Note 7 - Stockholders' Equity

3 Months Ended

Mar. 31, 2023

Notes to Financial Statements

Equity [Text Block]

(7) Stockholders’ Equity

Warrants - Set forth below is a table of activity of warrants for common stock and the related weighted average exercise price per warrant.

	Number of		Weighted
	Common Stock		Average
	Warrants		Exercise Price
Balance as of December 31, 2022		2,424,724	$	6.36
Warrants for common stock sold		—		—
Warrants for common stock exercised		—		—
Balance as of March 31, 2023		2,424,724	$	6.36

Lincoln Park Capital stock purchase agreement - On March 29, 2021, we entered into a purchase agreement with Lincoln Park Capital Fund, LLC (Lincoln Park) (Purchase Agreement) and a registration rights agreement (Registration Rights Agreement), pursuant to which we have the right to sell to Lincoln Park shares of our common stock having an aggregate value of up to $20 million, subject to certain limitations and conditions in the Purchase Agreement.

Pursuant to the Purchase Agreement in March 2021, Lincoln Park purchased 373,832 shares of common stock, at a price of $5.35 per share, for a total gross purchase price of $2 million (Initial Purchase) and we issued 80,000 shares of common stock as commitment shares, which included 5,000 commitment shares issued on a pro rata basis for the initial $2 million purchase.

As of March 31, 2023, we had not sold any common stock to Lincoln Park under the Purchase Agreement other than the Initial Purchase.

Cantor Fitzgerald Sales agreement - On April 12, 2022, we entered into a sales agreement (Sales Agreement) with Cantor Fitzgerald & Co. (Cantor) as the sales agent, pursuant to which we may offer and sell, from time to time, through Cantor, shares of common stock having an aggregate offering price of up to $10.5 million (ATM Offering). We are not obligated to sell any common stock shares pursuant to the Sales Agreement. Under the terms of the Sales Agreement, we pay Cantor a commission of 3% of the aggregate proceeds from the sale of shares and reimburse certain legal fees. We filed a prospectus supplement under our existing registration statement covering the offer and sale of up to $10.5 million of common stock, of which approximately $8.5 million was still available for offer and sale as of March 31, 2023.

During the three months ended March 31, 2023, we sold 106,241 shares of common stock under the ATM Offering at then-market prices for total gross proceeds of $244,000, with net issuance costs of $13,000.