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Study on Switching HIV Treatment to Doravirine and Islatravir for Patients with HIV-1

Fast replyRegistered drugNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying the treatment of HIV-1 infection, a virus that attacks the body's immune system. The study involves participants who are currently managing their condition with a medication called Biktarvy, which contains the active substances emtricitabine, tenofovir alafenamide, and bictegravir. The trial aims to evaluate the effects of switching to a new combination treatment called Doravirine/Islatravir (also known by the code name MK-8591A), which includes the active substances doravirine and islatravir.

The purpose of the study is to assess the effectiveness and safety of switching from Biktarvy to Doravirine/Islatravir in people who have their HIV-1 under control. Participants will be randomly assigned to either continue their current treatment with Biktarvy or switch to the new combination of Doravirine/Islatravir. Some participants may receive a placebo, which looks like the real medication but does not contain active ingredients. The study will last for a period of 96 weeks, during which participants will have regular check-ups to monitor their health and the virus levels in their blood.

Throughout the study, researchers will collect data to determine how well the new treatment works in keeping the virus suppressed and how safe it is for participants. The trial will also look at any side effects experienced by participants and any changes in their immune system. This information will help in understanding whether the new treatment could be a viable option for people living with HIV-1.

The research process

The trial runs in 6 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Upon joining the study, you will be randomly assigned to one of two groups. One group will continue taking their current medication, Biktarvy, which is a combination of three drugs: emtricitabine, tenofovir alafenamide, and bictegravir. The other group will switch to a new medication, a combination of doravirine and islatravir.

  2. Step 2

    Medication administration

    If you are in the group continuing with Biktarvy, you will take one film-coated tablet orally once a day. Each tablet contains 50 mg of bictegravir, 200 mg of emtricitabine, and 25 mg of tenofovir alafenamide.

    If you are in the group switching to the new medication, you will take one film-coated tablet containing 100 mg of doravirine and 0.25 mg of islatravir orally once a day.

  3. Step 3

    Regular check-ups

    Throughout the study, you will have regular check-ups to monitor your health and the effectiveness of the medication. These check-ups will include blood tests to measure the amount of HIV-1 RNA in your blood and to check your CD4+ T-cell count, which is an important part of your immune system.

  4. Step 4

    Monitoring and reporting

    You will be asked to report any side effects or adverse events you experience during the study. This information is crucial for evaluating the safety and tolerability of the medications.

  5. Step 5

    Study duration

    The study will last for approximately 48 weeks, with the possibility of extending to 96 weeks. During this time, your health and the effectiveness of the medication will be closely monitored.

  6. Step 6

    End of study

    At the end of the study, you will have a final check-up to assess your health and the overall outcomes of the treatment. The results will contribute to understanding the effectiveness and safety of switching to the new medication.

Who can join the trial?

4 criteria

  • Participants must be 18 years of age or older.
  • Must be HIV-1 positive with a very low level of the virus in the blood (plasma HIV-1 RNA <50 copies/mL).
  • Must have been taking a specific HIV treatment called BIC/FTC/TAF and have had the virus under control (HIV-1 RNA <50 copies/mL) for at least 3 consecutive months before joining the study. There should be no history of the treatment not working in the past.
  • If female, must either not be able to become pregnant or, if able to become pregnant, must not be pregnant or breastfeeding. Must also agree to use a reliable method of birth control or not engage in heterosexual intercourse during the study.

Who cannot join the trial?

5 criteria

  • Patients who do not have **HIV-1 infection** cannot participate.
  • Patients who are not within the specified age range cannot participate.
  • Patients who are not part of the specified clinical trial groups cannot participate.
  • Patients who are not male or female cannot participate.
  • Patients who are not part of the vulnerable population selected for the study cannot participate.
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Investigated drugs

  • Doravirine/Islatravir

    is a combination of two medications used to treat HIV-1 infection. Doravirine helps to block the virus from multiplying in the body, while Islatravir works by interfering with the virus's ability to reproduce. Together, they help to keep the virus under control and maintain a low level of HIV in the blood.

  • Bictegravir/Emtricitabine/Tenofovir Alafenamide

    is a combination of three medications used to treat HIV-1 infection. Bictegravir helps prevent the virus from multiplying, Emtricitabine works by blocking the virus's ability to reproduce, and Tenofovir Alafenamide helps to reduce the amount of virus in the body. This combination helps to control the infection and maintain a low level of HIV in the blood.

What is already known about the treatment

Doravirine/Islatravir – This medication is taken orally in the form of a pill and is used to treat HIV-1 infection. It is currently being studied in clinical trials to see if it is effective and safe for people who are already controlling their HIV with another medication. Doravirine/Islatravir works by blocking the virus from multiplying in the body, which helps keep the virus at low levels. It belongs to a class of drugs known as antiretrovirals, which are used to manage HIV infections.

Investigated diseases

HIV-1 infection – Human Immunodeficiency Virus type 1 (HIV-1) infection is a viral condition that targets the immune system, specifically the CD4+ T cells, which are crucial for immune response. As the virus replicates, it gradually depletes these cells, weakening the body's ability to fight infections and diseases. The progression of the infection can lead to a significant reduction in CD4+ T cell count, making the individual more susceptible to opportunistic infections. Over time, if untreated, the infection can advance to Acquired Immunodeficiency Syndrome (AIDS), characterized by a severely compromised immune system. The virus is primarily transmitted through contact with infected bodily fluids, such as blood, semen, vaginal fluids, and breast milk. The progression of the disease can vary greatly among individuals, influenced by factors such as viral load, genetic factors, and overall health.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2022-502079-49-00Protocol codeMK-8591A-052Estimated enrolment501 patientsSponsorMerck Sharp & Dohme LLC

sourced from the EU Clinical Trials Register and site verification

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).