UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT
Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):  January 10, 2011

OPTIMER PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

10110 Sorrento Valley Road, Suite C

San Diego, CA 92121
(Address of principal executive offices, including zip code)

Registrant’s telephone number, including area code: (858) 909-0736

N/A

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o            Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o            Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o            Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o            Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 5.02               Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

(d)  On January 10, 2011, our Board of Directors appointed Henry A. McKinnell, Jr. Ph.D., to serve as a director of the Company.  Dr. McKinnell was appointed to serve as a Class II director and will be subject to reelection at our 2012 annual meeting of stockholders. In connection with his appointment, Dr. McKinnell received stock options to purchase up to an aggregate of 30,000 shares of our common stock, pursuant to the terms of our 2006 Equity Incentive Plan. Additionally, in connection with his appointment as a director, Dr. McKinnell entered into our standard form of indemnification agreement.

Dr. McKinnell served as Chairman of the Board of Pfizer Inc., a pharmaceutical company, from May 2001 until his retirement in December 2006 and Chief Executive Officer from January 2001 to July 2006. He served as President of Pfizer Inc. from May 1999 to May 2001, and as President of Pfizer Pharmaceuticals Group from January 1997 to April 2001. Dr. McKinnell served as Chief Operating Officer of Pfizer from May 1999 to December 2000 and as Executive Vice President from 1992 to 1999. Dr. McKinnell currently serves as lead independent director of Moody’s Corporation and is a director of Angiotech Pharmaceuticals, Inc. Dr. McKinnell also serves as Chairman of the Board of the Accordia Global Health Foundation. He is Chairman Emeritus of the Connecticut Science Center, and is a member of the Academic Alliance for AIDS Care and Prevention in Africa. He served as director of Pfizer and ExxonMobil Corporation until 2007 and John Wiley & Sons until 2005.  Dr. McKinnell holds a Bachelor’s Degree in business from the University of British Columbia, and M.B.A. and Ph.D. degrees from the Stanford University Graduate School of Business.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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