Name: Hovilpri (pritelivir) in Refractory mucocutaneous herpes simplex virus infection in immunocompromised adults: Long-term morbidity
Published: 2026-10-11T11:04:25-04:00

Outcomes associated with refractory or resistant infection after transplantation

“Refractory and/or resistant HSV infections in HCT recipients were associated with poor outcomes, such as recurrent infections, prolonged antiviral therapy, renal injury, higher hospitalization risk, and even death” (opens the source at this quote in a new tab)

“In summary, patients with breakthrough HSV infections with acyclovir-resistant strains after HCT may have extensive and severe mucocutaneous disease that requires prolonged therapy.” (opens the source at this quote in a new tab)
“Complications associated with the need for prolonged antiviral therapy, including hospitalization and renal failure, were common” (opens the source at this quote in a new tab)

Chronic non-healing lesions

“Acyclovir-resistant herpes simplex virus is uncommon but clinically significant, particularly in immunocompromised patients, in whom delayed recognition can lead to chronic nonhealing ulceration and disseminated disease.” (opens the source at this quote in a new tab)

“Despite prolonged courses of foscarnet or cidofovir, with long hospital stays, only half of the patients presented here had clearance of HSV viremia, and none achieved complete healing of the mucocutaneous lesions.” (opens the source at this quote in a new tab)

“Several alternative therapies were introduced, including topical cidofovir and imiquimod, prolonged VACV therapy (6 weeks), and pritelivir. However, all treatment attempts resulted in only partial clinical responses, and the herpetic lesions persisted.” (opens the source at this quote in a new tab)

“Durable control was observed with HSV DNA polymerase inhibitors in only 2 cases, and the immunomodulators imiquimod and thalidomide allowed 5 patients to reach sustained complete response.” (opens the source at this quote in a new tab)

Recurrent episodes over long-term follow-up in people with HIV

“Among 5295 HIV-infected patients, 13 (0.2%) were once diagnosed with an acyclovir-resistant HSV infection.” (opens the source at this quote in a new tab)
“Initially, 11 patients were treated with foscarnet and two with cidofovir. The median follow-up was 67 months (6-145). All patients recurred, 10 presenting at least one acyclovir-resistant HSV recurrence. The median number of acyclovir-resistant HSV recurrences per patient was 2 (0 - 5).” (opens the source at this quote in a new tab)
“Regarding the first and second recurrences, 7/13 (54%) and 5/11 (45%) HSV clinical isolates exhibited resistance to acyclovir, respectively.” (opens the source at this quote in a new tab)

“MCT HSV lesions recurrence after treatment was reported in 33.96 % (18/53, missing 57) patients.” (opens the source at this quote in a new tab)

“Initial episodes were treated with VACV, followed by FOS due to multiple recurrences and the identification of an ACV resistant–associated mutation during the third recurrence.” (opens the source at this quote in a new tab)

Renal injury from second-line antiviral therapy

“acute kidney injury secondary to antivirals in nine (50%) patients, and hemodialysis subsequent to kidney injury in four (22%) patients.” (opens the source at this quote in a new tab)

“Among 109 foscarnet courses, ≥1 toxicity was reported during 75 courses (68.8%). Discontinuation because of toxicity was reported in 33 (30.3%) courses. The most common toxicity or intolerance was renal function abnormalities reported during 44 courses (40.4%), followed by electrolyte abnormalities and gastrointestinal symptoms (nausea and anorexia).” (opens the source at this quote in a new tab)
“Among 6 IV cidofovir courses, renal function abnormalities were reported during 3 courses (50%). One of 6 courses of IV cidofovir was discontinued because of the renal function abnormalities.” (opens the source at this quote in a new tab)

“Foscarnet was discontinued in 10 episodes (32%) due to an adverse event including in 6 episodes (19%) due to kidney disorders.” (opens the source at this quote in a new tab)
“Two episodes of HSV that were complicated by serious adverse events were due to acute kidney injury, 1 of which led to foscarnet discontinuation.” (opens the source at this quote in a new tab)

“Two patients (40%) developed acute renal failure related to antiviral therapy requiring dose adjustments for creatinine clearance, and electrolyte disturbances were common (80%)” (opens the source at this quote in a new tab)

Prolonged hospitalization and deconditioning

“Furthermore, foscarnet therapy given over adequate durations to treat resistant HSV typically requires careful management in the inpatient setting that can lead to prolonged hospitalization. The cumulative effect of both antiviral and concomitant medication toxicities, coupled with deconditioning resulting from prolonged hospitalization, can make foscarnet therapy difficult to recover from in this morbid patient population.” (opens the source at this quote in a new tab)
“We were also not able to collect retrospective data describing common clinically observed potential downstream effects of foscarnet therapy such as volume overload and substantial peripheral edema resulting from the large volume of fluid and electrolyte repletion typically given with the drug.” (opens the source at this quote in a new tab)

Emergence of foscarnet resistance after foscarnet exposure

“Four patients had laboratory-confirmed foscarnet resistance, by phenotypic assays. In 3 of the 4 patients, foscarnet resistance testing was performed after a median of 25 days (minimum, maximum: 20, 37) of foscarnet therapy.” (opens the source at this quote in a new tab)

“Six patients displayed foscarnet resistance, with an MIC (minimum inhibitory concentration) of >200 μg/mL, and these patients had been exposed to foscarnet within the previous month.” (opens the source at this quote in a new tab)

Scarring

No evidence found.

Delay of chemotherapy or transplantation attributable to refractory infection

No evidence found.