Wyeth Submits Marketing Application to FDA for its 13-Valent Vaccine for the Prevention of Pneumococcal Disease in Infants and Toddlers

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 it has submitted a Biologic License Application (BLA) to the U.S. Food
and Drug Administration (FDA) for Prevnar 13(TM), Pneumococcal 13-valent
Conjugate Vaccine (Diphtheria CRM(197) Protein). Last year, the FDA granted
Prevnar 13 Fast Track designation, which is designed to facilitate review of
products that address serious or potentially life-threatening conditions for
which there is an unmet medical need.

Prevnar 13 is designed to protect against the 13 most prevalent serotypes
associated with pneumococcal disease (PD), the leading cause of
vaccine-preventable death worldwide. 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.

“We are pleased that, with this milestone, we are now one step closer to
bringing Prevnar 13 to infants and children,” says Emilio Emini, Ph.D.,
Executive Vice President, Vaccine Research and Development, Wyeth
Pharmaceuticals. “Prevnar, our currently available vaccine, has both proven
clinical efficacy and documented effectiveness, which has resulted in a
significant public health impact. Prevnar 13 builds on the scientific
foundation of Prevnar and, if approved, will provide coverage for the 13 most
prevalent pneumococcal serotypes associated with pneumococcal disease,
including serotype 19A, which has emerged as a serious public health threat
in the United States and around the world.”

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 is also 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
of which are caused by the bacterium Streptococcus pneumoniae. PD 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 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.

Indication

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
Prevnar. 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 (greater than or equal to 38 degrees Celsius
/100.4 degrees Fahrenheit), 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 our regulatory submissions for Prevnar 13 will be accepted for review by
regulatory agencies or 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.

Source: Wyeth Pharmaceuticals

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