November 13, 2007
STEP Study Volunteers to be Informed Whether They Received Vaccine or Placebo
SEATTLE, Nov. 13, 2007 – Merck & Co., Inc. and the HIV Vaccine Trials Network (HVTN)
today announced that study volunteers in the STEP study of Merck's HIV vaccine (V520) will be
told whether they received vaccine or placebo, and all study volunteers will be encouraged to
continue to return to their study sites on a regular basis for ongoing risk reduction counseling
and study-related tests. Study investigators are being advised this week to provide this
information to the volunteers; volunteers will receive additional information about the unblinding
process directly from study sites.
The study was co-sponsored by Merck & Co., Inc.; the National Institute of Allergy and
Infectious Diseases (NIAID), part of the U.S. National Institutes of Health; and the HIV Vaccine
Trials Network (HVTN), which is funded by NIAID. The STEP Study Oversight Committee,
which is comprised of representatives from the three study co-sponsors, made the decision to
unblind study volunteers following extensive discussion of the STEP results at last week's
meeting of the HVTN by researchers, members of the community advisory boards of the study
sites and other study site staff, including clinic coordinators and community educators.
On Sept. 21, 2007, the trial sponsors announced that vaccinations in the study were
discontinued because the vaccine was not effective, and the available results from the study
were presented at last week's meeting of the HVTN. For more information, please see:
About Merck
Merck & Co., Inc. is a global research-driven pharmaceutical company dedicated to
putting patients first. Established in 1891, Merck currently discovers, develops, manufactures
and markets vaccines and medicines to address unmet medical needs. The Company devotes
extensive efforts to increase access to medicines through far-reaching programs that not only
donate Merck medicines but help deliver them to the people who need them. Merck also
publishes unbiased health information as a not-for-profit service. For more information, visit
www.merck.com.
About the HIV Vaccine Trials Network
The HVTN is an international collaboration of scientists and institutions whose goal is to
accelerate the search for an HIV vaccine by sharing trial results and facilitating parallel, concurrent
testing. The HVTN is a unique hybrid that combines the depth and diversity of the academic
community and the flexibility of a commercial drug company. Working with industry and
government, the HVTN seeks to expedite and coordinate the trial process, advancing vaccine
candidates and building a body of knowledge about HIV vaccine trials.
The HVTN is supported through a cooperative agreement with the National Institute of
Allergy and Infectious Diseases, which is a component of the U.S. National Institutes of Health.
The Network and NIAID have a close, cooperative working relationship, with shared attention to the
intellectual and scientific issues. The Network’s headquarters are at Fred Hutchinson Cancer
Research Center in Seattle.
Merck forward-looking statement
This press release contains "forward-looking statements" as that term is defined in the
Private Securities Litigation Reform Act of 1995. These statements are based on management’s
current expectations and involve risks and uncertainties, which may cause results to differ
materially from those set forth in the statements. The forward-looking statements may include
statements regarding product development, product potential or financial performance. No forwardlooking
statement can be guaranteed, and actual results may differ materially from those projected.
Merck undertakes no obligation to publicly update any forward-looking statement, whether as a
result of new information, future events, or otherwise. Forward-looking statements in this press
release should be evaluated together with the many uncertainties that affect Merck's business,
particularly those mentioned in the risk factors and cautionary statements in Item 1A of Merck's
Form 10-K for the year ended Dec. 31, 2006, and in its periodic reports on Form 10-Q and
Form 8-K, which the company incorporates by reference.
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