Equity Grants. Upon your Start Date, the Company shall grant to you a stock option (the “Option”) under the Company’s 2019 Equity Incentive Plan, as it may be amended from time to time (the “Plan”), to purchase 300,000 shares (subject to any adjustments for any stock splits, stock dividends, reverse stock splits or recapitalizations that are effected at any time during the period commencing after the date of this letter and ending on the grant date of the Option, the “Option Shares”) of the Company’s common stock, ​ par value per share (the “Common Stock”), at an exercise price equal to fair market value of the Common Stock, as determined by the Board of Directors of the Company, on the date of the grant of the Option (the “Grant Date”).

Equity Grants. UponGrant. Effective as of your Start Date, the Company shall grant towill issue you a stock option (the “Option”) under the Company’s 2019 Equity Incentive Plan, as it may be amended from time to time (the “Plan”),3,892,415 options to purchase 300,000a fixed number of shares (subject to any adjustments for any stock splits, stock dividends, reverse stock splits or recapitalizations that are effected at any time during the period commencing after the date of this letter and ending on the grant date of the Option, the “Option Shares”) of the Company’Company’s common stock, ​ par value per share (the “Common Stock”“Common Stock”), atrepresenting 4.0% of the total number of shares of the Company’s capital stock outstanding as of your Start Date, on an as-converted to Common Stock basis, including for purposes of this calculation the exercise of all options and warrants, including any shares issuable pursuant to existing option agreements or other instruments such as promissory notes, and the conversion of convertible securities outstanding as of the Start Date. This option grant will have an exercise price equal to the fair market value of the Common Stock, asStock on the Start Date (as determined by the Board or Compensation Committee) and, to the extent permitted under tax law, will be comprised of Directors of the Company, on the date of the grant of the Option (the “Grant Date”).incentive stock options under ​

Stock Option. At the first Board meeting following the Start Date, the Company shallwill grant to you a stockan option (the “Option”) under the Company’s 2019 Equity Incentive Plan, as it may be amended from time to time (the “Plan”), to purchase 300,4,000,000 shares (subjectof the Company’s common stock (the “Option”). The Option shall vest over a four-year period, with one quarter (1/4) of the shares subject to any adjustments for any stock splits, stock dividends, reverse stock splits or recapitalizations that are effected at any time during the period commencing afterOption vesting on the one year anniversary of the date of this lettergrant, and ending on the grant dateremaining shares vesting equally over the following thirty-six (36) months of continuous service. The Option shall be issued pursuant to the terms and conditions of the Option, the “Option Shares”) of the Company’Company’s common stock, ​ par value per share2015 Equity Incentive Plan (the “Common Stock”“Plan”), at an exercise price equal to 100% of the fair market value of the Common Stock, as determined by the Board of Directors of the Company,Company’s common stock on the date of grant, as provided in the Plan and consistent with the requirements for an exemption from the application of Section 409A of the Internal Revenue Code (the “Code”), and shall be governed in all respects by the terms of the Plan, the grant ofnotices and the Option (the “Grant Date”).option agreements.

If you decide to join us, it will be recommended at the first meeting of the Company’s Board of Directors following your Start Date,start date that the Company shall grantgrants you an incentive option to purchase 852,069 shares of the Company’s common stock (the “Option”). Subject to Company’s Board of Directors’ approval, you awill be granted such stock option (the “Option”) underin accordance with the Company’Company’s 20192011 Equity Incentive Plan, as it mayPlan (the “Plan”) and related option documents. You will be amended from timerequired to time (the “Plan”sign the applicable Stock Option agreement (“the Agreement”), and the options will be subject to purchase 300,000 shares (subject to any adjustments for any stock splits, stock dividends, reverse stock splits or recapitalizations that are effected at any time during the period commencing after the date of this letterterms and ending on the grant dateconditions of the Option,Plan and the “Option Shares”) ofAgreement. The exercise price per share will be equal to the Company’s common stock, ​ parfair market value per share (the “Common Stock”), at an exercise price equal to fair market value ofon the Common Stock,date the Option is granted, as determined by the Company’s Board of DirectorsDirectors. Twenty-five (25%) of the Company, onshares subject to the dateOption shall vest upon completion of a twelve month employment at the Company and the remaining shares subject to the Option shall vest in equal monthly installments over the next thirty-six months subject to your continued service with the Company through each vesting date, as described in the applicable option agreement. No right to any equity is earned or accrued until such time that vesting occurs, nor does the grant of the Option (the “Grant Date”).confer any right to continued vesting or employment.