Optimer Pharmaceuticals Appoints Hank McKinnell to Its Board of Directors

Optimer Pharmaceuticals, Inc. (Nasdaq: OPTR) today announced the appointment of Dr. Hank McKinnell to its Board of Directors. Dr. McKinnell is the former Chief Executive Officer and former Chairman of the Board of Directors of Pfizer Inc. He is currently Chairman of the Accordia Global Health Foundation, an organization dedicated to fighting infectious diseases in Africa, and is a member of the boards of Moody's Corporation, Angiotech Pharmaceutical, Inc., and privately-held Emmaus Medical, Inc.

"Hank McKinnell's extensive business experience, deep interest in the opportunities of the biotech industry, and dedication to profound social advances to health and wellness for patients globally makes him a valuable addition to Optimer's Board of Directors," said Pedro Lichtinger, President and CEO of Optimer. "Our ability to attract someone with Hank's business acumen and demonstrated leadership talent is an inspiration to our team. His experience in economics, strategy and business operations has been instrumental in pioneering an approach for marrying innovation, health and wellness and market access as the essential formula for success in today's pharmaceutical marketplace. We at Optimer will benefit from his tremendous skillset and insights."

"Optimer has a unique opportunity to drive some of the most exciting innovation in health care," said Dr. McKinnell. "Fidaxomicin is a cutting edge antibiotic for c.diff, a bacterial infection putting increasing pressure on hospitals and placing the sick and elderly at particular risk, and addresses a growing health challenge with the aging of our population – especially as the first of the Baby Boomers turn 65 this January. With the potential FDA approval of fidaxomicin this year, it is an exciting time to be joining Optimer's Board and I look forward to working with the Optimer team."

Dr. McKinnell joined Pfizer in 1971 in Tokyo and over the years held positions of increasing responsibility around the world, including service as President of Pfizer Asia. In 1984, Dr. McKinnell relocated to New York, where he served as Vice President-Strategic Planning, Chief Financial Officer, President-Pfizer Medical Device Group, President-Pfizer Pharmaceuticals Group, and President and Chief Operating Officer. He was named Chairman and Chief Executive Officer in 2001 and served in this role until his retirement in 2006.

He is Chairman Emeritus of the Business Roundtable, an association of 170 CEOs of America's largest companies; the Pharmaceutical Research Manufacturers Association; the Food and Drug Law Institute; and the Medical Device Manufacturers Association. He is a member of the Academic Alliance and Chairman of the Academic Alliance Foundation, which supports infectious diseases prevention, care and treatment in Sub-Sahara Africa. Dr. McKinnell is also a Senior Advisor to TH Lee Private Equity Partnership, Toyota, and Alexander Proudfoot. He also served as Vice Chairman and a member of the Board of Trustees of the World Economic Forum, and on the President's Advisory Council on HIV/AIDS.

Recent honors include, among others, the Grand Cordon of the Order of the Rising Sun, Japan's highest award to those other than members of the Imperial Family and heads of state; the United Nations Association of the United States of America's Global Leadership Award; the Woodrow Wilson Institute Corporate Service Award; and Stanford University's Graduate School of Business Arbuckle Award and Excellence in Leadership Award.

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.

Optimer Pharmaceuticals Inc. Reports Operating Results

OPTIMER PHARMACEUTICALS INC. is a biopharmaceutical company focused on discovering developing & commercializing innovative anti-infective products for the treatment of serious infections. Optimer is currently focused on discovering developing & commercializing innovative anti-infective products in diseases of unmet needs and where current therapeutic options have limitations. Optimer has two late-stage anti-infective product candidates. OPT-80 currently in two pivotal Phase 3 clinical trials is being developed for the treatment of Clostridium difficile infection the most common hospital-acquired diarrhea. Prulifloxacin also in two pivotal Phase 3 clinical trials is an antibiotic being developed for the treatment of travelers? diarrhea a form of infectious diarrhea. The Company has also licensed technologies and therapeutic targets from The Scripps Research Institute and The Memorial Sloan-Kettering Cancer Center. These licenses form the core of Optimer's carbohydrat Optimer Pharmaceuticals Inc. has a market cap of $420 million; its shares were traded at around $12.71 with and P/S ratio of 410.4.
Highlight of Business Operations:Grant Revenues. Grant revenues for the three months ended March 31, 2009 and 2008 were $83,000 and $487,000, respectively. The decrease of $404,000, or 83%, was primarily due to the conclusion of one of two National Institutes of Health grants.

Research and Development Expense. Research and development expense for the three months ended March 31, 2009 and 2008 was $8.8 million and $6.9 million, respectively, an increase of $1.9 million, or 27%. The increase was primarily due to an increase in development and regulatory expenses related to fidaxomicin and prulifloxacin.

General and Administrative Expense. General and administrative expense for the three months ended March 31, 2009 and 2008 was $2.0 million and $1.7 million, respectively. The increase of $311,000, or 18%, was due to higher compensation expenses, including $318,000 of stock compensation expense, an increase of $77,000 over the same period in the prior year, as well as higher consulting expenses.

Interest Income and Other, net. Net interest income and other for the three months ended March 31, 2009 and 2008 was $187,000 and $581,000, respectively. The decrease was primarily due to lower average balances as well as lower interest rates on cash, cash equivalents and investments.

As of March 31, 2009, cash, cash equivalents and short-term investments totaled approximately $62.6 million as compared to $39.3 million as of December 31, 2008, an increase of approximately $23.3 million. The increase in our cash, cash equivalents and short-term investments was primarily due to the $32.9 million raised in a registered direct offering of our common stock in March 2009.

In February 2007, we regained worldwide rights to fidaxomicin from Par under a prospective buy-back agreement. We are obligated to pay Par a one-time $5.0 million milestone payment, a 5% royalty on net sales by us or our affiliates of fidaxomicin in North America and Israel, and a 1.5% royalty on net sales by us or our affiliates of fidaxomicin in the rest of the world. In addition, in the event we license our right to market fidaxomicin in the rest of the world, we will be required to pay Par a 6.25% royalty on net revenues we receive related to fidaxomicin. We are obligated to pay each of these royalties, if any, on a country-by-country basis for seven years commencing on the applicable commercial launch in each such country. In connection with the exercise of our rights under the prospective buy-back agreement, Par assigned to us a supply agreement with Biocon. Under this agreement, Biocon is obligated to supply to us our requirements of the fidaxomicin active pharmaceutical ingredients for certain markets. We may be obligated to pay a $3.0 million prepayment to Biocon, subject to future set-offs.