Purpose of the expanded access protocol

“The purpose of the expanded access program (EAP) is to provide pritelivir to immunocompromised subjects with treatment resistant HSV type 1 or 2 who cannot participate in a clinical trial and for whom no approved treatment option is available.” (opens the source at this quote in a new tab)
“In view of the available pre-clinical and clinical data for pritelivir in immunocompromised subjects with treatment resistant HSV, the lack of treatment options, and the demand for compassionate use of pritelivir, AiCuris aims to provide access to pritelivir via this expanded access program (intermediate size treatment protocol) in the USA.” (opens the source at this quote in a new tab)
“This EAP enables pritelivir to be available as a treatment option for immunocompromised subjects with treatment-resistant HSV type 1 or 2, who do not have access to clinical trial options.” (opens the source at this quote in a new tab)

Purpose of the early access program run with myTomorrows

“Aicuris supports expanded access requests for the treatment of eligible patients outside of the Phase 3 clinical trial and collaborates with myTomorrows to facilitate early access to pritelivir for acyclovir-refractory mucocutaneous HSV infections in immunocompromised patients.” (opens the source at this quote in a new tab)

“In collaboration with myTomorrows, AiCuris provides a potential pathway to access Pritelivir oral tablets for the treatment of active Herpes Simplex Virus (HSV) mucocutaneous infections that are refractory, with or without resistance, to both acyclovir and foscarnet, in immunocompromised patients.” (opens the source at this quote in a new tab)

Purpose stated when the early access program was announced

“AiCuris Anti-infective Cures GmbH, a leading company in the discovery and development of drugs against infectious diseases and myTomorrows, a Netherlands-based HealthTech company facilitating access to medicines in development and real-world data collection, today announced a collaboration to develop an Early Access Program (EAP) for pritelivir, currently undergoing Phase II testing for treatment of acyclovir-resistant mucocutaneous HSV infections in immunocompromised patients.” (opens the source at this quote in a new tab)
“Our collaboration with myTomorrows may help provide patients with an unmet medical need with access in their home country to a potential treatment option.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection: aim of a 2-participant report

“However, there is a paucity of clinical data on pritelivir administration in real life. Herein, we present two cases of acyclovir r/r HSV-1 infections in allogeneic HCTr at our institution.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with genital HSV-2 infection: aim of a 2-participant report

“We present herein two HSCT recipients receiving repeated courses of the novel helicase-primase inhibitor pritelivir for recurrent genital aciclovir-resistant HSV-2 infections.” (opens the source at this quote in a new tab)

Stem cell transplant recipient with HSV-2 infection refractory to second-line therapy: aim of a case report

“We present a case of aciclovir-resistant herpes simplex virus 2 (HSV-2) in an immunosuppressed (HIV negative) allogenic peripheral blood stem cell transplant (SCT) recipient which was refractory to second-line therapy.” (opens the source at this quote in a new tab)

Person living with HIV with orolabial HSV-2 infection: aim of a case report

“Our report describes use of pritelivir, a novel helicase-primase inhibitor, in the treatment of nucleoside analogue–refractory orolabial HSV-2 infection.” (opens the source at this quote in a new tab)

Stem cell transplant recipient given pritelivir for treatment and for secondary prophylaxis: aim of a case report

“This is the first case report of pritelivir used for both treatment and secondary prophylaxis in an allogeneic stem cell transplant recipient with severe, relapsing multidrug-resistant HSV-1, administered through an expanded access programme.” (opens the source at this quote in a new tab)

Herpes simplex encephalitis, a use outside the labeled indication: aim of a case report

“Here, we report the first clinical use of pritelivir after failure of acyclovir and foscarnet in a patient with HSE.” (opens the source at this quote in a new tab)

Pediatric transplant recipients, a use outside the labeled indication: aim of an 8-participant series

“This case series aims to describe the clinical course, associated complications, and treatment course of these patients, including side effects.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipient treated in two episodes: aim of a case study within a review

“Herein, we describe a case study of an allogeneic HCT recipient treated with multiple agents, including pritelivir, within the Expanded Access Program during two episodes of refractory HSV infection.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection and HSV pneumonitis: aim of two cases within a pharmacology review

“In Box 1, we describe two patients from our medical center demonstrating the difficulty of treating viral reactivation in immunocompromised patients.” (opens the source at this quote in a new tab)

Expanded access record: country, protocol number, registration dates, and status

Field	Quoted record
Country	“in the USA”
Other study identifier	“AIC316-03-E-01”
First submitted	“2023-04-25”
First posted	“2023-05-06”
Last update posted	“2025-02-10”
Status	“Available”
Locations	“No location data”

Planned duration of the expanded access protocol

“The program will continue until pritelivir becomes available through other mechanisms, or until Sponsor chooses to discontinue the program.” (opens the source at this quote in a new tab)

Start of the early access program and number of countries

“Over 150 patients worldwide have received pritelivir through the ongoing Early Access Program, initiated in 2020.” (opens the source at this quote in a new tab)

“>65 patients with more than 100 outbreaks treated in 10 countries” (opens the source at this quote in a new tab)

Compassionate use program in Germany

“In December 2020, the "Bundesinstitut für Arzneimittel und Medizinprodukte (BfArM)" acknowledged to initiate a Compassionate Use Program for pritelivir in Germany. This is part of an Early Access Program (EAP) in various countries throughout the world.” (opens the source at this quote in a new tab)

Data cut-off of the sponsor's aggregate early access data

“Status as of Apr 26, 2024.” (opens the source at this quote in a new tab)

Person living with HIV in Canada: access route and treatment date

“At this time, approval was obtained by Health Canada's Special Access Program for pritelivir, and medication was provided through an Early Access Program by myTomorrows on behalf of AiCuris, to whom the drug is licenced. In early 2022, the patient received oral pritelivir, 400 mg once followed by 100 mg daily for 27 days with an excellent clinical response” (opens the source at this quote in a new tab)

Stem cell transplant recipient in the United Kingdom

“We believe this to be the first clinical use of this therapeutic agent in the United Kingdom.” (opens the source at this quote in a new tab)

Pediatric transplant recipients: center and period

“A total of eight patients were identified with acyclovir-resistant HSV at Royal Manchester Children's Hospital between 2012 and 2025.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipient treated in two episodes: transplant dates

