May 5, 2010 To: Michael Chang Dear Michael:Optimer Pharmaceuticals Inc • May 6th, 2010 • Pharmaceutical preparations • California
Company FiledMay 6th, 2010 Industry JurisdictionThis letter sets forth the terms and conditions of the separation and consulting agreement (the “Agreement”) that Optimer Pharmaceuticals, Inc. (the “Company”) is offering to you to aid in your employment transition.