were exercised during the three months ended March 31, 2020. As of March 31, 2021, all of our outstanding warrants were classified as equity.