1.

Position: You will serve as the President and Chief Executive Officer of La Jolla, and you will report to La Jolla's Board of Directors (the "Board").

2.

Base Salary: Your annualized base salary will be $500,000 ("Base Salary"). An amount equal to 1/24th of the Base Salary will be paid to you twice per month in accordance with La Jolla's standard payroll procedures and subject to standard payroll deductions and withholdings. Your Base Salary will be subject to annual review as determined by La Jolla's Board.

3.

Bonus:

a.

Target Bonus. With respect to each calendar year during your employment, in addition to your Base Salary, you will be eligible to earn an annual cash performance bonus, with the target bonus amount being equal to 55% of your Base Salary in effect at such time (the "Target Bonus"). It is understood and agreed that the Target Bonus is discretionary, and the actual bonus will be determined by the Board's assessment of La Jolla's achievement of the corporate goals for the second half of 2020. The payment of your Target Bonus is conditioned upon your continued employment with La Jolla through the date of payment.

b.

XERAVA Sales Threshold Bonuses. You are eligible to receive cash bonuses of up to $200,000 comprised of: (1) $31,000 if XERAVA annual U.S. net sales are at least $20 million during the calendar year ending December 31, 2021; (2) $56,000 if XERAVA annual U.S. net sales are at least $35 million in any calendar year ending on or before December 31, 2024; and (3) $113,000 if XERAVA annual U.S. net sales are at least $55 million in any calendar year ending on or before December 31, 2024 (collectively, the "XERAVA Sales Threshold Bonus"). XERAVA Sales Threshold Bonuses are subject to the terms and conditions provided in the Operating Agreement of La Jolla Pharmaceutical Holdings, LLC, a subsidiary of La Jolla.

4.

Equity Incentive Award: As of the Effective Date, you will be granted options to purchase 400,000 shares of La Jolla common stock ("Stock Options"). The exercise price of the Stock Options will be equal to the closing price of La Jolla's common stock on the Effective Date. The Stock Options will vest as follows:

a.

300,000 of the Stock Options will be subject to standard 4-year vesting (i.e., 25% vests on the first anniversary of the grant date, and the remaining 75% vests ratably on a monthly basis over the following three years); and

b.

100,000 of the Stock Options will vest as of December 31, 2021 if La Jolla's Adjusted Net Income for the year ending December 31, 2021 is greater than $15 million. Adjusted Net Income is equal to La Jolla's consolidated net income per General Accepted Accounting Principles in the U.S. excluding share-based compensation, depreciation and amortization expense, and accounts for the Healthcare Royalty Partners royalty and the facility rent on a cash basis.

5.

Benefits: You will be entitled during the term of your employment to participate in La Jolla's benefits programs, which are summarized in the attached 2020 Benefits Information Guide.

6.

Confidentiality Policy: You will be required to sign and abide by La Jolla's Confidential Information Agreement and La Jolla's Inventions and Assignment Agreement, and to comply with all La Jolla's policies and practices regarding the protection of its confidential information.

7.

At-will Employment: You should be aware that your employment with La Jolla is for no specified period and constitutes "at-will" employment. As a result, you are free to terminate your employment at any time, for any reason or for no reason. Similarly, La Jolla is free to terminate your employment at any time, for any reason or for no reason, provided, however that:

a.

If La Jolla terminates your employment without Cause, or you terminate your employment for Good Reason (as those terms are defined in Attachment A) on or before July 28, 2021, then: (1) you will receive as severance pay an amount equal to twelve (12) months of your then-current base salary (subject to all applicable federal, state and local tax withholdings, and payable over a twelve-month period in accordance with La Jolla's regular payroll practices); and (2) La Jolla will pay your COBRA premiums for medical, dental and vision insurance for you, your spouse and covered dependents, provided that you are eligible for and elect COBRA coverage, until the earlier of: (i) twelve (12) months after your employment ends; or (ii) the date that you become employed by a new employer.

b.

If La Jolla terminates your employment without Cause, or you terminate your employment for Good Reason within 12 months after a Change In Control Event (as defined in Attachment A) and such Change in Control Event occurs on or before July 28, 2021, then: (1) you will receive as severance pay an amount equal to eighteen (18) months of your then­ current base salary (subject to all applicable federal, state and local tax withholdings, and payable over a eighteen-month period in accordance with La Jolla's regular payroll practices); (2) you will receive 100% of your then­ current annual Target Bonus (subject to all applicable federal, state and local taxes and withholdings and payable in a lump sum); and (3) La Jolla will pay your COBRA premiums for medical, dental and vision insurance for you, your spouse and covered dependents, provided that you are eligible for and elect COBRA coverage, until the

earlier of: (i) eighteen (18) months after your employment ends; or (ii) the date that you become employed by a new employer.

8.

Entire Agreement: This offer letter constitutes the entire agreement between you and La Jolla relating to your employment, and supersedes all prior or contemporaneous understandings, negotiations and representations, whether oral or written, express or implied and supersedes all prior employment agreements with Tetraphase Pharmaceuticals, Inc.

/s/    Kevin Tang

Kevin Tang

Chairman of the Board

ACCEPTED:

/s/    Larry Edwards

July 28, 2020

Larry Edwards

Date