New England Journal of Medicine Publishes Efficacy and Safety Data for GARDASIL® in Males

February 02, 2011

WHITEHOUSE STATION, N.J. – Merck (known as MSD outside the United States
and Canada) announced today that data from the pivotal Phase III study with GARDASIL®
[Human Papillomavirus Quadrivalent (Types 6, 11, 16, and 18) Vaccine, Recombinant] in males
were published in the February 3 issue of the New England Journal of Medicine (NEJM).

In this study, GARDASIL was 89 percent effective against human papillomavirus (HPV) types 6- and 11- related genital warts in males aged 16 through 26. This Phase III study is the only study to demonstrate the efficacy of an HPV vaccine in males, and provided data that supported the U.S. Food and Drug Administration (FDA) approval of GARDASIL in October 2009 for the prevention of genital warts caused by HPV types 6 and 11 in boys and men ages 9 to 26 years.

In December 2010, GARDASIL was approved for the prevention of anal cancer caused
by HPV types 16 and 18 and for the prevention of anal intraepithelial neoplasia (AIN) grades 1,
2 and 3 (anal dysplasias and precancerous lesions) caused by HPV types 6, 11, 16 and 18, in
males and females 9 through 26 years of age, based on a substudy within this Phase III study.

“This publication as well as the recent FDA approval of GARDASIL to prevent anal
cancer caused by HPV types 16 and 18 underscores the importance of vaccinating both males
and females to help prevent certain HPV-related diseases,” said Dr. Anna Giuliano, chair,
Department of Epidemiology and Genetics, and Program Leader Cancer Epidemiology at the
Moffitt Cancer in Tampa, Florida, and the study’s lead author.

GARDASIL helps protect against the four types of HPV, specifically types 6, 11, 16, and
18, that cause the most disease. It is estimated that HPV types 16 and 18 account for
approximately 80 percent of anal cancers, 75 percent of cervical cancers, 70 percent of vaginal
cancers and 40 to 50 percent of vulvar cancers. HPV types 6 and 11 cause approximately
90 percent of all genital warts cases.

About HPV and GARDASIL
In the United States, an estimated 75 to 80 percent of males and females will be infected
with HPV in their lifetime. For most, HPV will clear on its own. However, for those who don't
clear certain types, HPV can cause cervical, vaginal and vulvar cancers in women and anal
cancer and genital warts in men and women. There is no way to predict who will or will not
clear the virus.

GARDASIL was first approved in the United States in June 2006. GARDASIL is
indicated for use in girls and young women 9 through 26 years of age for the prevention of
cervical, vulvar, vaginal and anal cancers caused by HPV types 16 and 18; genital warts
(condylomata acuminata) caused by HPV types 6 and 11; and precancerous or dysplastic
lesions caused by HPV types 6, 11, 16 and 18. GARDASIL is also approved in the United
States for use in boys and men ages 9 through 26 years of age for the prevention of anal cancer
caused by HPV types 16 and 18 and genital warts caused by HPV types 6 and 11; and
precancerous or dysplastic lesions caused by HPV types 6, 11, 16 and 18.

Important information about GARDASIL
GARDASIL does not eliminate the necessity for women to continue to undergo
recommended cervical cancer screening.

Recipients of GARDASIL should not discontinue anal cancer screening if it has been
recommended by a health care provider.

GARDASIL has not been demonstrated to provide protection against diseases from
vaccine and non-vaccine HPV types to which a person has previously been exposed through
sexual activity.

GARDASIL is not intended to be used for treatment of active external genital lesions;
cervical, vulvar, vaginal, and anal cancers; cervical intraepithelial neoplasia, vulvar
intraepithelial neoplasia, vaginal intraepithelial neoplasia, or anal intraepithelial neoplasia.
GARDASIL has not been demonstrated to protect against disease due to HPV types not
contained in the vaccine.

Not all vulvar, vaginal and anal cancers are caused by HPV, and GARDASIL protects
only against those vulvar, vaginal and anal cancers caused by HPV Types 16 and 18.
Select safety information
GARDASIL is contraindicated in individuals with hypersensitivity, including severe
allergic reactions to yeast, or after a previous dose of GARDASIL.

Because vaccinees may develop syncope, sometimes resulting in falling with injury,
observation for 15 minutes after administration is recommended. Syncope, sometimes
associated with tonic-clonic movements and other seizure-like activity, has been reported
following vaccination with GARDASIL. When syncope is associated with tonic-clonic
movements, the activity is usually transient and typically responds to restoring cerebral
perfusion.

GARDASIL is not recommended for use in pregnant women.

The most common adverse reaction was headache. Common adverse reactions that
were observed among recipients of GARDASIL at a frequency of at least 1.0 percent and
greater than placebo were: fever, nausea, dizziness; and injection-site pain, swelling, erythema,
pruritus and bruising.

Dosage and administration for GARDASIL
GARDASIL is a ready-to-use, three-dose, intramuscular vaccine. GARDASIL should be
administered in three separate intramuscular injections in the deltoid region of the upper arm or
in the higher anterolateral area of the thigh. The following dosage schedule is recommended:
First dose at elected date, second dose two months after the first dose and the third dose six
months after the first dose.

GARDASIL is approved in 122 countries
GARDASIL [Human Papillomavirus Quadrivalent (Types 6, 11, 16 and 18) Vaccine,
Recombinant] (sold in some countries as SILGARD®) has been approved in 122 countries, and
additional applications are currently under review with regulatory agencies in many more
countries around the world.

About Merck
Today's Merck is a global healthcare leader working to help the world be well. Merck is
known as MSD outside the United States and Canada. Through our prescription medicines,
vaccines, biologic therapies, and consumer care and animal health products, we work with
customers and operate in more than 140 countries to deliver innovative health solutions. We
also demonstrate our commitment to increasing access to healthcare through far-reaching
policies, programs and partnerships. For more information, visit www.merck.com.

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