Public Stock Offerings

12 Months Ended

Dec. 31, 2019

Reverse Stock Split and Initial Public Offering [Abstract]

Reverse Stock Split and Initial Public Offering

Public Stock Offerings

On June 25, 2018, the Company closed the Initial Public Offering ("IPO") of its common stock pursuant to a registration statement on Form S-1, as amended. The Company sold an aggregate of 6,555,000 shares of common stock under the registration statement at an IPO price of $15.00 per share, including 855,000 shares of common stock pursuant to the exercise of the underwriters’ option to purchase additional shares. Net proceeds from the IPO were $88.9 million after deducting underwriting discounts and commissions as well as other IPO expenses. Upon closing the IPO, all outstanding shares of the Company's Series A, B and C convertible preferred stock were converted into 11,837,073 shares of common stock.

On February 19, 2019, the Company completed a public offering of its common stock pursuant to a registration statement on Form S-1, as amended. The Company sold an aggregate of 5,996,775 shares of common stock at a price of $10.00 per share, including 116,775 shares of common stock pursuant to the exercise of the underwriters' option to purchase additional shares. Net proceeds from the public offering were $55.5 million after deducting underwriting discounts and commissions, as well as other public offering expenses.

On August 6, 2019, the Company filed a shelf registration statement on Form S-3 with the SEC, which covers the offering, issuance and sale by the Company of up to an aggregate of $250.0 million of its common stock, preferred stock, debt securities, warrants and/or units, (the "Shelf"). The Company simultaneously entered into a Sales Agreement with Jefferies LLC, as sales agent, to provide for the offering, issuance and sale by the Company of up to $50.0 million of its common stock from time to time in "at-the-market" offerings under the Shelf. The Shelf was declared effective by the SEC on August 21, 2019. In December 2019, the Company sold an aggregate of 204,427 shares of common stock under the Shelf for net proceeds of $1.7 million after deducting selling commissions as well as other public offering expenses.

Warrants

In 2014 the Company issued 19,931 warrants (the “2014 Warrants”) to certain investors. The 2014 Warrants allow each holder to purchase one share of common stock for $5.912. There have been 18,512 2014 Warrants exercised, and 1,419 warrants remain outstanding as of December 31, 2019.

As part of the Loan Agreement discussed in Note 6, "Long-term Debt", the Lenders received warrants concurrent with the borrowing. The warrants represent a right for the lender to purchase shares of the Company’s common stock at an initial exercise price of $11.169 per share. The Company issued 53,720 warrants (the "2018 Term A Warrants") upon the drawdown of the 2018 Term A Loan in February 2018, and the Company issued 40,292 warrants (the "2018 Term B Warrants") upon the drawdown of the 2018 Term B Loan in September 2018. There have been no exercises of Term A Warrants or Term B Warrants, and as such all 53,720 warrants and 40,292 warrants were outstanding as of December 31, 2019, respectively.

Because the warrants are a freestanding instrument, indexed to the Company's stock, they do not meet the criteria for equity classification. Therefore, the warrants are classified as liabilities and subject to remeasurement at each reporting period until they are exercised, expired, or otherwise settled.

The Company recognized a gain (loss) of $78,000, $351,000 and $263,000 upon the change in fair value of the warrants during the year ended December 31, 2019 related to the 2014 Warrants, the Term A Warrants and the Term B Warrants, respectively. The Company recognized a gain (loss) of $(56,000), $(108,000) and $360,000 upon the change in fair value of the warrants during the year ended December 31, 2018 related to the 2014 Warrants, the Term A Warrants and the Term B Warrants, respectively.

As of December 31, 2019, the following warrants were outstanding:

	Outstanding Warrants	Exercise Price per Warrant	Expiration Date
2014 Warrants	1,419	$5.912	August 2020
Term A Warrants	53,720	$11.169	February 2025
Term B Warrants	40,292	$11.169	September 2025
	95,431