“A 59-year-old man with chronic lymphocytic leukaemia/small lymphocytic lymphoma with Richter's transformation underwent matched unrelated donor allogeneic HCT on February 3, 2021.” (opens the source at this quote in a new tab)
“A second allogeneic HCT from a mismatched unrelated donor was performed on February 9, 2024” (opens the source at this quote in a new tab)

Expanded access protocol: design and monitoring

“This is a multicenter EAP (via intermediate size treatment protocol) designed to provide access to pritelivir for eligible immunocompromised subjects that are not responding to the available FDA-approved antiviral options or cannot use these because of an underlying medical condition, and who cannot enter a clinical trial.” (opens the source at this quote in a new tab)
“Each subject considered for the EAP will undergo minimal assessment at baseline for lesion assessment and safety (laboratory tests and general physical evaluation). After eligibility check and starting the treatment, the subjects will be monitored on a weekly basis.” (opens the source at this quote in a new tab)

Expanded access record: type and collaborator

Field	Quoted record
Expanded access type	“Treatment IND/Protocol”
Study type	“Expanded Access”
Collaborator	“Impatients N.V. trading as myTomorrows”

Early access program: request by the treating physician

“To get access, patients need to consult with their treating physician to explore all treatment options. If the physician agrees to a treatment with pritelivir oral tablets and to oversee the patient’s treatment, the physician needs to contact the myTomorrows medical team for more information on the EAP.” (opens the source at this quote in a new tab)

Early access program: individual review of each request

“Each request is reviewed individually, based on the patient’s clinical situation and the program’s eligibility criteria. A detailed medical rationale may be required to assess eligibility.” (opens the source at this quote in a new tab)
“Your request will be reviewed by our team within 1 business day.” (opens the source at this quote in a new tab)

Early access program as defined by the sponsor

“An Early Access Program (EAP), also known as Expanded Access Program or Managed Access Program, supports in a compliant and controlled way the treatment with a medicine currently not licensed in a patient's country of residence. Such treatment can be an option for patients who have high unmet medical need, have exhausted all registered treatment options and cannot participate in a clinical trial.” (opens the source at this quote in a new tab)

Reference to the expanded access program in a federal HIV guideline

“An expanded access program of oral pritelivir is available for immunocompromised people with acyclovir-resistant HSV infection” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection: two cases treated through the expanded access program

“We present two allogeneic hematopoietic cell transplantation recipients (HCTr) treated with pritelivir for acyclovir-resistant/refractory (r/r) HSV infection based on the expanded access program of the pritelivir manufacturer.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with genital HSV-2 infection: resistance genotyping

“UL23, UL30, UL5 and UL52 genes encode HSV-2 TK, DNA polymerase, helicase and primase, respectively, and were sequenced as previously described.” (opens the source at this quote in a new tab)

Pediatric transplant recipients: retrospective case series with genotypic resistance testing

“A retrospective case series of eight pediatric patients with acyclovir-resistant HSV infection, determined via genotypic sequencing, post allogeneic HSCT between 2012 and 2025.” (opens the source at this quote in a new tab)
“Acyclovir resistance was determined using genotypic nucleotide sequencing following polymerase chain reaction (PCR) amplification of gene targets.” (opens the source at this quote in a new tab)

Herpes simplex encephalitis: retrospective report of an individual treatment attempt

“This retrospective case report describes the use of Pritelivir as an individual treatment attempt for a critically ill patient with refractory herpes simplex encephalitis. The use of Pritelivir in the Early Access Program was conducted in accordance with applicable national regulations governing compassionate use of investigational medicinal products and did not require separate ethics committee approval under the relevant legal framework.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipient treated in two episodes: case selected for a review

“We chose an HCT recipient with a complicated refractory HSV infection as a representative clinical case.” (opens the source at this quote in a new tab)

Review table of published expanded access cases in transplant recipients

“depicts previously published data for HCT recipients with R/R HSV infections treated with pritelivir in the Expanded Access Program” (opens the source at this quote in a new tab)

Expanded access protocol: population

“The patient population is focused on those immunocompromised subjects that are not responding to the available FDA-approved antiviral options or cannot use these because of an underlying medical condition.” (opens the source at this quote in a new tab)

Expanded access protocol: main inclusion criteria

Criterion	Quoted record
Immune status and age	“Immunocompromised (due to conditions including but not limited to HIV infection, hematopoietic-cell or solid organ transplantation, and chronic use of immunosupressive treatment) men and women of any ethnic group aged ≥16 years.”
Infection	“ACV-resistant and foscarnet-resistant/intolerant mucocutaneous HSV infection based on clinical failure (no improvement after oral or iv doses for at least 7 days at doses equivalent to or greater than the local agency approved high doses of valacyclovir or famciclovir and/or foscarnet iv therapy or intolerance to foscarnet requiring cessation of foscarnet treatment) or result from genotypic/phenotypic testing or ACV-resistant and previously treated in PRIOH-1 Part C.”
Virologic confirmation	“The current lesion(s) should be confirmed to be positive for HSV before the start of treatment. If not tested beforehand, a lesion swab should be taken for PCR or cell culture before starting treatment, but treatment may be started before obtaining results.”
Lesion	“Visual confirmation of lesion at start of treatment (including by endoscopy).”
Contraception	“Willing to remain abstinent or use highly effective method of contraception.”
Pregnancy testing	“Negative pregnancy test for females of childbearing potential at Day 1 and every 4 weeks thereafter.”
Consent	“Patient must be willing and able (in the opinion of the physician) to understand the informed consent form. Patient must give written informed consent.”
Ages eligible	“16 Years and older (Child, Adult, Older Adult)”

