Stock-based awards include stock options and restricted stock units under the 2012 Equity Incentive Plan, as amended (“2012 Plan”), and Inducement Awards, performance-based restricted stock units under an Incentive Award Performance-Based Restricted Stock Unit Agreement, and rights to purchase stock under the ESPP. The Company calculates the grant date fair value of all stock-based awards in determining the stock-based compensation expense.

Stock-based compensation expense for all stock-based awards consists of the following (in thousands):

	Three Months Ended		Three Months Ended		Nine Months Ended		Nine Months Ended
	December 31, 2020		December 31, 2019		December 31, 2020		December 31, 2019
Research and development	$	45	$	66	$	51	$	240
General and administrative	$	161	$	1,186	$	5,218	$	3,468
Total	$	206	$	1,252	$	5,269	$	3,708

The total unrecognized compensation cost related to unvested stock option grants as of December 31, 2020 was approximately $2,442,000 and the weighted average period over which these grants are expected to vest is 3.24 years.

The total unrecognized compensation cost related to unvested restricted stock units (not including performance-based restricted stock units) as of December 31, 2020 was approximately $30,000, which will be recognized over a weighted average period of 1.95 years.

The total unrecognized compensation cost related to unvested performance-based restricted stock units as of December 31, 2020 was approximately $30,000, which will be recognized over a weighted average period of 0.5 years.

As of December 31, 2020, there are no participants enrolled in the employee stock purchase plan for the current purchase period, beginning September 1, 2020.

The Company uses the Black-Scholes valuation model to calculate the fair value of stock options. Stock-based compensation expense is recognized over the vesting period using the straight-line method. The fair value of stock options was estimated at the grant date using the following weighted average assumptions:

	Three Months Ended			Three Months Ended			Nine Months Ended			Nine Months Ended
	December 31, 2020			December 31, 2019*			December 31, 2020			December 31, 2019
Dividend yield		—			—			—			—
Volatility		108.74	%		0.00	%		108.41	%		84.36	%
Risk-free interest rate		0.33	%		0.00	%		0.27	%		1.53	%
Expected life of options	6.00 years				—		6.00 years			6.00 years
Weighted average grant date fair value	$	6.09		$	—		$	6.21		$	4.60

The assumed dividend yield is based on the Company’s expectation of not paying dividends in the foreseeable future. The Company uses the Company-specific historical volatility rate as the indicator of expected volatility. The risk-free interest rate assumption was based on U.S. Treasury rates. The weighted average expected life of options was estimated using the average of the contractual term and the weighted average vesting term of the options. The measurement and classification of share-based payments to non-employees is consistent with the measurement and classification of share-based payments to employees.

The fair value of each restricted stock unit and performance-based restricted stock unit is recognized as stock-based compensation expense over the vesting term of the award. The fair value is based on the closing stock price on the date of the grant.

The Company uses the Black-Scholes valuation model to calculate the fair value of shares issued pursuant to the ESPP. Stock-based compensation expense is recognized over the purchase period using the straight-line method. The fair value of ESPP shares was estimated at the purchase period commencement date using the following assumptions:

	Three Months Ended			Three Months Ended			Nine Months Ended			Nine Months Ended
	December 31, 2020*			December 31, 2019*			December 31, 2020*			December 31, 2019
Dividend yield		—			—			—			—
Volatility		0.00	%		0.00	%		0.00	%		43.69	%
Risk-free interest rate		0.00	%		0.00	%		0.00	%		2.52	%
Expected term		—			—			—		6 months
Grant date fair value	$	—		$	—		$	—		$	0.29

*There were no participants in the ESPP for the purchase periods beginning September 1, 2019, March 1, 2020 and the current purchase period (beginning September 1, 2020).

The assumed dividend yield was based on the Company’s expectation of not paying dividends in the foreseeable future. The Company uses the Company-specific historical volatility rate as the indicator of expected volatility. The risk-free interest rate assumption was based on U.S. Treasury rates. The expected life is the 6-month purchase period.

The Company is authorized to issue 25,000,000 shares of preferred stock. There are no shares of preferred stock currently outstanding, and the Company has no current plans to issue shares of preferred stock.

On June 25, 2019, the Company received a notice letter from the Listing Qualifications Staff of the Nasdaq Stock Market LLC (“Nasdaq”) indicating that, based upon the closing bid price of the Company’s common stock for the last 30 consecutive business days, the Company no longer met the requirement to maintain a minimum closing bid price of $1 per share, as set forth in Nasdaq Listing Rule 5450(a)(1). On December 26, 2019, the Company obtained an additional compliance period of 180 calendar days by electing to transfer to The Nasdaq Capital Market. On March 26, 2020, the Company obtained shareholder approval to effect a reverse stock split in a range from 20:1 to 40:1 in order to meet the minimum closing bid price per share requirement under the Nasdaq Listing Rules.

