Study Name

A Randomized, Double-Blind, Placebo-Controlled Study of a Single Dose of Pembrolizumab in HIV- infected Patients

Study Number


Goal of Study

The NIH is conducting a research study for people living with HIV and on HIV medications whose CD4 t-cell count is >100 but <350, with an undetectable HIV viral load. The purpose of this research study is to see if a drug called pembrolizumab is safe to use in people with HIV, and if it strengthens the immune system. Pembrolizumab is considered an experimental treatment in this study because it is not approved by the Food and Drug Administration (FDA) for treating HIV infection. This means that we don't know whether pembrolizumab is safe to use in HIV-infected people or whether it will work to treat your HIV infection. Pembrolizumab is made by the drug company Merck and sold under the name Keytruda. The FDA has approved it for treating different types of cancers including lung cancer and skin cancer. The FDA has given us permission to use it in this study. This is among the earliest studies of pembrolizumab in people who have HIV infection but do not have cancer.

Study Design

A total of 20 individuals at least 18 years old are expected to participate in this study. All participants will be in one of two groups. One group will get the study drug, and the other group will get a "placebo." A placebo looks just like the study drug but does not have any active drug in it. Researchers use a placebo to see if the study drug is more or less safe or effective than not taking anything. Whether you get the study drug or placebo will be decided randomly. This is like deciding by flipping a coin. Overall, 15 people will get the study drug and 5 will get the placebo. Neither you nor the study team will know which group you are in, but in the case of an emergency, we can find out. 

Subjects who enter the study will complete about 12 study visits over a period of approximately one year. The study drug or placebo will be administered at your first visit. After your final study visit, you will then receive a total of four follow-up telephone calls, at 12-week intervals. Your participation ends with the final follow-up call, which will take place approximately 96 weeks after your first study visit. Your study visits will be at the NIH Clinical Center in Bethesda, Maryland. Study procedures also include physical exams and blood collection. Volunteers will be compensated.

Eligibility Criteria

  • You are at least 18 years old and living with HIV
  • You have taken HIV medications continuously for at least one year
  • You have a CD4 (t-cell) count over 100 but less than 350 at screening
  • You have had an undetectable HIV viral load for at least the past 12 months 
  • You do not have a history of stroke or seizure; do not have any active lung, heart, kidney, or autoimmune conditions; do not have active hepatitis; do not have diabetes; have not had cancer in the past five years

Visit ClinicalTrials.gov for details.

Contact Information

Volunteer or get more information
Toll free: 1-800-411-1222
TTY: 1-866-411-1010
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Participating in Research

Watch a series of short informational videos about participating in clinical trials. These videos are intended to help potential participants understand how research works, what questions they should consider asking, and things to think about when deciding whether or not to participate in a study.

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