Expanded access protocol: main exclusion criteria

Criterion	Quoted record
Access to a trial	“Eligibility and feasibility for a patient to participate in a currently ongoing clinical trial with pritelivir.”
Intolerance	“Known intolerance to pritelivir or any of the excipients (microcrystalline cellulose, croscarmellose sodium, mannitol, colloidal anhydrous silica, magnesium stearate, hydroxy propyl methyl cellulose, polyethylene glycol, calcium diphosphate).”
Proton pump inhibitors excluded at any dose	“Need to use the following medications at any dose: esomeprazole, rabeprazole.”
Proton pump inhibitors excluded above a daily dose	“Need to use the medications with the following daily dose levels: omeprazole > 20 mg/d, lansoprazole > 20 mg/d or pantoprazole > 80 mg/d.”
Absolute neutrophil count	“ANC < 1000 cells/mm3”
Platelets	“Platelet count < 25,000 cells/mm3”
Hemoglobin	“Hemoglobin < 8.0 g/dL”
Aminotransferases	“AST or ALT > 5 x ULN”
Bilirubin	“Bilirubin > 2.5 x ULN”
Malabsorption	“History or current evidence of gastrointestinal malabsorption which, in the opinion of the physician, may affect the extent of absorption of pritelivir.”
Renal function	“Hemodialysis for any indication and ESRD (eGFR <15 mL/min; stage 5 CKD).”
Other disease	“History or current evidence of significant cardiovascular, pulmonary, hepatic, renal, gastrointestinal, hematological, endocrinological, metabolic, neurological, psychiatric, or other diseases, which, in the opinion of the physician, may affect the patient's safety.”
Laboratory abnormalities	“Abnormalities in hematological, clinical chemical or any other laboratory variables regarded as clinically relevant by the physician unless they are due to underlying disease or condition.”
Pregnancy and breastfeeding	“Pregnant and/or breastfeeding women.”

Early access program: eligible population as described by the sponsor

“Eligible patients for an EAP are in high medical need, cannot participate in a clinical trial, and have exhausted all registered treatment options.” (opens the source at this quote in a new tab)

Early access program: primary focus stated in a congress poster

“Primary focus is immunocompromised patients suffering from acyclovir-refractory/resistant HSV infections, particularly those who are also resistant or intolerant to foscarnet.” (opens the source at this quote in a new tab)

Early access program: population as described in a published case report

“Pritelivir is accessible through an early access program (EAP) for immunocompromised patients with acyclovir-refractory or resistant infections that are also foscarnet-refractory or intolerant” (opens the source at this quote in a new tab)

Pediatric transplant recipients: inclusion in the case series

“Patients were eligible for inclusion if they had either primary HSV infection or HSV reactivation.” (opens the source at this quote in a new tab)

Expanded access protocol: pritelivir regimen

“Participants receive a loading dose of 400 mg (4 x 100 mg tablet) pritelivir on first day followed by continuous dose of 100 mg per day.” (opens the source at this quote in a new tab)

Expanded access program: regimen and extension to 42 days as described in a published report

“Pritelivir was obtained through the Expanded Access Program supported by AiCuris [loading dose of 400 mg on Day 1, then 100 mg once daily; in the case of a partial response at Day 28, pritelivir can be administered for an additional 14 days (maximum total treatment duration = 42 days)].” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with genital HSV-2 infection: five pritelivir courses in 2 participants

Pritelivir course	Days of treatment	Symptoms	Tolerance of antiviral treatment
Participant 1, first course	“Day 41–83”	“almost complete healing”	“good”
Participant 1, second course	“Day 149–191”	“complete healing”	“good”
Participant 1, third course	“Day 248–290”	“complete healing”	“good”
Participant 2, first course	“Day 140–168”	“complete healing”	“good”
Participant 2, second course	“Day 348–ongoing”	“complete healing”	“good”

Hematopoietic cell transplant recipients with oral HSV-1 infection: regimen and duration in 2 participants

“As pritelivir was already at the hospital pharmacy, therapy with pritelivir 100 mg once daily p.o. was started on PTD 445 until PTD 478” (opens the source at this quote in a new tab)
“Treatment with pritelivir 100 mg once daily p.o. was initiated on PTD 146 after approval by the Expanded Access Program by AiCuris for compassionate use” (opens the source at this quote in a new tab)

Characteristic	Case 1	Case 2
HSV infection diagnosis	“Fifth HSV episode”	“Third HSV episode”
Pritelivir start, posttransplant day	“445”	“146”
Pritelivir end, posttransplant day	“478”	“176”
Treatment duration in total, days	“34”	“30”
Secondary prophylaxis	“None”	“None”

Person living with HIV with orolabial HSV-2 infection: regimen

“The patient was started on oral pritelivir 400 mg once followed by 100 mg daily for 27 days, obtained through Health Canada's Special Access Program, resulting in near complete resolution of the lesion.” (opens the source at this quote in a new tab)

Stem cell transplant recipient with esophagitis: administration through a gastrostomy tube, repeated courses, and secondary prophylaxis

“Finally, rescue therapy with pritelivir was administered through a PEG tube for 42 days.” (opens the source at this quote in a new tab)
“A new 42-day course of pritelivir was administered, leading to clinical remission. The patient started secondary prophylaxis with pritelivir (100 mg/d following loading dose of 400 mg) for 3 months through expanded access approval, and no recurrences were reported.” (opens the source at this quote in a new tab)
“the first lasting 42 days, the second 132 days, and the last 60 days” (opens the source at this quote in a new tab)

Herpes simplex encephalitis, a use outside the labeled indication: pritelivir by nasogastric tube with intravenous acyclovir

“With the consent of the patient’s relative, he received pritelivir 100 mg daily via a nasogastric tube, following a 400 mg loading dose on the first day of treatment, in combination with intravenous acyclovir (2 x 10 mg/kg i.v. per day).” (opens the source at this quote in a new tab)
“Treatment with pritelivir was continued for 30 days.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipient treated in two episodes: two 42-day courses

“On D+104, compassionate treatment with pritelivir was initiated for a 42-day course (400 mg loading dose and 100 mg daily afterwards), resulting in a complete response with no apparent side effects identified.” (opens the source at this quote in a new tab)
“Because of renal failure and the imperilling use of FOS or CDV, compassionate use of pritelivir was initiated for 6 weeks (400 mg loading dose and 100 mg daily afterwards).” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection and HSV pneumonitis: treatment in 2 participants

“Via an Early Access Program, we received pritelivir. After 1 week of treatment her oral ulcerations resolved, and she completed 4 weeks of treatment without significant toxicities. Thereafter valacyclovir prophylaxis was restarted.” (opens the source at this quote in a new tab)
“Here, pritelivir was started via the Early Access Program and both acyclovir and foscarnet were halted.” (opens the source at this quote in a new tab)

Pediatric transplant recipients, a use outside the labeled indication: supply delay and limited duration

“Pritelivir was provided on compassionate access for two cases in our series (Case 1and Case 5), but there was significant delay (> 20 days) between application, approval, and arrival of the drug and its duration of use was limited by the supplier.” (opens the source at this quote in a new tab)

Person living with HIV with anogenital HSV-2 infection: pritelivir among several therapies

“Several alternative therapies were introduced, including topical cidofovir and imiquimod, prolonged VACV therapy (6 weeks), and pritelivir.” (opens the source at this quote in a new tab)

