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A Study of Doravirine for Early Treatment of West Nile Virus Infection in Patients at Risk of Disease Worsening

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 studying West Nile Virus Infection, which is an illness caused by a virus that is typically spread through mosquito bites. In some people, this infection can lead to more serious complications, particularly in those who have certain risk factors. The treatment being tested in this study is doravirine, which is given as film-coated tablets taken by mouth. Some participants will receive doravirine while others will receive standard care, which means the usual treatment approach currently used for this condition.

The purpose of this study is to find out whether doravirine can help reduce the amount of virus in the blood more quickly in people who have West Nile Virus infection and are at risk of the disease getting worse. The study will look at how fast the virus levels drop in patients who take doravirine compared to those who receive standard care. The study will also examine whether doravirine helps fever go away more quickly.

Participants in this study will be assigned randomly to either receive doravirine or standard care. Those taking doravirine will take 100 milligrams once daily for up to five days. During the study, blood tests will be done to measure the virus levels in the blood. The study is designed to test whether this medication can help prevent the infection from progressing to more serious forms of the disease in people who are at higher risk.

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

    Initial enrollment and treatment assignment

    After your diagnosis of West Nile Virus infection has been confirmed and you have signed the informed consent form, you will be randomly assigned to one of two treatment groups.

    One group will receive doravirine, which is the medication being studied. The other group will receive standard care treatment.

    The random assignment means that neither you nor your doctor will choose which treatment group you will be in. This is determined by chance, similar to flipping a coin.

  2. Step 2

    Treatment period

    If you are assigned to the doravirine group, you will receive Pifeltro 100 mg film-coated tablets to take by mouth.

    The medication is taken orally, meaning you will swallow the tablets.

    The specific dosage schedule, frequency of taking the medication, and total duration of treatment will be provided to you by the study staff based on the study protocol.

  3. Step 3

    Monitoring and assessment

    During the study, your blood will be tested to measure the level of West Nile Virus in your bloodstream. This is called viremia, which means the presence of virus in the blood.

    The main goal is to see how quickly the virus level in your blood decreases by four times compared to the starting level.

    Your body temperature will also be monitored to track how quickly your fever resolves.

    These assessments will help determine whether the medication is effective in treating the infection.

  4. Step 4

    Follow-up observations

    You will continue to be monitored throughout the study period to track your recovery and any changes in your condition.

    The study team will observe whether the treatment helps prevent the infection from progressing to more serious complications affecting the nervous system.

    Regular check-ups will be scheduled to ensure your safety and to collect information about how the treatment is working.

Who can join the trial?

4 criteria

  • You must be 18 years of age or older
  • You must have a confirmed diagnosis of West Nile Virus infection, which means that laboratory tests have proven that you are infected with this virus
  • You must have at least one risk factor for progression to WNND, which means you have certain conditions or characteristics that increase your chance of developing a more serious form of the disease called West Nile neuroinvasive disease, where the virus affects your brain or nervous system
  • You must have signed an informed consent form, which means you have received information about the study and agreed in writing to participate

Who cannot join the trial?

10 criteria

  • Pregnant women - women who are expecting a baby cannot participate in this study
  • Breastfeeding women - women who are nursing a baby cannot participate in this study
  • People with severe liver disease - this means serious problems with how the liver works
  • People with severe kidney disease - this means serious problems with how the kidneys filter waste from the blood
  • People taking certain medications that may interact with the study drug - some medicines do not work well together and can cause harmful effects
  • People with known allergy to doravirine or similar medications - this means the body has a bad reaction to this type of medicine
  • People who cannot swallow pills or tablets
  • People with active cancer requiring treatment - this means cancer that is currently being treated with chemotherapy or other therapies
  • People with uncontrolled seizures - this means repeated episodes where the brain sends abnormal signals causing shaking or loss of consciousness that are not controlled by medication
  • People who are unable to follow study requirements or attend regular visits
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Investigated drugs

Doravirine is an antiviral medication that is being tested in this trial to treat West Nile Virus infection. The study is examining whether this medicine can help reduce the amount of virus in the blood more quickly in patients who are at risk of their infection getting worse.

What is already known about the treatment

Doravirine – Doravirine is an antiviral medication that is taken by mouth as a tablet and is being studied in this clinical trial for the treatment of West Nile Virus infection in patients who are at risk of the disease getting worse. Currently, doravirine is approved for treating HIV infection, but researchers are testing whether it can also help fight West Nile Virus by blocking a specific protein that the virus needs to multiply inside the body's cells. This medication belongs to a class of drugs called non-nucleoside reverse transcriptase inhibitors, which work by interfering with the virus's ability to copy its genetic material and spread to other cells.

Investigated diseases

West Nile Virus Infection – West Nile Virus Infection is a disease caused by a virus transmitted to humans primarily through mosquito bites. The virus enters the bloodstream after a mosquito bite and begins to multiply in the body. Most people infected with the virus do not develop any symptoms or experience only mild flu-like symptoms such as fever, headache, body aches, and fatigue. In some cases, the infection can progress to affect the nervous system, leading to inflammation of the brain or surrounding tissues. This progression may cause more severe symptoms including high fever, neck stiffness, confusion, muscle weakness, and problems with coordination. Certain individuals with specific risk factors are more likely to experience disease progression and develop complications.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2025-521677-14-00Protocol codeDORICOEstimated enrolment50 patientsSponsorAzienda Socio Sanitaria Territoriale Degli Spedali Civili Di Brescia

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