The Merck 023 HIV Vaccine Study is a Phase II proof of concept study of an
experimental vaccine that may one day prevent HIV infection or keep people who do become
HIV-infected healthier. You cannot get HIV infection or AIDS by receiving this vaccine.
The Prevention Project at the NYU Center for AIDS Research is now
conducting HVTN 504, an observational follow-up study to monitor volunteers previously enrolled in the Merck 023 HIV
vaccine study, also called “The Step Study.” For more information, click here
Further vaccinations in the
Merck and Co., Inc. vaccine study have been stopped because a recent analysis showed that the vaccine does
Unfortunately, the vaccine did not reduce the incidence of HIV infection and did not reduce the
amount of virus in people who became infected with HIV.
Despite these disappointing results, the current plan is to continue following current study
volunteers to monitor their health and offer them HIV testing and counseling. The information we
will learn may provide key insights that can guide future HIV vaccine development.
As always we would like to thank our volunteers and the community for supporting our research.
Finding an HIV vaccine can only move forward with the commitment of dedicated volunteers.
Click here to read the
Press Release from Merck and Co., Inc and the HIV Vaccine Trials Network.
- HIV-negative men who have sex with men and women who have sex with men, age 18-45, in
good general health
- Female volunteers must agree to use a method of birth control for the first 9 months of
- To test if the study vaccine lowers the chance of getting infected with HIV or lowers
the levels of HIV in the blood of people who become infected with HIV
- Volunteers are randomized (chosen randomly) to either vaccine or placebo
- Three injections of vaccine/placebo over 6 months
- You are closely monitored after each injection
Duration: 18 months on study; then twice-a-year follow up for 3.5 years
Phase II proof-of-concept, Double-blinded, Placebo Controlled
Click here to download Frequently Asked Questions about this Vaccine Study.
This is a Phase II proof of concept study of an experimental vaccine that may one day prevent HIV infection or keep people who do become HIV-infected healthier.
This study is being conducted to answer three questions
- Is it safe to give the study vaccine as an injection (shot) in a muscle?
- Does the study vaccine lower the chance of getting infected with HIV?
- If some people in this study get infected with HIV while the study is going on, does the study vaccine lower the levels of HIV in their blood?
All volunteers receive risk reduction counseling and HIV testing on a regular basis for the
length of the study. The vaccine is made of an adenovirus (a common virus that causes colds and
sore throats) that has been changed to contain man-made copies of genes from HIV. When the
vaccine is injected, it may cause your body to make proteins that look like they came from HIV.
These proteins may help your body make an infection-fighting response against HIV-1. The
vaccine does NOT contain live HIV. You cannot get HIV infection or AIDS by receiving this
For information, please call 212-263-0362.
Study Status: Closed to Enrollment; study volunteers are now in long-term follow-up.
- Michael Marmor, PhD
- Demetre Daskalakis, MD
- Gary Carlisle, RN
- Richard Hutt, RN
- Richard Silvera
- Dylan Stein
Study Volunteers Receive
- the opportunity to participate in cutting edge vaccine research
- frequent HIV testing and risk reduction counseling
- reimbursement for time