Assessments specified in the expanded access protocol

“Each subject considered for the EAP will undergo minimal assessment at baseline for lesion assessment and safety (laboratory tests and general physical evaluation). After eligibility check and starting the treatment, the subjects will be monitored on a weekly basis.” (opens the source at this quote in a new tab)

Healing categories and handling of unknown outcomes in the sponsor's aggregate data

“healed / partially healed within 28 days” (opens the source at this quote in a new tab)
“healed / partially healed within 42 days” (opens the source at this quote in a new tab)
“10 out of 147 treatment cycles excluded, since not evaluable (no post-baseline information available). "Unknowns" considered as not healed.” (opens the source at this quote in a new tab)

Healing outcome in the earlier interim analysis of the early access program

“evaluable patients with documented healing of lesions” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with genital HSV-2 infection: resistance genotyping as an outcome

“UL23, UL30, UL5 and UL52 genes encode HSV-2 TK, DNA polymerase, helicase and primase, respectively, and were sequenced as previously described.” (opens the source at this quote in a new tab)

Herpes simplex encephalitis: viral load in cerebrospinal fluid as an outcome

“Viral loads (copies/ml) of HSV1 were measured in the cerebrospinal fluid.” (opens the source at this quote in a new tab)

Early access program: participants and countries in the earlier corporate slides

“>65 patients with more than 100 outbreaks treated in 10 countries” (opens the source at this quote in a new tab)

Early access program: participants and evaluable treatment cycles in the later corporate slides

“Early access program with >90 highly immunocompromised patients” (opens the source at this quote in a new tab)
“with acyclovir-resistance & foscarnet-resistance or intolerance” (opens the source at this quote in a new tab)
“Status as of Apr 26, 2024. 10 out of 147 treatment cycles excluded, since not evaluable (no post-baseline information available).” (opens the source at this quote in a new tab)

Early access program: participants worldwide in a congress poster

“Over 150 patients worldwide have received pritelivir through the ongoing Early Access Program, initiated in 2020.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection: 2 participants

“Herein, we present two cases of acyclovir r/r HSV-1 infections in allogeneic HCTr at our institution.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with genital HSV-2 infection: 2 participants

“We present herein two HSCT recipients receiving repeated courses of the novel helicase-primase inhibitor pritelivir for recurrent genital aciclovir-resistant HSV-2 infections.” (opens the source at this quote in a new tab)

Pediatric transplant recipients: 3 pritelivir recipients among 8 participants

“A total of 87.5% of patients (n = 7) were treated with second-line antivirals (foscarnet and/or cidofovir), and three patients were treated with third-line antivirals (pritelivir).” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection and HSV pneumonitis: 2 participants

“Two patient cases illustrating the difficulties of treating HSV in immunocompromised patients” (opens the source at this quote in a new tab)

Early access program: treatment cycles excluded from the sponsor's aggregate data

“10 out of 147 treatment cycles excluded, since not evaluable (no post-baseline information available).” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection: end of follow-up in 2 participants

“Follow-up ended at PTD 743.” (opens the source at this quote in a new tab)
“Follow-up ended at PTD 243.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipient with HSV pneumonitis: death during pritelivir treatment

“Unfortunately, the patient developed an idiopathic lung syndrome and multiorgan failure and died while on pritelivir treatment.” (opens the source at this quote in a new tab)

Herpes simplex encephalitis: discharge and death after treatment

“The patient was discharged to a neurological rehabilitation program. Unfortunately, he died five months later, on day +380 after HCT, due to long-term neurological sequelae.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipient treated in two episodes: death after the second episode

“The patients expired on D+160 secondary to multiple organ failure.” (opens the source at this quote in a new tab)

Stem cell transplant recipient with HSV-2 infection: death as recorded in a review table

“The patient died of hospital-acquired pneumonia.” (opens the source at this quote in a new tab)

Early access program: underlying conditions of treated participants

“Majority are transplant (57%) or HIV-infected (25%) patients” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection: first of 2 participants

“A 35-year-old patient with a history of acute lymphoid leukemia type B (ALL-B) Philadelphia+ received an allogeneic HCT from an unrelated human leukocyte antigen (HLA)-compatible donor after myeloablative conditioning with etoposide and fractionated total body irradiation (12 Gy; posttransplant day [PTD] 0).” (opens the source at this quote in a new tab)
“A specific mutation was not detected, but the deletion of a base in position 1060 suggested potential acyclovir resistance, which was subsequently confirmed by phenotypic culture testing.” (opens the source at this quote in a new tab)
“A treatment request for pritelivir in the context of an expanded access program was submitted to the manufacturer (AiCuris) for the treatment of this episode, but pritelivir eventually arrived at our institution after completion of treatment for this fourth episode. However, a fifth stomatitis episode was diagnosed (confirmed by positive HSV-1 PCR, CT 24) on PTD 444” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection: second of 2 participants

“A 42-year-old patient received an allogeneic HCT from a haploidentical donor for myelodysplastic syndrome.” (opens the source at this quote in a new tab)
“However, molecular testing confirmed the presence of acyclovir-resistant HSV-1 by sequencing of the thymidine kinase gene (R281STOP) on PTD 105.” (opens the source at this quote in a new tab)
“On PTD 146, 9 days after the second dose of cidofovir, the patient developed a third episode of stomatitis associated with multiple ulcerative painful lesions of the hard palate” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection: prior therapy as summarized in a commentary

“the patients developed recurrent HSV-1 oral lesions while on valacyclovir prophylaxis and required multiple courses of intravenous foscarnet and/or cidofovir to control the infection.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with genital HSV-2 infection: first of 2 participants

“The first patient received HSCT for a sickle-cell disease. Three months later, while on sirolimus-based immunosuppressive therapy and valaciclovir prophylaxis, she developed widespread painful genital and anal ulcerations, with positive HSV-2 PCR of a local swab” (opens the source at this quote in a new tab)
“Genotypic resistance testing revealed a L228Stop frameshift mutation in HSV thymidine kinase (TK) (encoded by the UL23 gene), associated with high-level resistance to aciclovir. A 2 week course of foscarnet (40 mg/kg/8 h) provided no clinical benefit and had to be stopped because of severe electrolyte disturbances.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with genital HSV-2 infection: second of 2 participants