On April 17, 2020, the Company received an additional notice letter from Nasdaq indicating that based on extraordinary market conditions, Nasdaq has determined to toll the compliance periods for bid price and market value of publicly held shares requirements (collectively, the “Price-based Requirements”) through June 30, 2020. Accordingly, since the Company had 66 calendar days remaining in its compliance period as of April 16, 2020, the Company had until September 4, 2020 to regain compliance. On August 18, 2020, the Company effected the Reverse Stock Split with a ratio of 20:1, and on September 2, 2020, the Company received notification from Nasdaq that the closing bid price of its common stock had been at $1.00 per share or greater for ten consecutive business days and that Nasdaq had closed the matter. There can be no assurance that the Company will be able to maintain compliance with the Price-based Requirements or other listing requirements necessary to maintain the listing of its common stock on the Nasdaq Capital Market.

The Company previously had an effective shelf registration statement on Form S-3 (File No. 333-222929) and the related prospectus previously declared effective by the Securities and Exchange Commission (the “SEC”) on February 22, 2018 (the “2018 Shelf”), that was set to expire on February 22, 2021, which registered $100,000,000 of common stock, preferred stock, warrants and units, or any combination of the foregoing. On January 19, 2021, the Company filed a shelf registration statement on Form S-3 (File No. 333-252224) and related prospectus. The shelf registration statement was declared effective by the SEC on January 29, 2021 (the “2021 Shelf”). The 2021 Shelf registered $150,000,000 of common stock, preferred stock, debt securities, warrants and units, or any combination of the foregoing. The 2021 Shelf replaced the 2018 Shelf on January 29, 2021.

On March 16, 2018, the Company entered into a Sales Agreement (“2018 Sales Agreement”) with H.C. Wainwright & Co., LLC and Jones Trading Institutional Services LLC (each an “Agent” and together, the “Agents”) and filed a prospectus supplement to the 2018 Shelf, pursuant to which the Company could offer and sell, from time to time through the Agents, shares of its common stock in at-the-market sales transactions having an aggregate offering price of up to $50,000,000. On January 29, 2021, the Company filed a prospectus to the 2021 Shelf, pursuant to which the Company may offer and sell, from time to time through the Agents, shares of its common stock in at-the-market sales transactions having an aggregate offering price of up to $50,000,000. Any shares offered and sold will be issued pursuant to the Company’s 2021 Shelf. $

During the three and nine months ended December 31, 2020, the Company issued 379,655 shares of common stock for net proceeds of $3.0 million in at-the-market offerings under the 2018 Sales Agreement. During the three and nine months ended December 31, 2019, the Company issued 0 and 304,369 shares of common stock, respectively, for net proceeds of $0 and $5.0 million, respectively, in at-the-market offerings under the 2018 Sales Agreement.

As of December 31, 2020, the Company has sold an aggregate of 1,265,614 shares of common stock in at-the-market offerings under the 2018 Sales Agreement, with gross proceeds of approximately $22.0 million. Under the 2021 Shelf, the Company can raise up to an aggregate of $150.0 million in future offerings, which includes $50.0 million available for future issuance through its at-the-market program under the 2018 Sales Agreement.

During the three and nine months ended December 31, 2020, the Company issued 5,200 and 7,800 shares of common stock upon the exercise of stock options, respectively. No stock option exercises occurred during the three and nine months ended December 31, 2019.

The following table summarizes the Company’s restricted stock units (not including performance-based restricted stock units) activity from March 31, 2020 through December 31, 2020:

	Number of Shares			Weighted Average Price
Unvested at March 31, 2020		18,116		$	43.49
Granted		—		$	—
Vested		(16,579	)	$	45.56
Cancelled / forfeited		—		$	—
Unvested at December 31, 2020		1,537		$	21.15

