HOVILPRI^® (pritelivir) tablets Frequently asked questions

Although rare in immunocompetent individuals, refractory HSV infection occurs predominantly in immunocompromised patients, including patients receiving treatment for blood cancers, recipients of a hematopoietic cell transplant (HCT) or solid organ transplant (SOT), people living with HIV, and patients receiving immunosuppressive therapy for autoimmune diseases. These immunocompromised adults can have more severe and persistent disease, higher rates of recurrence, and a higher risk of refractory and/or resistant infections.^1-6

Refractory HSV infection should be diagnosed upon failure of a patient's HSV lesions to improve after initial treatment with appropriate antiviral therapy. When it comes to HSV resistance, genotypic and phenotypic testing can confirm acyclovir resistance. However, limited availability and potentially extensive turnaround times may delay results.^6-9

HOVILPRI is indicated in immunocompromised adults for the treatment of mucocutaneous lesions caused by herpes simplex virus (HSV) infection that is refractory (with or without documented resistance) to treatment with acyclovir, valacyclovir, or famciclovir.¹⁰

No. Resistance testing is not required. HOVILPRI is indicated for immunocompromised adults with refractory (with or without documented resistance) HSV infection, which is defined by an inadequate clinical response to appropriate nucleoside analogue treatment. Because genotypic and phenotypic resistance testing may have limited availability and results can take several days, adjustments in clinical management should not be delayed when refractory HSV infections are diagnosed and timely treatment is crucial.^6,8-10

Efficacy and safety were evaluated in 101 immunocompromised adults with refractory HSV infection in a randomized, open-label, comparator-controlled, superiority trial. Patients were randomized 1:1 to¹⁰:

• HOVILPRI (n=51): 400-mg loading dose on Day 1, then 100 mg once daily
• Investigator’s choice (n=50): Intravenous (IV) foscarnet, IV cidofovir, topical cidofovir, or 5% topical imiquimod

Treatment continued for up to 28 days and could be extended up to 42 days for improving mucocutaneous lesions. Refractory HSV was defined as no clinical improvement after ≥7 days of standard-of-care nucleoside analogue therapy, with or without laboratory-confirmed resistance.¹⁰ Key study findings included:

• Nearly 2× complete lesion healing rate (63% with HOVILPRI vs 34% with investigator’s choice up to 28 days)¹⁰
• Demonstrated safety profile

  - The adverse reaction (all grades) occurring in more than 5% of participants was headache, which occurred in 6% and 4% of the patients who received HOVILPRI and investigator’s choice, respectively¹⁰

  - A lower rate of drug-related treatment-emergent adverse events (TEAEs) was reported in participants who were treated with HOVILPRI (22%) compared with participants who were treated with investigator’s choice (54%).
  Discontinuations due to drug-related TEAEs occurred in 2% and 20% of participants, respectively¹⁰

HOVILPRI targets HSV through a novel mechanism designed to overcome common resistance pathways.^6,10,12,13

• Targets the HSV helicase–primase complex, an enzyme essential for HSV DNA replication^6,10
• Does not rely on viral thymidine kinase activation and maintains antiviral activity independent of this pathway¹⁰
• Demonstrated in vitro activity against HSV-1 and HSV-2 isolates, including strains resistant to nucleoside and nucleotide analogues and foscarnet^10,13,14

HOVILPRI offers once-daily oral dosing. Initiate treatment with a loading dose of 400 mg (four 100-mg tablets) on Day 1, followed by a maintenance dose of 100 mg (1 tablet) daily by mouth, with or without food, until HSV lesions have healed.¹⁰

No dose adjustment is required for patients with mild, moderate, or severe renal impairment. Patients with end-stage renal disease or those requiring hemodialysis have not been assessed.¹⁰

HOVILPRI does not require inpatient administration. HOVILPRI is a once-daily oral antiviral that can be administered in both inpatient and outpatient settings.^10,11