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Study on Antiviral Therapy with Nirmatrelvir and Remdesivir for Immunocompromised COVID-19 Patients

Verified siteRegistered 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 treatments for COVID-19 in individuals with weakened immune systems. The study will explore the effectiveness of two antiviral medications: Paxlovid, which contains the active substance nirmatrelvir, and Veklury, which contains remdesivir. Paxlovid is taken orally as film-coated tablets, while Veklury is administered through an intravenous infusion, meaning it is given directly into a vein.

The purpose of the study is to determine if using a combination of these two medications or extending the duration of Paxlovid treatment from 5 to 10 days can help reduce the presence of the virus in the body. Participants will be randomly assigned to different treatment groups, and some may receive a placebo. The study will monitor the virus levels in participants' nasal swabs over a period of time to see how well the treatments work.

Throughout the study, participants will have regular check-ups to assess their health and the effectiveness of the treatment. The study aims to provide valuable information on how to best treat COVID-19 in people with compromised immune systems, potentially leading to improved care and outcomes for this vulnerable group.

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 required to sign an informed consent form. This form confirms your understanding of the study requirements and your willingness to participate.

    Eligibility criteria include being 16 years or older, having a confirmed COVID-19 infection, and being immunocompromised. Your body weight must be over 40 kg.

  2. Step 2

    Initial assessment

    An initial assessment will be conducted to confirm your eligibility. This includes a laboratory test to confirm SARS-CoV-2 infection and an evaluation of your health status.

  3. Step 3

    Treatment phase

    You will receive a combination of two antiviral medications: nirmatrelvir and remdesivir.

    Nirmatrelvir will be administered orally in the form of Paxlovid 150 mg + 100 mg film-coated tablets. The duration of administration may vary between 5 to 10 days.

    Remdesivir will be administered intravenously as Veklury 100 mg powder for concentrate for solution for infusion.

  4. Step 4

    Monitoring and follow-up

    Your health and response to the treatment will be monitored regularly. Nasopharyngeal swabs will be taken to measure the viral load at days 5, 10, 14, and 21.

    Blood samples may also be collected to assess the presence of the virus and your body's response to the treatment.

  5. Step 5

    End of treatment evaluation

    At the end of the treatment period, an evaluation will be conducted to determine the effectiveness of the antiviral therapy.

    The primary goal is to assess the reduction in the SARS-CoV-2 positivity rate in your nasopharyngeal swabs.

  6. Step 6

    Long-term follow-up

    You will be followed up until day 90 to monitor any long-term effects of the treatment and to ensure your well-being.

    This includes checking for any adverse events or the need for additional treatments.

Who can join the trial?

14 criteria

  • Must have a laboratory-confirmed SARS-CoV-2 infection using a test called RT-PCR.
  • Must have asymptomatic (no symptoms) or mild to moderate COVID-19 as defined by a specific scale (WHO progression scale ≤5).
  • Must be 16 years of age or older.
  • Must have a body weight greater than 40 kg (about 88 pounds).
  • Must be immunocompromised, meaning having a weakened immune system due to certain conditions or treatments. This includes:
    • HIV infection with a specific low level of CD4 cells.
    • Low levels of certain white blood cells (neutropenia or lymphocytopenia).
    • Hereditary immunodeficiencies (genetic conditions affecting the immune system).
    • Taking medications that suppress the immune system, such as long-term use of glucocorticoids or other specific drugs.
    • Certain types of cancer like aggressive lymphomas, acute leukemia, and others.
    • Having had a stem cell or bone marrow transplant.
    • Having had an organ transplant or being on the waiting list for one.
    • Must be willing and able to follow the study requirements as explained in the informed consent form.
    • Must be enrolled in or a beneficiary of a Social Security program (State Medical Aid is not included).
    • Must have the signature of the participant or their legal representative on the informed consent form.

Who cannot join the trial?

3 criteria

  • Patients who are not diagnosed with Covid-19 cannot participate.
  • Patients who are not within the specified age range cannot participate. The age range includes young adults, adults, and older adults.
  • Patients who are part of a vulnerable population cannot participate. A vulnerable population includes groups that may have a higher risk of harm or exploitation.
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Investigated drugs

  • Nirmatrelvir

    is an antiviral medication used to treat COVID-19. It works by stopping the virus from multiplying in the body, which helps to reduce the severity of the infection. In this trial, researchers are testing whether using nirmatrelvir for a longer period can improve its effectiveness in reducing the presence of the virus in patients who have weakened immune systems.

  • Remdesivir

    is another antiviral drug that is used to treat COVID-19. It helps to prevent the virus from spreading in the body by interfering with its ability to replicate. In this study, remdesivir is being used in combination with nirmatrelvir to see if the two drugs together can more effectively reduce the amount of virus in the body of patients with compromised immune systems.

What is already known about the treatment

  • Nirmatrelvir

    Nirmatrelvir is taken orally and is part of a combination therapy being studied for its effectiveness in treating COVID-19, particularly in patients with weakened immune systems. It is currently being evaluated in clinical trials to determine if extending its use from 5 to 10 days can better reduce the presence of the virus. Nirmatrelvir works by inhibiting a key enzyme that the virus needs to replicate, thus slowing down the infection. It is classified as a direct-acting antiviral (DAA) medication.

  • Remdesivir

    Remdesivir is administered intravenously and is also being studied in combination with nirmatrelvir for treating COVID-19 in immunocompromised patients. This medication is already known in medical literature for its use against COVID-19 and is being further evaluated for its potential to enhance viral clearance when used with other antivirals. Remdesivir works by interfering with the virus's ability to replicate its genetic material, thereby hindering its spread. It is classified as an antiviral medication.

Investigated diseases

COVID-19 – COVID-19 is an infectious disease caused by the SARS-CoV-2 virus. It primarily affects the respiratory system, leading to symptoms such as fever, cough, and difficulty breathing. The disease can progress to more severe respiratory issues, including pneumonia and acute respiratory distress syndrome. In some cases, it may also affect other organs, leading to complications such as blood clots and heart problems. The progression of the disease varies widely among individuals, with some experiencing mild symptoms and others developing severe illness. The virus spreads mainly through respiratory droplets from coughs, sneezes, or talking.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2022-501408-81-01Protocol codeANRS0176s OPTICOVEstimated enrolment423 patientsSponsorInstitut National De La Sante Et De La Recherche Medicale

sourced from the EU Clinical Trials Register and site verification

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