Home › Trials › NCT03073967

Treatment of Acyclovir-resistant HSV Infections in Immunocompromised Patients

A Randomized, Open Label, Multi-center, Comparative Trial, to Assess the Efficacy and Safety of Pritelivir for the Treatment of Acyclovir-resistant Mucocutaneous HSV (Herpes Simplex Virus) Infections in Immunocompromised Subjects (PRIOH-1)

Phase 3 Interventional AiCuris Anti-infective Cures AG · NCT03073967

This study is testing if pritelivir tablets can effectively treat herpes infections that don't respond to acyclovir in people with weakened immune systems.

Quick facts

PhasePhase 3
Study typeInterventional
Enrollment153 (estimated)
Ages16 Years and up
SexAll
SponsorAiCuris Anti-infective Cures AG Industry-sponsored
Locations64 sites (Birmingham, Alabama and 63 other locations)
Trial IDNCT03073967 on ClinicalTrials.gov

What this trial studies

This clinical trial evaluates the efficacy and safety of pritelivir tablets in treating mucocutaneous herpes simplex virus (HSV) infections that are resistant to acyclovir in immunocompromised individuals. Participants will receive either pritelivir or an investigator's choice of alternative treatments, including foscarnet or cidofovir. The trial is structured in multiple parts, with a focus on demonstrating the superiority of pritelivir in achieving clinical cure within 28 days. The study aims to provide a new treatment option for patients who have limited responses to existing therapies.

Who should consider this trial

Good fit: Ideal candidates include immunocompromised individuals aged 16 years and older with confirmed acyclovir-resistant mucocutaneous HSV infections.

Not a fit: Patients who are not immunocompromised or those without acyclovir-resistant HSV infections may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could offer a new effective option for patients suffering from acyclovir-resistant HSV infections.

How similar studies have performed: Previous studies have shown promise in treating acyclovir-resistant HSV infections, but this specific approach with pritelivir is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria 
Part C inclusion criteria

1. Immunocompromised men and women of any ethnic group aged ≥16 years.

   In Canada, Germany, Belgium:

   Immunocompromised (due to conditions including but not limited to HIV infection, hematopoietic cell or solid organ transplantation, and chronic use of immunosuppressive treatment) men and women of any ethnic group aged \>18 years.
2. ACV-R mucocutaneous HSV infection based on clinical failure or positive genotypic/phenotypic ACV resistance testing for current lesion. Clinical failure is defined as no improvement after oral or iv doses for at least 7 days at doses equivalent to or greater than the local agency approved high oral doses of acyclovir, valacyclovir or famciclovir.
3. Lesions accessible for visual inspection to allow assessment of lesion healing including visualization by endoscopy.
4. Willingness to use highly effective birth control.
5. Subject, and/or their legally authorized representative, (proxy consent is not permitted in Germany), must be willing and able to understand the Informed Consent Form.
6. Negative serum β-HCG (beta-human chorionic gonadotropin) test for women of child-bearing potential at Screening and a negative urine pregnancy test at Day 1.
7. Written informed consent. For subjects, who are unable to provide informed consent for whatever reason, written consent must be obtained from the legal representative, (proxy consent is not permitted in Germany).

Part D and F inclusion criteria

All inclusion criteria as for Part C, except for inclusion criterion 2, which is replaced by:

2. ACV-R and foscarnet-R mucocutaneous HSV infection based on clinical failure or positive genotypic/phenotypic resistance testing for current lesion or documented intolerance to iv foscarnet requiring cessation of foscarnet treatment or precluding foscarnet treatment.

Subjects will be able to enter Part F only after closure of enrollment in Part D.

Part E inclusion (Part E is not being conducted in Germany)

All inclusion criteria as for Part C, except for inclusion criterion 2, which is replaced by:

2. Recurrent mucocutaneous HSV infection considered ACV-S.

Part C exclusion criteria

1. Known resistance/intolerance to pritelivir or any of the excipients.
2. Previous treatment in PRIOH-1.
3. Baseline safety laboratory abnormalities.
4. History or current evidence of gastrointestinal malabsorption which, in the opinion of the Investigator, may affect the extent of absorption of pritelivir.
5. Hemodialysis for any indication and ESRD (eGFR \<15 mL/min; stage 5 CKD)
6. History or current evidence of significant cardiovascular, pulmonary, hepatic, renal, gastrointestinal, hematological, endocrinological, metabolic, neurological, psychiatric, or other relevant diseases.
7. Abnormalities in hematological, clinical chemical or any other laboratory variables.
8. Not able to communicate meaningfully with the Investigator and site staff.
9. Any other condition which in the opinion of the Investigator would interfere with successful completion of this clinical trial.
10. Any other important local condition.
11. Pregnant and/or breastfeeding women.
12. Having received an investigational drug in an investigational drug trial unter certain conditions.

    Part D (complete) exclusion criteria

    All exclusion criteria as for Part C, except criterion 12, which is replaced by:
13. Having received an investigational drug in an investigational trial within 7 half-lives after the last administration of this drug before initiating trial medication, except for subjects entering Part D, who have previously received foscarnet treatment in Part C of this trial.

Participation in a clinical trial without receiving other investigational drugs (eg, follow-up phase of a trial, observational study) is permitted.

Part E exclusion criteria (Part E is not being conducted in Germany)

All exclusion criteria in Part E are identical to those in Part C with the addition of:

13. Having used acyclovir, valacyclovir, or famciclovir within 3 days prior to starting pritelivir.

Part F exclusion criteria All exclusion criteria for Part D plus 13. Part D open for enrollment

Where this trial is running

Birmingham, Alabama and 63 other locations

+14 more sites — see ClinicalTrials.gov for the full list.

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
View on ClinicalTrials.gov → Find more trials like this →
Conditions HSV Infection
Last reviewed 2026-06-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.