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Study on Pritelivir for Treating Acyclovir-Resistant Herpes Simplex Virus in Immunocompromised 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 the treatment of acyclovir-resistant mucocutaneous herpes simplex virus (HSV) infections in individuals with weakened immune systems. The trial will evaluate the effectiveness and safety of a medication called pritelivir, which is taken orally in the form of a tablet. The study will also involve other treatments, including Foscavir (foscarnet sodium hexahydrate), Imiquimod cream, and anhydrous cidofovir, which are used in different forms such as infusions or topical applications.

The purpose of the study is to assess how well pritelivir works in treating these specific HSV infections compared to other treatments chosen by the investigator. Participants will receive treatment for a maximum of 28 days, and the study will monitor the healing of lesions, the recurrence of the virus, and any side effects experienced by the participants. The trial will also look at how quickly the lesions heal and how long it takes for any pain associated with the lesions to stop.

Throughout the study, participants will be closely monitored by healthcare professionals to ensure their safety and to gather data on the effectiveness of the treatments. The trial aims to provide valuable information on the best ways to manage acyclovir-resistant HSV infections in people with compromised immune systems, potentially leading to improved treatment options in the future.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the trial

    Upon joining the trial, the participant will be informed about the study's purpose and procedures. Consent will be obtained to ensure understanding and agreement to participate.

  2. Step 2

    Treatment initiation

    The participant will begin treatment with oral pritelivir at a dosage of 100 mg once a day. This treatment is intended for those with acyclovir-resistant mucocutaneous HSV infections.

    The treatment period is set for a maximum of 28 days. The participant will be monitored for any side effects or reactions to the medication.

  3. Step 3

    Monitoring and assessment

    Throughout the treatment, the participant's condition will be regularly assessed. This includes checking for healing of lesions and any new symptoms.

    The participant will report any pain experienced at the lesion site, and the time taken for pain to cease will be recorded.

  4. Step 4

    Completion of treatment

    At the end of the 28-day treatment period, the participant's response to the medication will be evaluated. This includes assessing the healing of lesions and any recurrence of symptoms.

    The participant will be asked to continue reporting any symptoms or side effects for a specified period after the treatment ends.

  5. Step 5

    Follow-up

    Follow-up assessments will occur at 1, 2, and 3 months after the end of treatment to monitor for any recurrence of HSV infections.

    The participant's overall health and any long-term effects of the treatment will be evaluated during these follow-up visits.

Who can join the trial?

8 criteria

  • Participants must be immunocompromised. This means their immune system is weaker than normal due to conditions like HIV infection, organ transplants, or long-term use of medications that suppress the immune system.
  • Participants must be at least 16 years old. In some countries, like Canada, Germany, and Belgium, they must be at least 18 years old.
  • Participants must have a type of herpes infection that does not respond to a common treatment called acyclovir. This is known as acyclovir-resistant infection.
  • The herpes sores must be in a place where they can be easily seen and checked by a doctor.
  • Participants must agree to use highly effective birth control methods to prevent pregnancy during the study and for a certain time after the study ends. This applies to both men and women.
  • Participants must be able to understand and agree to the study's consent form, or have a legal representative who can do so on their behalf.
  • Women who can become pregnant must have a negative pregnancy test before starting the study and on the first day of the study.
  • Participants must provide written consent to join the study. If they cannot do this themselves, a legal representative must provide consent for them.

Who cannot join the trial?

5 criteria

  • Patients who are not immunocompromised. Being immunocompromised means having a weakened immune system, which makes it harder for the body to fight infections.
  • Patients who do not have acyclovir-resistant mucocutaneous HSV infections. Acyclovir-resistant means that the herpes virus does not respond to the usual treatment with the drug acyclovir.
  • Patients who are not intolerant to foscarnet. Foscarnet is another medication used to treat herpes infections, and being intolerant means having adverse reactions to it.
  • Patients who are not within the specified age range for the study.
  • Patients who do not meet other specific health criteria set by the study.
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Investigated drugs

  • Pritelivir

    is an oral medication being studied for its effectiveness in treating herpes simplex virus (HSV) infections that are resistant to the commonly used antiviral medication, acyclovir. This trial is particularly focused on patients who have weakened immune systems and are dealing with these resistant infections. The study aims to determine how well pritelivir works over a treatment period of up to 28 days.

  • Acyclovir

    is a standard antiviral medication used to treat infections caused by the herpes simplex virus. In this trial, it serves as a comparison to pritelivir, especially in cases where the virus has become resistant to acyclovir. The goal is to see if pritelivir can be a more effective treatment option for these resistant infections.

  • Foscarnet

    is another antiviral medication that is sometimes used when acyclovir is not effective. In this trial, pritelivir is being tested for its ability to treat infections that are resistant to both acyclovir and foscarnet, or when patients cannot tolerate foscarnet. The study aims to assess the safety and effectiveness of pritelivir in these challenging cases.

What is already known about the treatment

Pritelivir – Pritelivir is administered orally in the form of tablets, taken once a day. It is currently being studied in clinical trials for its effectiveness and safety in treating acyclovir-resistant mucocutaneous herpes simplex virus (HSV) infections, particularly in individuals with weakened immune systems. The main therapeutic indication for pritelivir is the treatment of HSV infections that do not respond to standard antiviral medications like acyclovir. At the molecular level, pritelivir works by inhibiting the helicase-primase enzyme complex, which is essential for viral DNA replication, thereby preventing the virus from multiplying. It is classified pharmacologically as an antiviral agent.

Investigated diseases

Acyclovir-resistant mucocutaneous herpes simplex virus infections in immunocompromised individuals – This condition occurs when the herpes simplex virus (HSV) infects the skin and mucous membranes, and the virus is resistant to the antiviral medication acyclovir. It primarily affects individuals with weakened immune systems, making it difficult for their bodies to control the infection. The disease is characterized by the appearance of painful blisters or sores on the skin or mucous membranes, which can be persistent and difficult to heal. Over time, these lesions may spread or worsen, especially if the immune system remains compromised. The resistance to acyclovir complicates treatment, as the usual antiviral therapy is ineffective, requiring alternative approaches. The progression of the disease can vary, with some individuals experiencing recurrent outbreaks.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-510088-37-00Protocol codeAIC316-03-II-01Estimated enrolment152 patientsSponsorAiCuris Anti-infective Cures AG

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