“The second patient received HSCT for AML. During the previous 15 years, she received iterative courses of valaciclovir for recurrent HSV genital infections. Six months after HSCT, while on ciclosporin, steroids, vedolizumab and ruxolitinib for graft-versus-host-disease management, and valaciclovir prophylaxis, she developed aciclovir-resistant HSV-2 infection (L263Stop frameshift mutation in the UL23 gene), which was successfully treated with foscavir. Two months later, following a relapse of leukaemia treated with cytarabine and gemtuzumab ozogamicin, she presented with a recurrence of aciclovir-resistant HSV-2 genital infection due to another frameshift mutation in TK (D229Stop).” (opens the source at this quote in a new tab)

Stem cell transplant recipient with HSV-2 infection: characteristics as recorded in a review table

Field	Quoted review table entry
Age and sex	“72/F”
Underlying condition	“MDS with RSAS s/p allogeneic HCT”
Immunosuppression	“Cyclosporin, steroids, ECP”
HSV infection	“HSV-2, genital and buttock”
Resistance diagnosis	“H214HR mutation (ACV-R)”
Treatment	“i.v. ACV (7 w) Topical imiquimod FOS CDV Pritelivir (4 w)”
Adverse effects of treatment	“FOS-induced severe electrolyte disturbances, seizure, ICU admission”

Person living with HIV with orolabial HSV-2 infection: HIV status, prior therapy, and resistance

“A 53-year-old male originally from Haiti was diagnosed with HIV in 2016 with initial viral load of 266,576 copies/mL and a CD4+ count of 3 × 106/L (0.4%) prompting treatment with abacavir, lamivudine, and dolutegravir.” (opens the source at this quote in a new tab)
“From 2018 to 2021, the patient developed numerous local recurrences. Multiple therapeutic regimens were trialed including topical foscarnet 1%, imiquimod 5% cream, topical cidofovir 1% cream, intravenous foscarnet, and intravenous cidofovir as summarized in Figure 1.” (opens the source at this quote in a new tab)
“In late 2021, the patient developed a large lesion on his right upper lip. His CD4+ count was stable at 238 cells/mm3 (12.4%) and his HIV viral load remained suppressed at <40 copies/mL. A swab of the lesion tested positive for HSV-2 by PCR. Subsequent genotypic resistance testing revealed a M183X nonsense mutation in UL23 encoding the viral thymidine kinase which leads to resistance to acyclovir and penciclovir” (opens the source at this quote in a new tab)
“The patient was again treated with IV cidofovir, but with limited improvement. Foscarnet was not prescribed to avoid the need for admission during the COVID-19 pandemic.” (opens the source at this quote in a new tab)

Stem cell transplant recipient with esophagitis: presentation, resistance, and prior therapy

“A 56-year-old haploidentical HSCT recipient, in complete remission from a mantle-cell lymphoma, was hospitalized 60 days post-transplantation due to severe facial mucocutaneous disease and esophagitis requiring the insertion of a percutaneous endoscopic gastrostomy (PEG) tube” (opens the source at this quote in a new tab)
“To detect antiviral resistance, the UL23 (thymidine kinase) and UL30 (DNA polymerase) genes were amplified and sequenced from oesophageal biopsy, oral swabs, and blood-identifying mutations associated with acyclovir (605V in UL30 and 430insG in UL23) and foscarnet resistance (605V in UL30; Fig. S1). Thus, a dose of i.v. cidofovir was administered once weekly for 2 weeks, but without clinical response.” (opens the source at this quote in a new tab)

Herpes simplex encephalitis: participant and course before pritelivir

“The patient was a 49-year-old man who received HCT for treatment-related acute myeloid leukemia after multiple myeloma therapies.” (opens the source at this quote in a new tab)
“On day +178, while still on valacyclovir prophylaxis, the patient presented to the allogeneic HCT outpatient clinic with fever, cognitive impairment, and general weakness.” (opens the source at this quote in a new tab)
“Resistance to acyclovir in the CSF could not be confirmed by UL23 genotyping, which identified polymorphisms C6G, G251C, P268T, Q89R, A192V, V267L, and D286E. We did not test for UL30 mutations in this case.” (opens the source at this quote in a new tab)
“Despite several days of intravenous acyclovir therapy and discontinuation of sedatives, the patient remained unresponsive even to painful stimuli.” (opens the source at this quote in a new tab)
“A subsequent cMRI showed ongoing progress with necrotic areas. As ultima ratio, the use of pritelivir was requested through the EAP.” (opens the source at this quote in a new tab)

Herpes simplex encephalitis: participant as described in the congress poster

“49-year-old male 100 days after HCT for acute myeloid leukemia with good hematological engraftment and without any signs of acute graft-versus-host disease” (opens the source at this quote in a new tab)

Pediatric transplant recipients: age, sex, and virus type in the 8-participant series

“Patients were aged between 1.5 and 17 years old and included 62.5% males (n = 5) and 37.5% females (n = 3).” (opens the source at this quote in a new tab)
“All patients isolated HSV-1 strain.” (opens the source at this quote in a new tab)

Pediatric transplant recipients: characteristics of the 3 participants whose antiviral drugs included pritelivir

Characteristic	Case 1	Case 4	Case 5
Age, years	“1.5”	“15”	“1.5”
Diagnosis	“JMML, secondary graft failure post first HSCT”	“Sickle cell disease with CNS vasculopathy, primary graft failure”	“MDS with SAMD9 and monosomy 7”
Duration of prior acyclovir	“4 months”	“2 months”	“2 months”
Onset of HSV	“D+24”	“D+18”	“D+44”“D+159”
Sites of HSV disease	“mucocutaneous, enterocolitis, pneumonitis, blood viremia”	“Mucocutaneous, blood viremia”	“mucocutaneous lesions, blood viremia, pneumonitis”
Mutation identified	“TK 460-464delC”	“TK novel W88 stop codon”	“TK 430-436insG”“DNA Pol R700G”
Antiviral drugs used	“Acyclovir Foscarnet Pritelivir”	“Acyclovir Foscarnet Pritelivir”	“Acyclovir Foscarnet Pritleivir”

Hematopoietic cell transplant recipient treated in two episodes: infection and prior therapy by episode