Performance-based restricted stock units

On April 24, 2017, the Company issued a Performance-Based Restricted Stock Unit Award for 10,441 shares of common stock (the “PBRSU”) to its then-newly hired Chief Executive Officer. The PBRSU was issued outside of the 2012 Plan, pursuant to an inducement award agreement, as an “inducement award” within the meaning of Nasdaq Marketplace Rule 5635(c)(4). While outside the Company’s 2012 Plan, the terms and conditions of the awards are consistent with awards granted to the Company’s executive officers pursuant to the 2012 Plan. On August 23, 2017, the Board formally approved the vesting criteria for the PBRSU. The vesting of the PBRSU is divided into five separate tranches each with independent vesting criteria. The first four tranches had performance criteria related to annual revenue goals with measurement at the end of fiscal year 2018 (20 percent), fiscal year 2019 (20 percent), fiscal year 2020 (20 percent), and fiscal year 2021 (20 percent). The fifth tranche had a performance metric related to a path to profitability goal measured as Negative Adjusted Earnings Before Interest, Taxes, Depreciation and Amortization (“EBITDA”) achievable at any point between the grant date and the end of fiscal year 2020 (20 percent). The number of units that ultimately vest for each tranche will range from 0 percent to 120 percent of the target amount, not to exceed 10,441 in aggregate. On December 12, 2018, the Board formally approved an amendment to the vesting criteria for the PBRSUs. As of December 12, 2018, 100 percent of the Negative Adjusted EBITDA tranche, or 2,088 shares had vested and 418 units had been forfeited. Based on the amendment to the vesting criteria, the remaining 7,935 units eligible to vest upon future performance were divided into three separate but equal tranches with independent vesting criteria based on the achievement of certain regulatory milestones.

Based on the amended PBRSU vesting terms, a Type III modification, the modified grant date fair value of the PBRSUs is $165,000 of which one-third is being recognized over the expected service period of each tranche ending on April 23, 2023. The Company began recording stock-based compensation expense for the initial performance tranches after the August 23, 2017 grant date when the initial financial performance goals were established and approved and has modified its recording of compensation expense in accordance with the amended performance tranches beginning on December 12, 2018. On September 15, 2020, vesting of all tranches accelerated due to a change in control.

On July 2, 2019, the Company issued Performance-Based Restricted Stock Unit Awards (the “PBRSU Retention Awards”) for an aggregate of 301,391 shares of common stock to its management team. The PBRSUs were issued pursuant to the 2012 Plan. The PBRSU Retention Awards vest in full upon the earlier of: (i) the Company’s engagement in a pre-IND meeting with the FDA, (ii) twenty-four months from the grant date, or (iii) a change in control. As of December 31, 2020, 111,682 shares were forfeited due to terminations and vesting for 177,480 shares accelerated due to a change in control. The remaining 12,229 shares are expected to vest twenty-four months from the grant date as these particular shares require two of the conditions to be met in order to vest.

The following table summarizes the Company’s performance-based restricted stock unit activity from March 31, 2020 through December 31, 2020:

	Number of Shares			Weighted Average Price
Unvested at March 31, 2020		197,644		$	10.24
Granted		—		$	—
Vested		(185,415	)	$	10.27
Cancelled / forfeited		—		$	—
Unvested at December 31, 2020		12,229		$	9.80

The following table summarizes the Company’s stock option activity from March 31, 2020 to December 31, 2020:

	Options Outstanding			Weighted Average Exercise Price		Aggregate Intrinsic Value
Outstanding at March 31, 2020		377,980		$	41.81	$	37,440
Options granted		501,875		$	7.59	$	—
Options cancelled / forfeited		(108,150	)	$	18.01	$	—
Options exercised		(7,800	)	$	5.32	$	22,464
Outstanding at December 31, 2020		763,905		$	23.07	$	2,022,138
Vested and Exercisable at December 31, 2020		349,115		$	41.47	$	67,966

The weighted average remaining contractual term of options exercisable and outstanding at December 31, 2020 was approximately 1.09 years.

In June 2016, the Board adopted, and in August 2016, the Company’s stockholders subsequently approved, the ESPP. The Company reserved 75,000 shares of common stock for issuance thereunder. The ESPP permits employees after five months of service to purchase common stock through payroll deductions, limited to 15 percent of each employee’s compensation up to $25,000 per employee per year or 500 shares per employee per six-month purchase period. Shares under the ESPP are purchased at 85 percent of the fair market value at the lower of (i) the closing price on the first trading day of the six-month purchase period or (ii) the closing price on the last trading day of the six-month purchase period. The initial offering period commenced in September 2016. At December 31, 2020, there were 59,435 shares available for purchase under the ESPP.

Common stock reserved for future issuance consisted of the following at December 31, 2020:

Common stock options outstanding and reserved under the 2012 Plan			659,495
Common stock reserved under the 2012 Plan			324,176
Common stock reserved under the ESPP			59,435
Restricted stock units outstanding under the 2012 Plan			1,537
Performance-based restricted stock units outstanding under the 2012 Plan			12,229
Common stock options outstanding and reserved under the Inducement Award Agreement			104,410
Total at December 31, 2020			1,161,282

Repurchased shares of common stock are recorded as treasury stock, at cost, but may from time to time be retired. Following the Reverse Stock Split in August 2020, the Company purchased 46 shares of treasury stock at cost of less than $0.1 million related to the funding of cash payments in lieu of the issuance of fractional shares.