FDA Grants Priority Review Status to Prevnar 13 Marketing Application

COLLEGEVILLE, Pennsylvania - - Candidate vaccine designed to protect against the 13 most prevalent serotypes associated with pneumococcal disease –

Wyeth Pharmaceuticals, a division of Wyeth (NYSE: WYE), announced today that the U.S. Food and Drug Administration (FDA) granted priority review to the company’s Biologic License Application (BLA) for Prevnar 13*, Pneumococcal 13-valent Conjugate Vaccine (Diphtheria CRM(197) Protein), which was submitted on March 31. Priority review designation is given to products that, if approved, would be a significant therapeutic or public health advance. Based on this designation, Wyeth expects a regulatory decision within six months.

Wyeth is seeking an indication in the U.S. for Prevnar 13 for the prevention of invasive pneumococcal disease (IPD) and otitis media caused by the 13 serotypes included in the investigational vaccine in children aged two months through five years. Seven of these serotypes (4, 6B, 9V, 14, 18C, 19F and 23F) are included in Prevnar(R), Pneumococcal 7-valent Conjugate Vaccine (Diphtheria CRM(197) Protein) - the current global standard in PD prevention in infants and young children. The six additional serotypes (1, 3, 5, 6A, 7F and 19A) are associated with the greatest remaining burden of invasive disease. Both Prevnar 13 and Prevnar use CRM(197) - an immunological carrier protein with a 20-year history of use in pediatric vaccines.

“Since its launch in 2000, our 7-valent pneumococcal vaccine, Prevnar, has significantly reduced the incidence of pneumococcal disease among infants and young children in the United States. Recently, however, disease due to pneumococcal serotypes not found in Prevnar, particularly serotype 19A, have increased in prevalence in many regions of the world, and are a significant public health concern,” says Emilio Emini, Ph.D., Executive Vice President, Vaccine Research and Development, Wyeth Pharmaceuticals. “Prevnar 13, which builds on the scientific foundation of Prevnar, is designed to provide protection against the 13 most prevalent serotypes associated with pneumococcal disease.”

The Prevnar 13* submission to the FDA includes data from 13 Phase 3 studies, involving more than 7,000 infants and young children.

The Company initiated its global pediatric filings in late 2008 and, to date, has submitted regulatory applications for the 13-valent candidate vaccine in more than 40 countries worldwide. Prevnar 13 also is being studied in global Phase 3 clinical trials in adults, with regulatory submissions expected in 2010.

Pneumococcal Disease

Pneumococcal disease is complex and describes a group of illnesses, all caused by the bacterium Streptococcus pneumoniae. Pneumococcal disease affects both children and adults, and includes invasive infections such as bacteremia/sepsis and meningitis, as well as pneumonia and otitis media (middle ear infection).

Following the inclusion of Prevnar(R) into the routine pediatric immunization schedule in the United States, there has been a 98 percent (95% CI: 97%-99%) reduction in vaccine-type IPD and a 77 percent reduction in all IPD among children younger than 5 years of age through 2005, compared with a pre-licensure baseline. In addition, the incidence of disease caused by the seven conjugate vaccine serotypes declined 55 percent (95% CI: 51%-58%) among adults 50 years of age or older, an unvaccinated group. The Centers for Disease Control and Prevention has reported an increase in the incidence of IPD due to non-vaccine serotypes in children younger than 5 years of age and in adults 40 years of age and older; it is unknown whether these effects would be observed in other populations.

Most recently, serotype 19A, which is included in the candidate vaccine, has been increasing in prevalence in many regions of the world and is frequently resistant to antibiotics. In fact, serotype 19A has emerged as the predominant invasive pneumococcal serotype in the United States.

Prevnar, Pneumococcal 7-valent Conjugate Vaccine (Diphtheria CRM(197) Protein), is indicated for active immunization of infants and toddlers against serious invasive disease caused by Streptococcus pneumoniae, including bacteremia (bloodstream infection) and meningitis (infection of the membranes surrounding the brain and spinal cord) caused by the seven serotypes in the vaccine. The seven serotypes (strains) of S. pneumoniae included in the vaccine (4, 6B, 9V, 14, 18C, 19F, and 23F) are the strains that most commonly caused these serious diseases in children prior to the introduction of the vaccine. The routine vaccination schedule is 2, 4, 6, and 12 to 15 months of age.

