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Study on HIV-1 Treatment for Patients New to Therapy: Comparing Doravirine/Islatravir with a Drug Combination

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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 immune system. The study involves two different treatment groups. One group will receive a combination of medications called doravirine and islatravir, known together as MK-8591A. The other group will receive a combination of bictegravir, emtricitabine, and tenofovir alafenamide, which are combined in a medication called Biktarvy. The purpose of the study is to evaluate the effectiveness, safety, and tolerability of these treatments in people who have not previously taken antiretroviral therapy, which is a type of medication used to treat HIV.

Participants in the study will be randomly assigned to one of the two treatment groups. The study is designed to be double-blind, meaning neither the participants nor the researchers will know which treatment each participant is receiving. This helps to ensure that the results are not biased. The study will last for a period of 96 weeks, with regular check-ups to monitor the participants' health and the effectiveness of the treatment. The main goal is to see how well the treatments can reduce the amount of HIV in the blood to very low levels, specifically less than 50 copies per milliliter, by Week 48.

Throughout the study, the safety and side effects of the treatments will be closely monitored. Participants will have regular visits with healthcare professionals to review their health status and any potential side effects. The study will also look at changes in the participants' immune system, specifically the number of CD4+ T-cells, which are a type of white blood cell that plays a crucial role in the immune response. The study aims to provide valuable information on the best treatment options for people living with HIV-1 who are new to antiretroviral therapy.

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, the participant is confirmed to be HIV-1 positive and has not received any prior antiretroviral therapy. The participant is at least 18 years old and meets other eligibility criteria.

  2. Step 2

    Randomization

    The participant is randomly assigned to one of two groups. One group receives a combination of doravirine and islatravir (DOR/ISL 100 mg/0.25 mg) once daily. The other group receives a combination of bictegravir, emtricitabine, and tenofovir alafenamide (BIC/FTC/TAF 50 mg/200 mg/25 mg) once daily.

  3. Step 3

    Treatment administration

    The participant takes the assigned medication orally in the form of film-coated tablets. The medication is taken once daily for the duration of the study.

  4. Step 4

    Monitoring and assessments

    Throughout the study, the participant's health is monitored regularly. This includes checking the levels of HIV-1 RNA in the blood to assess the effectiveness of the treatment. The goal is to achieve less than 50 copies/mL of HIV-1 RNA by Week 48.

    Safety and tolerability are also evaluated by reviewing any adverse events experienced by the participant.

  5. Step 5

    Follow-up evaluations

    At Week 48, the primary evaluation of the treatment's effectiveness and safety is conducted. Secondary evaluations occur at Weeks 96 and 144 to assess long-term outcomes, including changes in CD4+ T-cells and body weight.

  6. Step 6

    Completion of the study

    The study is estimated to conclude by August 6, 2029. The participant's involvement continues until the study's end, unless they choose to discontinue earlier due to adverse events or other reasons.

Who can join the trial?

4 criteria

  • The person must be **18 years or older** and can be of any sex or gender.
  • The person must have **HIV-1**, which is a type of virus, and have a certain amount of the virus in their blood, specifically **500 copies/mL or more** at the time of screening.
  • The person must be **new to antiretroviral therapy (ART)**, meaning they have not received any treatment for HIV-1 since being diagnosed.
  • If the person is a female who can have children, she must not be pregnant or breastfeeding. She must also agree to use a reliable method of birth control or not have heterosexual intercourse during the study.

Who cannot join the trial?

4 criteria

  • Individuals who do not have an HIV-1 infection cannot participate. HIV-1 is a type of virus that affects the immune system.
  • Participants must be within the specified age range, which is not detailed here, but typically means they must be adults or older teenagers.
  • Both males and females are eligible, so gender is not a reason for exclusion.
  • Individuals who are part of a vulnerable population, such as those unable to give consent or those with certain disabilities, are not excluded based on this information.
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Investigated drugs

  • Doravirine/Islatravir (DOR/ISL)

    is a combination medication used in this clinical trial to treat individuals who are newly diagnosed with HIV-1. It is taken once daily and is being studied for its ability to reduce the amount of HIV in the blood, as well as its safety and how well it is tolerated by patients.

  • Bictegravir/Emtricitabine/Tenofovir Alafenamide (BIC/FTC/TAF)

    is another combination medication used in the trial as a comparison to DOR/ISL. This medication is also used to treat HIV-1 and is taken once daily. The trial aims to compare its effectiveness in reducing HIV levels in the blood and its safety profile to that of DOR/ISL.

What is already known about the treatment

Doravirine/Islatravir – This medication is administered orally in the form of a once-daily tablet. It is currently being studied in a Phase 3 clinical trial for its effectiveness in treating HIV-1 infection in individuals who have not previously received treatment. The main therapeutic indication is to reduce the viral load in patients with HIV-1. Doravirine works by inhibiting the reverse transcriptase enzyme, preventing the virus from replicating, while Islatravir acts as a nucleoside reverse transcriptase translocation inhibitor, further blocking viral replication. This combination is classified as an antiretroviral medication.

Investigated diseases

HIV-1 Infection – HIV-1 infection is caused by the human immunodeficiency virus type 1, which attacks the immune system, specifically targeting CD4+ T-cells. As the virus replicates, it reduces the number of these cells, weakening the body's ability to fight off infections and diseases. The progression of the infection can vary, but without intervention, it typically leads to a significant decline in immune function. Over time, this can result in the development of acquired immunodeficiency syndrome (AIDS), characterized by severe immune system damage. The virus is primarily transmitted through contact with infected bodily fluids, such as blood, semen, and vaginal fluids. Regular monitoring of viral load and CD4+ T-cell count is crucial in managing the infection.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2022-502099-22-01Protocol codeMK-8591A-053Estimated enrolment642 patientsSponsorMerck Sharp & Dohme LLC

sourced from the EU Clinical Trials Register and site verification

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