Prevymis showed less leukopenia and neutropenia compared to valganciclovir during the trial.
Prevymis (letermovir) was more effective in preventing CMV in adult kidney transplant patients than the standard treatment, valganciclovir, in a Phase 3 trial, according to results of a study presented at IDWeek 2022.
Investigators from Merck conducted a phase 3, randomized, double-blind non-inferiority trial in order to compare Prevymis to valganciclovir and their abilities to prevent CMV disease among 601 high-risk adult kidney transplant recipients. The patients were randomized to either receive 480 mg of Prevymis once per day or 900 mg of valganciclovir once per day for 7 days post-transplant for 28 weeks with follow-up through 52 weeks, the study authors explained. The median age for the patients was 52 years in the Prevymis group and 51 years in the valganciclovir group, they added.
Prevymis was approved by the FDA in 2017 for the prophylaxis of CMV infection among adult CMV-seropositive recipients of an allogenic hematopoietic stem cell transplant (HSCT), according to a Merck press release. Valganciclovir is the current standard treatment, the statement continued, though leukopenia (the decrease in white blood cells) and neutropenia (the decrease of the most common white blood cell) can be common hindrances.
The statement also added that CMV can infect anyone of any age, but transplanted organs can carry the disease and infect the recipient. This can lead to end-organ damage and transplant recipients with CMV are at risk for transplant failure and death, the statement said.
At 52 weeks post-transplant, 10.4 percent of the Prevymis group had CMV disease, compared to 11.8 percent of the valganciclovir group, the study authors reported. They said this finding was consistent across all subgroups such as age, gender, race, and geography.
The study authors also observed that after 52 weeks post-transplant, none of the Prevymis participants had adjudicated CMV disease compared to 5 patients (1.7 percent) of the valganciclovir group.
Leukopenia and neutropenia were found to be lower among patients randomized to receive Prevymis compared to valganciclovir, the study authors learned, with leukopenia and neutropenia being 38 percent lower in the Prevymis group compared to valganciclovir.
“There is a need for additional CMV prophylactic options for kidney transplant recipients to help patients reduce risk of opportunistic infections,” Nicholas Kartsonis, MD, senior vice president, vaccines and infectious diseases, Global Clinical Development, Merck Research Laboratories, said in the statement. “These new study results in adult kidney transplant patients are encouraging and demonstrate the potential of PREVYMIS to prevent CMV disease with a therapy that showed lower rates of neutropenia and leukopenia versus the comparator.”
Among the Prevymis group, there were drug-related adverse events reported about 20 percent of patients through week 28 post-transplant, and serious adverse events reported in 1.4 percent of patients, the study authors wrote. In the valganciclovir group, these numbers were higher with 35 percent of patients reporting adverse events and 5.1 percent reporting serious adverse events.
“I was excited to see these trial results that showed that the efficacy of PREVYMIS for prevention of CMV disease in kidney transplant patients was similar to the current standard of care treatment, but with significantly less toxicity,” added Ajit P. Limaye, MD, director, Solid Organ Transplant Infectious Disease Program at University of Washington School of Medicine.