Characteristic	First episode	Second episode
HSV infection	“Large ulcer on the tongue and a few small ulcers on the palate, buccal mucosa, and lips. Phenotypic resistance test results were ACV and FOS sensitive.”	“Small ulcers on the lips, buccal mucosa, and palate. Phenotypic resistance test results were ACV and FOS sensitive.”
Standard-of-care treatment	“High-dose VACV High-dose i.v. ACV i.v. FOS Topical imiquimod Topical CDV”	“High-dose VACV High-dose i.v. ACV Because of renal failure, FOS and CDV were not administered.”
Adverse events of standard-of-care treatment	“FOS-induced renal injury and penile lesion.”	“None”

Hematopoietic cell transplant recipient with oral HSV-1 infection: resistance and renal function before pritelivir

“A 37-year-old woman was referred to our hospital with refractory acute myeloid leukemia.” (opens the source at this quote in a new tab)
“We found a mutation in UL30 A605V which is associated with acyclovir and foscarnet resistance. No mutations were found in thymidine kinase.” (opens the source at this quote in a new tab)
“Although her oral ulcerations responded well, her clinical condition worsened (WHO 3, losing weight, nausea) and her kidney function deteriorated within three weeks to 42 mL/min/1.73 m2.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipient with HSV pneumonitis, a use outside the labeled indication: course before pritelivir

“Female 61 years of age, underwent an upfront allo-HCT for chronic myelomonocytic leukemia (CMML) after a FLAMSA-RIC regimen.” (opens the source at this quote in a new tab)
“During foscarnet therapy, her renal function deteriorated from 64 to 32 mL/min/1.73 m2 and doses were adjusted according to the SmpC.” (opens the source at this quote in a new tab)
“BAL was repeated and showed a strongly increased HSV load (>100,000 copies/mL) indicating a clinically refractory and progressive HSV pneumonitis under foscarnet.” (opens the source at this quote in a new tab)
“Analysis for susceptibility to antiviral agents showed mutations in HSV polymerase associated with acyclovir and foscarnet resistance.” (opens the source at this quote in a new tab)

Person living with HIV with anogenital HSV-2 infection: immune status and resistance

“Patient 9, classified as HIV stage C3 with a history of cryptococcal infection at the time of diagnosis, had well-controlled HIV viral load but a persistently low CD4+ T-cell count of 90 cells/mm3.” (opens the source at this quote in a new tab)
“After one month of FOS therapy, a genotypic analysis revealed the emergence of an UL30 mutation (R628C), suggesting potential resistance to both ACV and FOS” (opens the source at this quote in a new tab)

Early access program: healing within 28 and 42 days in the sponsor's aggregate data

Outcome	Proportion	Treatment cycles
Healed or partially healed within 28 days	“63%”	“(86/137)”
Healed or partially healed within 42 days	“87%”	“(119/137)”

“Status as of Apr 26, 2024. 10 out of 147 treatment cycles excluded, since not evaluable (no post-baseline information available). "Unknowns" considered as not healed.” (opens the source at this quote in a new tab)

Early access program: documented healing in an earlier interim analysis

“Interim analysis: 31 out of 44 evaluable patients with documented healing of lesions (70%)” (opens the source at this quote in a new tab)

Early access program: severe manifestations noted in a congress poster

“In addition, the program successfully supported patients with severe manifestations, such as herpes simplex encephalitis” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection: response in 2 participants

“Outpatient treatment with pritelivir was administered, with partial response by week 1 of treatment and complete response by week 4 of treatment in both patients.” (opens the source at this quote in a new tab)
“with complete resolution of all lesions attained by 34 days of therapy” (opens the source at this quote in a new tab)
“The patient had a partial clinical response within 1 week and an almost complete resolution of the oral lesions by 2 weeks after pritelivir initiation” (opens the source at this quote in a new tab)
“After a 30-day course of treatment with pritelivir, the infection resolved completely, and no secondary prophylaxis was initiated, considering that immunosuppression had been tapered off.” (opens the source at this quote in a new tab)
“We documented complete clinical responses in both cases, and clinical responses were evident as fast as 7 days into treatment.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection: recurrence after pritelivir in 1 of 2 participants

“A recurrent episode of HSV-1 stomatitis was detected after stopping pritelivir at PTD 562, which was treated succesfully with cidofovir i.v. for 2 weeks.” (opens the source at this quote in a new tab)
“In the first case, infection relapse was observed within 27 days after stopping treatment with pritelivir, considering the overall immunosuppression of this patient.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with genital HSV-2 infection: healing and relapses in the first of 2 participants

“In the patient, pritelivir resulted in both lesion healing and virological control. Pritelivir was well tolerated and stopped on Day 42 after reaching almost complete resolution of HSV-2 infection. A first relapse occurred 4 weeks after pritelivir discontinuation. Foscarnet was reintroduced, but had to be stopped because of toxicity, without clinical improvement of lesions. Complete resolution of genital lesions was achieved with a 42 day course of pritelivir. The same evolution was observed during the next relapse, which occurred 2 weeks after the discontinuation of the second course of pritelivir. No pritelivir resistance-associated mutation (RAM) was detected during these relapses.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with genital HSV-2 infection: healing and recurrences in the second of 2 participants

“Because of failure of a 3 week course of foscavir, she was treated with pritelivir for 28 days, with good efficacy and tolerance. During the subsequent 7 months, she presented with three successive aciclovir-resistant HSV-2 genital recurrences, while on valaciclovir prophylaxis. Different patterns of aciclovir resistance were evidenced, but no pritelivir RAM was detected. The first two episodes were self-limited and resolved spontaneously, but the third one required a new 28 day course of pritelivir.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with genital HSV-2 infection: authors' account of relapse and resistance

“In the two patients reported here, early relapses might have been favoured by severe immunodeficiency, persistent selection pressure by valaciclovir prophylaxis (both patients) and incomplete healing of the lesions at the end of the first pritelivir course (patient 1).” (opens the source at this quote in a new tab)
“Moreover, no resistance to pritelivir emerged despite prolonged viral shedding and longer cumulative drug exposure than in immunocompetent patients included in the Phase 2 trials” (opens the source at this quote in a new tab)

Stem cell transplant recipient with HSV-2 infection: symptomatic and virologic control

“Compassionate acquisition of the novel oral helicase-primase inhibitor pritelivir provided both symptomatic and virological control for the duration of its use.” (opens the source at this quote in a new tab)

“On pritelivir improvement after 2 w with healing after 4 w.” (opens the source at this quote in a new tab)

Person living with HIV with orolabial HSV-2 infection: lesion response

“Within 1 week the lesion became flatter, drier, and less painful. After 28 days the lesion had reduced in size and the overlying skin appeared less inflamed. Even after the pritelivir course was complete, healing of the lesion continued until eventual resolution indicating the initial treatment duration was adequate.” (opens the source at this quote in a new tab)

