On September 1, 2022, the board of directors of Silverback Therapeutics, Inc. approved the termination of employment of Valerie Odegard, Ph.D., President and Chief Scientific Officer, effective as of September 2, 2022 (the “Transition Date”), to extend cash runway and to allow Dr. Odegard and to pursue other employment opportunities. Dr. Odegard and have each entered into a consulting agreement with Silverback as of the Transition Date pursuant to which each has agreed to provide, on an as-needed basis, not to exceed 20 hours per week unless mutually agreed, transition services and to advise, consult and support management team in connection with the closing of the potential merger of a wholly owned subsidiary of the Company with and into ARS Pharmaceuticals, Inc., a Delaware corporation (the “Merger”), winddown activities related thereto, the sale of legacy assets and other services from the Transition Date until the later of (a) the closing of the Merger and (b) November 30, 2022. As consideration for each of their consulting services, Dr. Odegard will be paid an hourly rate of $350 and all outstanding equity awards held by Dr. Odegard as of the Transition Date will continue to vest and will remain exercisable during the consulting period.

Effective as of the Transition Date, Russ Hawkinson has been appointed to serve as Silverback's principal financial officer. Mr. Hawkinson also serves as Silverback's Senior Vice President of Finance and principal accounting officer. The biographical information for Mr. Hawkinson appears below: Russ Hawkinson, age 63, has served as Senior Vice President of Finance since April 2020 and served as a finance consultant from May 2016 to March 2020.

From May 2015 to June 2018, Mr. Hawkinson served as Chief Financial Officer at OncoResponse, Inc. From April 2007 to June 2018, he served as Chief Financial Officer at Theraclone Sciences, Inc. Mr. Hawkinson holds a B.A. from the University of Washington and was a C.P.A. in the state of Washington for 17 years. There are no arrangements or understandings between Mr. Hawkinson and any other persons in connection with Mr. Hawkinson's appointment as Interim Chief Financial Officer and principal financial officer.