Exhibit 10.1
Going beyond every day.™
September 6, 2023
Howard Horn
Re: Amendment No. 1 to Offer Letter
Dear Howard:
On behalf of Ultragenyx Pharmaceutical Inc. (“Ultragenyx” or the “Company”), I am pleased to present to you this Amendment No. 1 (this “Amendment”), which amends the Offer of Employment Letter Agreement with you dated June 22, 2023 (the “Offer Letter”) as follows:
Warm Regards,
/s/ Emil D. Kakkis
Emil D. Kakkis, M.D., Ph.D.
Chief Executive Officer
I accept and agree the terms and conditions of this Amendment:
Signature: /s/ Howard Horn Dated: September 6, 2023
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