Stem cell transplant recipient with esophagitis: response, relapse, and resistance testing

“Oral and oesophageal ulcerations began to improve within the first week, with marked recovery by 1 month” (opens the source at this quote in a new tab)
“HSV load in both blood and vesicular swabs declined to undetectable levels. Four weeks after discontinuing pritelivir, the patient experienced clinical relapse with stomatitis and high viral load (VL) on vesicular swabs (peak 8.7 log copies/mL), whereas blood remained negative. To rule out the development of mutations potentially associated with pritelivir resistance, UL5 and UL52 (helicase/primase complex) were sequenced, but no relevant mutations were found.” (opens the source at this quote in a new tab)
“genetic analysis of the UL5/UL52 complex in our case did not show any specific pattern of resistance associated with pritelivir.” (opens the source at this quote in a new tab)

Stem cell transplant recipient with esophagitis: secondary prophylaxis and reintroduction

“The patient started secondary prophylaxis with pritelivir (100 mg/d following loading dose of 400 mg) for 3 months through expanded access approval, and no recurrences were reported.” (opens the source at this quote in a new tab)
“As the test indicated a lack of HSV-specific T-cell response and the patient experienced recurrent mouth ulcerations after stopping prophylaxis, pritelivir was reintroduced, leading to sustained clinical response.” (opens the source at this quote in a new tab)
“In our case, pritelivir was effective in treating a life-threatening mucocutaneous disease with severe gastrointestinal mucositis that impaired both oral drug intake and potentially gastrointestinal absorption.” (opens the source at this quote in a new tab)

Stem cell transplant recipient with esophagitis: case shown in the sponsor's corporate slides

Item	Quoted slide text
Participant	“56-year-old female”
Underlying condition	“Allogenic HSCT, Refractory NHL”
Presentation	“Severe mucositis and esophagitis”
Oral intake	“Patient was unable to eat and drink”
Resistance	“Resistance to Acyclovir and Foscarnet”
Prior salvage therapy	“Cidofovir salvage therapy was ineffective”
Outcome	“At day 26 of Pritelivir treatment complete healing of esophageal mucosa. Patient started drinking”
Continuation	“Investigator requested continuation of Pritelivir therapy”

Herpes simplex encephalitis, a use outside the labeled indication: clinical, imaging, and virologic course

“Four days after initiation of therapy, we observed a clinical response with a steady increase in the patient’s level of vigilance. Six days after starting pritelivir therapy, the patient was able to answer simple, closed questions and showed prompt motor activity, initially on command and later spontaneously.” (opens the source at this quote in a new tab)
“Eight days after starting pritelivir therapy, the MRI showed no further progression for the first time since the HSE recurrence. The CSF HSV1 viral load fell below the limit of quantification four weeks after the start of pritelivir therapy.” (opens the source at this quote in a new tab)

Herpes simplex encephalitis, a use outside the labeled indication: pritelivir concentrations in plasma and cerebrospinal fluid

“Bioanalytical evaluation revealed pritelivir concentrations of 3634 ng/mL in plasma and 43.5 ng/mL in CSF. The CSF concentration exceeded the pritelivir in vitro 50% effective concentration (EC50) of 10 ng/mL for HSV1 inhibition by approximately 4-fold” (opens the source at this quote in a new tab)

Herpes simplex encephalitis, a use outside the labeled indication: summary in the congress poster

“The addition of pritelivir was followed by a significant reduction in cerebrospinal fluid (CSF) HSV-1 viral load to undetectable levels, clinical improvement and stabilization of neurological symptoms. The drug was well tolerated, with plasma and CSF concentrations above the effective antiviral threshold.” (opens the source at this quote in a new tab)

Pediatric transplant recipients, a use outside the labeled indication: outcomes of the 3 participants whose antiviral drugs included pritelivir

Case	Outcome of HSV infection
Case 1	“Non-responder”“Died secondary to severe HSV-associated ARDS.”
Case 4	“Responder”“Blood viremia (2 days foscarnet)”“Mucocutaneous (10 days foscarnet)”
Case 5, first episode	“First responder”“Blood viremia (7 days foscarnet)”“Mucocutaneous (28 days pritelivir)”“Respiratory viremia (24 days pritelivir)”
Case 5, second episode	“Second non-responder”“Died secondary to refractory HSV, severe ARDS”

“In addition, for the three patients who were treated with third-line antivirals, only one had a good clinical response with resolution of their infection.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipient treated in two episodes: outcome by episode

Episode	Pritelivir administration	Outcome
First episode	“42 days. 400 mg loading dose, 100 mg daily”	“Partial resolution on FOS. Complete resolution on pritelivir.”
Second episode	“42 days. 400 mg loading dose, 100 mg daily”	“No response to VACV and i.v. ACV. Complete resolution on pritelivir.”

“Pritelivir treatment resulted in significant improvement after 1 week, complete resolution, with no apparent adverse effects.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection and HSV pneumonitis: response in 2 participants

“After 1 week of treatment her oral ulcerations resolved, and she completed 4 weeks of treatment without significant toxicities.” (opens the source at this quote in a new tab)
“Her HSV responded well to the treatment. After 4 weeks of treatment, HSV was repeatedly undetectable in BAL.” (opens the source at this quote in a new tab)

Person living with HIV with anogenital HSV-2 infection: partial response

“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)

Hematopoietic cell transplant recipients with oral HSV-1 infection: outpatient treatment and the participants' stated preference

“In fact, for both episodes treated with pritelivir at our institution, patients remained outpatients and very much appreciated the fact that they did not have to be readmitted for another i.v.-administered antiviral treatment.” (opens the source at this quote in a new tab)

Early access program: drug-related adverse events in the sponsor's aggregate data

“Safety: 13 / 94 patients (13.8%)” (opens the source at this quote in a new tab)
“showed drug-related TEAEs” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection: tolerability in 2 participants

“No adverse events were noted.” (opens the source at this quote in a new tab)
“The therapy with pritelivir was well tolerated, and no major adverse events were reported by the patient.” (opens the source at this quote in a new tab)
“The pritelivir was well tolerated, and no adverse events or relapses were noted.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with genital HSV-2 infection: tolerability in 2 participants

“Pritelivir was well tolerated, probably because there is no eukaryotic equivalent to the helicase-primase complex.” (opens the source at this quote in a new tab)

