11. STOCKHOLDERS’ EQUITY

Preferred Stock

We are authorized to issue 10,000,000 shares of preferred stock. As of December 31, 2020 and 2019, there were no issued and outstanding shares of preferred stock. Our board of directors is authorized to fix or alter the designation, powers, preferences and rights of the shares of each series of preferred shares, and the qualifications, limitations or restrictions of any wholly unissued shares, to establish from time to time the number of shares constituting any such series, and to increase or decrease the number of shares, if any.

Common Stock

Authorized Shares of Common Stock

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On May 18, 2018, we amended our Certificate of Incorporation (the “Charter Amendment”) to increase the number of authorized shares of common stock from 200,000,000 to 400,000,000 shares. This Charter Amendment was approved by our stockholders at the annual meeting held on May 16, 2018. The Charter Amendment became effective upon the filing with the Secretary of State of the State of Delaware on May 18, 2018.

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Common Stock Public Offering

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In the second quarter of 2018, we completed an underwritten public offering in which we sold 18,400,000 shares of our common stock pursuant to an effective registration statement at a price to the public of $3.90 per share. We received net proceeds of approximately $67.2 million after deducting underwriting discounts and commissions and offering expenses.

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Open Market Sales Agreement

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In August 2020, we entered into an Open Market Sale Agreement (Sales Agreement) with Jefferies LLC (Jefferies), as our sole sales agent, pursuant to which we may sell, from time to time, through Jefferies, shares of our

common stock having an aggregate offering price of up to $65.0 million. As of December 31, 2020, we have not yet sold any shares under the Sales Agreement.

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