COMBINED FOSCARNET-GANCICLOVIR TREATMENT FOR CYTOMEGALOVIRUS INFECTIONS AFTER ALLOGENEIC HEMOPOIETIC STEM CELL TRANSPLANTATION1

Abstract

In a previous study, we showed that patients undergoing allogeneic hemopoietic stem cell transplantation (HSCT) who had cytomegalovirus (CMV) antigenemia with more than 4 CMV antigen-positive cells/200,000 have a high transplant-related mortality (TRM) rate, despite treatment with ganciclovir or foscarnet. In an attempt to reduce TRM, 32 allogeneic HSCT recipients, between the ages of 16 and 55 years (median, 35 years), with CMV antigenemia (≥5 positive cells) developing at a median interval from HSCT of 49 days, were given combination treatment with foscarnet and ganciclovir for 15 days. The prescribed dose was 180 mg/kg/day of foscarnet and 10 mg/kg/day of ganciclovir: the median administered dose in the first 15 days, after adjusting for creatinine levels and peripheral blood counts, was 64% for foscarnet and 53% for ganciclovir. Maintenance was given with foscarnet and ganciclovir on alternate days for an additional 2 weeks. Thirty-one of 32 patients were on cyclosporine, 30 were on systemic antibiotics, and 9 were on intravenous amphotericin. Median laboratory values on days 1 and 15 of treatment were 1.0 and 1.1 mg/100 ml creatinine, 5.7×109/L and 4.1×109/L white blood cells, and 78×109/L and 72×109/L platelets. All patients cleared CMV antigenemia by day + 15, although CMV antigenemia recurred in 5 patients on maintenance therapy and in 14 patients off maintenance therapy: the dose of foscarnet (but not ganciclovir) received in the first 15 days was significantly lower in patients in whom antigenemia recurred within 30 days (P=0.0002). Six patients died, one with interstitial pneumonia, one with multiorgan failure, and four with infections. Twenty-six patients survived 119-1051 days after transplant. The actuarial TRM rate at 1 year is 23%. Eighteen patients who had received unmanipulated bone marrow transplants from HLA-identical siblings were compared with 15 matched controls who had been treated with a single drug (either foscarnet or ganciclovir) for CMV antigenemia (≤5 cells): the acturial 1 year TRM rate was 13% for patients receiving combined treatment, compared with 47% for controls receiving a single drug (P=0.02). This study shows that combined foscarnet-ganciclovir is one therapeutic option for allogeneic HSCT recipients who develop CMV antigenemia with a high number of CMV antigen-positive cells. Treatment can be given together with cyclosporine and antibiotics with appropriate dose reductions. It produces prompt clearing of CMV infection, and may reduce TRM rates in comparison to single-agent therapy.