Stem cell transplant recipient with esophagitis: tolerability of prolonged courses

“pritelivir was administered via PEG with excellent compliance and no adverse events” (opens the source at this quote in a new tab)
“Consistently, our patient received prolonged courses with pritelivir, and no toxicity occurred.” (opens the source at this quote in a new tab)

Stem cell transplant recipient with esophagitis: authors' note on earlier long-term safety questions

“Long-term safety of pritelivir was initially questioned due to haematology and skin-related findings in a chronic toxicity study in monkeys, which led to a clinical hold and the early termination of a parallel trial comparing pritelivir with valacyclovir for 28 days in patients with genital herpes” (opens the source at this quote in a new tab)
“However, the hold was subsequently lifted based on an additional chronic toxicity study, and the overall favourable clinical data” (opens the source at this quote in a new tab)

Herpes simplex encephalitis, a use outside the labeled indication: tolerability with intravenous acyclovir

“No relevant adverse effects of acyclovir/pritelivir treatment were observed.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipient treated in two episodes: tolerability

“On D+104, compassionate treatment with pritelivir was initiated for a 42-day course (400 mg loading dose and 100 mg daily afterwards), resulting in a complete response with no apparent side effects identified.” (opens the source at this quote in a new tab)
“Pritelivir treatment resulted in significant improvement after 1 week, complete resolution, with no apparent adverse effects.” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection and HSV pneumonitis: tolerability and one death during treatment

“After 1 week of treatment her oral ulcerations resolved, and she completed 4 weeks of treatment without significant toxicities.” (opens the source at this quote in a new tab)
“Unfortunately, the patient developed an idiopathic lung syndrome and multiorgan failure and died while on pritelivir treatment.” (opens the source at this quote in a new tab)

Pediatric transplant recipients, a use outside the labeled indication: deaths among participants whose antiviral drugs included pritelivir

“Died secondary to severe HSV-associated ARDS.” (opens the source at this quote in a new tab)
“Died secondary to refractory HSV, severe ARDS” (opens the source at this quote in a new tab)

Pediatric use: absence of safety data

“This is even more challenging for pediatric patients, for whom there is no safety data or licensing.” (opens the source at this quote in a new tab)

Summary

The expanded access record (NCT05844436) lists a status of Available and no location data. Aggregate early access outcomes come from sponsor slides alone: at the April 2024 data cut-off, 86 of 137 evaluable treatment cycles (63%) were healed or partially healed within 28 days, a category that combines complete and partial healing. Published reports are uncontrolled case reports and series with 1 to 3 pritelivir recipients each. Relapse after pritelivir was stopped is described in 3 reports. Use for encephalitis, pneumonitis, secondary prophylaxis, and children rests on 1 to 3 participants per use, and the encephalitis participant also received intravenous acyclovir. In the pediatric series, 1 of 3 pritelivir recipients had a good clinical response.

Sponsor aggregate data: excluded treatment cycles and preliminary status

“10 out of 147 treatment cycles excluded, since not evaluable (no post-baseline information available). "Unknowns" considered as not healed.” (opens the source at this quote in a new tab)

“All data included in this presentation are preliminary unless explicitly stated otherwise” (opens the source at this quote in a new tab)

Hematopoietic cell transplant recipients with oral HSV-1 infection: authors' statements on the evidence and on secondary prophylaxis

“However, there is a paucity of clinical data on pritelivir administration in real life.” (opens the source at this quote in a new tab)
“Although promising, more data from phase 3 clinical trials are required to better describe the efficacy and safety parameters of this agent and its position in clinical practice.” (opens the source at this quote in a new tab)
“Data on secondary prophylaxis in acyclovir-r/r HSV infections are lacking, and there is no consensus on what to administer and for how long to prevent further relapses. Further studies to address this matter are required. Whether pritelivir may also be used as secondary prophylaxis in patients with multiple recurrences and persistent immunosuppression, at what dose, and for how long remain, at the time, unanswered questions” (opens the source at this quote in a new tab)

Commentary: open questions on severe disease and long-term prophylaxis

“However, many questions remain, including whether pritelivir or amenamevir can be used to treat severe HSV disease such as disseminated infection, end-organ disease, and meningoencephalitis, or if these agents have a role in long-term prophylaxis against HSV.” (opens the source at this quote in a new tab)

Herpes simplex encephalitis: contribution of concurrent acyclovir and need for further data

“this suggests that the combination may have contributed to the observed clinical improvement, especially since no confirmed acyclovir resistance was detected.” (opens the source at this quote in a new tab)
“Further clinical data are needed to elucidate its therapeutic benefits and to determine whether earlier intervention could prevent long-term neurological sequelae.” (opens the source at this quote in a new tab)

Herpes simplex encephalitis: sponsor employment of authors

“They are employees of AiCuris Anti-Infective Cures AG, the company that develops pritelivir and provided the drug in an Early Access Program.” (opens the source at this quote in a new tab)

Pediatric transplant recipients: small numbers and access to treatment

“While significance cannot be determined due to low patient numbers and insufficient statistical power, several potential risk factors for acyclovir-resistant HSV emerged from reviewing the cases in our center.” (opens the source at this quote in a new tab)
“Access to HPIs rely upon compassionate access or enrolment on a clinical trial, meaning the practicality of accessing these treatments in a timely manner is not always feasible. This is even more challenging for pediatric patients, for whom there is no safety data or licensing.” (opens the source at this quote in a new tab)

Review assessment of the early access evidence in transplant recipients

“Limited data from the Early Access Program, which allows compassionate use, suggest that pritelivir holds promise as a treatment option for HCT recipients with R/R HSV infections.” (opens the source at this quote in a new tab)

Review assessment of the characterization of toxicity

“It is claimed that amenamevir and pritelivir are well-tolerated but the toxicity profile is not yet thoroughly investigated and is used for a relatively short treatment period (maximum of 42 days)” (opens the source at this quote in a new tab)

Case report on resistance monitoring during pritelivir treatment: removal by the publisher at the authors' request

“This article has been removed at the request of Authors.” (opens the source at this quote in a new tab)
“The authors have requested the removal of this manuscript due to legal obligations involving Aicuris, HCL (France), and HUG (Switzerland). These obligations currently prevent the independent publication of the work, as it is part of an ongoing multicenter study whose results are scheduled for release in 2026.” (opens the source at this quote in a new tab)