Prevnar is also indicated for immunization of infants and toddlers against otitis media (ear infections) caused by the seven serotypes included in the vaccine. Protection against ear infections is expected to be less than that for invasive disease.

As with any vaccine, Prevnar may not protect all individuals receiving the vaccine from serious invasive disease cause by S. pneumoniae. This vaccine should not be used for treatment of active infection.

Important Safety Information for Prevnar

In clinical trials, the most frequently reported adverse events included injection site reactions, fever (less than or equal to 38 degreesC/100.4 degreesF), irritability, drowsiness, restless sleep, decreased appetite, vomiting, diarrhea, and rash.

Risks are associated with all vaccines, including Prevnar. Hypersensitivity to any vaccine component, including diphtheria toxoid, is a contraindication to its use. Prevnar does not protect 100% of children vaccinated. Immunization with Prevnar does not substitute routine diphtheria immunization.

About Wyeth Pharmaceuticals

Wyeth Pharmaceuticals, a division of Wyeth, has leading products in the areas of women’s health care, infectious disease, gastrointestinal health, central nervous system, inflammation, transplantation, hemophilia, oncology, vaccines and nutritional products.

Wyeth is one of the world’s largest research-driven pharmaceutical and health care products companies. It is a leader in the discovery, development, manufacturing and marketing of pharmaceuticals, vaccines, biotechnology products, nutritionals and non-prescription medicines that improve the quality of life for people worldwide. The Company’s major divisions include Wyeth Pharmaceuticals, Wyeth Consumer Healthcare and Fort Dodge Animal Health.

The statements in this press release that are not historical facts are forward-looking statements that are subject to risks and uncertainties that could cause actual results to differ materially from those expressed or implied by such statements. In particular, clinical trial data are subject to differing interpretations, and the views of regulatory agencies, medical and scientific experts and others may differ from ours. There can be no assurance that Prevnar 13 will ever receive regulatory approval or be successfully developed and commercialized. Other risks and uncertainties that could cause actual results to differ materially from those expressed or implied by forward-looking statements include, among others, risks related to our proposed merger with Pfizer, including satisfaction of the conditions of the proposed merger on the proposed timeframe or at all, contractual restrictions on the conduct of our business included in the merger agreement, and the potential for loss of key personnel, disruption in key business activities or any impact on our relationships with third parties as a result of the announcement of the proposed merger; the inherent uncertainty of the timing and success of, and expense associated with, research, development, regulatory approval and commercialization of our products and pipeline products; government cost-containment initiatives; restrictions on third-party payments for our products; substantial competition in our industry, including from branded and generic products; emerging data on our products and pipeline products; the importance of strong performance from our principal products and our anticipated new product introductions; the highly regulated nature of our business; product liability, intellectual property and other litigation risks and environmental liabilities; the outcome of government investigations; uncertainty regarding our intellectual property rights and those of others; difficulties associated with, and regulatory compliance with respect to, manufacturing of our products; risks associated with our strategic relationships; global economic conditions; interest and currency exchange rate fluctuations and volatility in the credit and financial markets; changes in generally accepted accounting principles; trade buying patterns; the impact of legislation and regulatory compliance; risks and uncertainties associated with global operations and sales; and other risks and uncertainties, including those detailed from time to time in our periodic reports filed with the Securities and Exchange Commission, including our current reports on Form 8-K, quarterly reports on Form 10-Q and annual report on Form 10-K, particularly the discussion under the caption “Item 1A, Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2008, which was filed with the Securities and Exchange Commission on February 27, 2009. The forward-looking statements in this press release are qualified by these risk factors. We assume no obligation to publicly update any forward-looking statements, whether as a result of new information, future developments or otherwise.

* Trademark * Trademark

Source: Wyeth Pharmaceuticals

Media, Lili Gordon of Wyeth Pharmaceuticals, +1-484-865-6671; or Douglas Petkus, +1-973-660-5218, or Investors, Justin Victoria, +1-973-660-5340, both of Wyeth