Once-Daily Foscarnet Is Effective for Human Herpesvirus 6 Reactivation after Hematopoietic Stem Cell Transplantation
Issued Date
2023-01-01
Resource Type
ISSN
26666367
Scopus ID
2-s2.0-85151407526
Pubmed ID
36878429
Journal Title
Transplantation and Cellular Therapy
Rights Holder(s)
SCOPUS
Bibliographic Citation
Transplantation and Cellular Therapy (2023)
Suggested Citation
Vittayawacharin P., E'Leimat G., Lee B.J., Griffin S., Doh J., Nam H., Blodget E., Jeyakumar D., Kongtim P., Ciurea S.O. Once-Daily Foscarnet Is Effective for Human Herpesvirus 6 Reactivation after Hematopoietic Stem Cell Transplantation. Transplantation and Cellular Therapy (2023). doi:10.1016/j.jtct.2023.02.022 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/82318
Title
Once-Daily Foscarnet Is Effective for Human Herpesvirus 6 Reactivation after Hematopoietic Stem Cell Transplantation
Author's Affiliation
Other Contributor(s)
Abstract
Human herpesvirus 6 (HHV-6) reactivation is common after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and is associated with higher mortality and increased transplantation-related complications. We hypothesized that preemptive treatment with a short course of foscarnet at a lower cutpoint of plasma HHV-6 viral load would be effective in treating early HHV-6 reactivation, preventing complications and precluding hospitalization of these patients. We reviewed outcomes of adult patients (age ≥18 years) who received preemptive treatment with once-daily foscarnet 60 to 90 mg/kg for 7 days for HHV-6 reactivation after allo-HSCT at our institution between May 2020 and November 2022. Plasma HHV-6 viral load was monitored by quantitative PCR twice monthly in the first 100 days post-transplantation and twice weekly after reactivation until resolution. Eleven patients with a median age of 46 years (range, 23 to 73 years) were included in the analysis. HSCT was performed with a haploidentical donor in 10 patients and with an HLA-matched related donor in 1 patient. The most common diagnosis was acute leukemia (9 patients). Myeloablative and reduced-intensity conditioning regimens were used in 4 and 7 patients, respectively. Ten of the 11 patients received post-transplantation cyclophosphamide-based graft-versus-host disease prophylaxis. The median follow-up was 440 days (range, 174 to 831 days), and the median time to HHV-6 reactivation was 22 days post-transplantation (range, 15 to 89 days). The median viral load at first reactivation was 3,100 copies/mL (range, 210 to 118,000 copies/mL), and the median peak viral load was 11,300 copies/mL (range, 600 to 983,000 copies/mL). All patients received a short course of foscarnet at either 90 mg/kg/day (n = 7) or 60 mg/kg/day (n = 4). In all patients, plasma HHV-6 DNA was undetectable at completion of 1 week of treatment. No HHV-6 encephalitis or pneumonitis occurred. All patients achieved neutrophil and platelet engraftment after a median of 16 days (range, 8 to 22 days) and 26 days (range, 14 to 168 days), respectively, with no secondary graft failure. No complications related to foscarnet administration were noted. One patient with very high HHV-6 viremia had recurrent reactivation and received a second course of foscarnet as an outpatient. A short course of once-daily foscarnet is effective in treating early HHV-6 reactivation post-transplantation and may reduce the incidence of HHV-6-related and treatment-related complications and preclude hospitalization in these patients.