90 Recent Sales of Unregistered Securities On October 9, 2018, upon the closing of the IPO, all convertible preferred shares then outstanding automatically converted into 12,385,154 shares of common stock, 500,000 redeemable convertible preferred stock warrants automatically converted into common stock warrants and 100,000 of such warrants were exercised immediately following the closing of the IPO. The 2017 convertible notes converted into 2,637,292 shares of common stock and the 2018 convertible notes converted into 4,295,677 shares of common stock at the closing of the IPO. The issuance of such common stock upon conversion of the redeemable convertible preferred stock and convertible notes and the issuance of such common stock warrants upon conversion of the redeemable convertible preferred stock warrants were exempt from the registration requirements of the Securities Act of 1933, as amended, pursuant to Section 3(a)(9) thereof, involving an exchange of securities exchanged by the issuer with its existing security holders exclusively where no commission or other remuneration is paid or given directly or indirectly for soliciting such exchange. The issuance of the common stock upon the cash exercise of 100,000 common stock warrants was exempt from the registration under the Securities Act of 1933, as amended, pursuant to Section 4(a)(2) thereof as a transaction by an issuer not involving a public offering. No underwriters were involved in the issuance of the shares of common stock or common stock warrants. From January 2017 through October 9, 2018, we issued to certain of our employees, consultants and directors, options to purchase an aggregate of 4,241,153 shares of our common stock at exercise prices per share ranging from $0.06 to $10.29. We deemed these issuances to be exempt from registration under the Securities Act either in reliance on Rule 701 of the Securities Act as sales and offers under compensatory benefit plans and contracts relating to compensation in compliance with Rule 701, or in reliance on Section 4(a)(2), as transactions by an issuer not involving a public offering. All recipients either received adequate information about our company or had access, through employment or other relationships, to such information. No underwriters were involved in the foregoing issuances of securities. We filed a registration statement on Form S-8 under the Securities Act on October 9, 2018 to register all of the shares of our common stock subject to outstanding options and all shares of our common stock otherwise issuable pursuant to our equity compensation plan. Use of Proceeds from Initial Public Offering On October 9, 2018, we closed our IPO, in which we sold and issued 9,000,000 shares of common stock at a price to the public of $10.00 per share. On November 6, 2018, we sold and issued an additional 400,000 shares of common stock at $10.00 per share to the underwriters of our IPO following the partial exercise of their over-allotment option. The offer and sale of all of the shares of our common stock in our IPO were registered under the Securities Act pursuant to a registration statement on Form S-1 (File No. 333-227237), which was declared effective by the SEC on October 3, 2018. Following the sale of the above shares, the offering terminated. Morgan Stanley, BofA Merrill Lynch and Barclays acted as joint book-running managers and Chardan acted as lead manager. We received aggregate gross proceeds from our IPO of $94.0 million, or aggregate net proceeds of $83.5 million, inclusive of the partial over-allotment option exercise, after deducting underwriting discounts and commissions and other offering costs. None of the underwriting discounts and commissions or offering expenses were incurred or paid, directly or indirectly, to (i) our directors or officers or their associates, (ii) persons owning 10% or more of our common stock or (iii) any of our affiliates. There has been no material change in our planned use of the net proceeds from our IPO as described in our final prospectus filed pursuant to Rule 424(b)(4) under the Securities Act with the SEC on October 5, 2018. Purchases of Equity Securities by the Issuer and Affiliated Purchases None.