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Study on the Safety of Doravirine and Islatravir for HIV Patients Who Previously Participated in Doravirine/Islatravir Trials

Verified siteInvestigationalNo 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 infection using a medication called Doravirine/Islatravir (also known by the code name MK-8591A). The medication is taken as a film-coated tablet and is designed to be taken once daily. The purpose of the study is to evaluate the safety and tolerability of this treatment in participants who have previously received it in earlier clinical studies.

Participants in this study will continue to take the Doravirine/Islatravir tablet as part of their treatment for HIV infection. The study will monitor participants over a period to gather information on any serious adverse events or reasons for discontinuing the treatment due to adverse effects. This information will help researchers understand how well the treatment is tolerated by those who have already been using it.

The study is open-label, meaning that both the participants and the researchers know which treatment is being administered. This trial is a continuation for those who have already been part of previous studies involving Doravirine/Islatravir, allowing them to continue their treatment while contributing to the collection of important safety data.

The research process

The trial runs in 4 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Participation begins after completing a previous clinical study involving the combination of doravirine and islatravir.

    Eligibility requires having received clinical benefit from the previous study and weighing at least 35 kg.

    Female participants must not be pregnant or breastfeeding and must agree to use contraception if of childbearing potential.

  2. Step 2

    Medication administration

    The medication, known as MK-8591A, is taken orally as a film-coated tablet.

    The dosage consists of 100 mg of doravirine and 0.75 mg of islatravir, administered once daily.

  3. Step 3

    Monitoring and evaluation

    The main objective is to assess the safety and tolerability of the medication through accumulated safety data.

    Monitoring includes tracking any serious adverse events and any discontinuation of treatment due to adverse events.

  4. Step 4

    Study duration

    The study is estimated to conclude by October 7, 2025.

    Participants continue to receive the medication until the study's end date, unless otherwise advised by the study team.

Who can join the trial?

6 criteria

  • The patient must currently be taking a specific combination tablet called **DOR/ISL** in a clinical study and have completed the last treatment visit.
  • The patient should be considered by the study doctor to have benefited from the **DOR/ISL** treatment and should continue to need this treatment.
  • The patient can be male or female and must weigh at least **35 kg** (about 77 pounds) at the time of agreeing to participate in the study.
  • If the patient is female, she must not be pregnant or breastfeeding. She must meet at least one of the following conditions:
    • She is not able to have children.
    • If she can have children, she agrees to either not be sexually active or use a reliable method of birth control during the study and for at least 6 weeks after the last dose of the study medication.
    • If she is pregnant, she may continue with the study treatment if allowed by local rules and based on available information or local care guidelines.

Who cannot join the trial?

4 criteria

  • Individuals who do not have an HIV infection cannot participate. HIV infection is a condition caused by the human immunodeficiency virus, which affects the immune system.
  • Participants must be within certain age ranges, specifically those categorized as age range 4 and 3. This typically refers to specific age groups defined by the study.
  • Both male and female participants are eligible, but those who do not fit these categories may be excluded.
  • Individuals from a vulnerable population are not selected for this study. A vulnerable population includes groups who may have limited ability to protect their own interests.
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Investigated drugs

  • Doravirine

    is a medication used to treat HIV-1 infection. It works by blocking a specific enzyme that the virus needs to multiply, helping to control the infection and improve the immune system.

  • Islatravir

    is another medication used in the treatment of HIV-1 infection. It helps to prevent the virus from multiplying by interfering with its ability to replicate, which aids in managing the infection and maintaining immune function.

What is already known about the treatment

Doravirine/Islatravir – This medication is administered orally in the form of a tablet and is currently being studied in clinical trials for the treatment of HIV infection. It is in the phase of evaluating its safety and tolerability, with ongoing research to confirm its effectiveness. The main therapeutic indication for Doravirine/Islatravir is the treatment of HIV-1 infection. At the molecular level, Doravirine works by inhibiting the reverse transcriptase enzyme, which is crucial for the replication of the HIV virus, while Islatravir acts as a nucleoside reverse transcriptase translocation inhibitor, further preventing viral replication. This combination falls under the pharmacological classification of antiretroviral agents.

Investigated diseases

HIV infection – Human Immunodeficiency Virus (HIV) infection is a condition caused by a virus that attacks the immune system, specifically targeting CD4 cells, which are crucial for fighting infections. Over time, if untreated, HIV can weaken the immune system, making the body more susceptible to other infections and diseases. The virus is primarily transmitted through contact with infected bodily fluids, such as blood, semen, vaginal fluids, and breast milk. In the early stages, individuals may experience flu-like symptoms, but as the infection progresses, it can lead to more severe health issues. Without intervention, HIV can advance to Acquired Immunodeficiency Syndrome (AIDS), where the immune system is severely compromised. Regular monitoring and management are essential to control the progression of the disease.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-512215-53-00Protocol codeMK-8591A-033Estimated enrolment606 patientsSponsorMerck Sharp & Dohme LLC

sourced from the EU Clinical Trials Register and site verification

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