Budget Impact of Prophylactic Letermovir to Prevent Cytomegalovirus Disease in High-Risk Adult Kidney Transplant Recipients

BACKGROUND/OBJECTIVE: Cytomegalovirus (CMV) causes serious health problems in people with weakened immune systems, particularly those undergoing kidney transplantation. CMV can severely impact transplant outcomes through increased complications, graft loss, morbidity, and mortality. Valganciclovir (VGCV) is a commonly used prophylaxis after kidney transplantation for high-risk patients, but is known to induce leukopenia/neutropenia (LN). In the MK-8228-002 phase III trial, letermovir prophylaxis was non-inferior to VGCV for CMV prevention among high-risk adult kidney transplant recipients, but was also associated with significantly lower LN. This study aimed to evaluate the budget impact of introducing letermovir as a CMV prophylaxis drug for kidney transplant patients, with an increasing market share over 5 years compared with a market scenario with VGCV only, from a United States (US) payer perspective. METHODS: A budget impact analysis was conducted from a US payer perspective, modeling a hypothetical health plan of 1,000,000 members, including 18 high-risk kidney transplant patients per year. The model compared a market scenario with VGCV only (without letermovir) versus a scenario in which letermovir is introduced into a healthcare plan with an increasing market share over 5 years. The model incorporated direct medical costs associated with prophylaxis drug acquisition and administration, LN events, and the downstream effects of LN events (e.g., CMV DNAemia, opportunistic infections, graft rejection/loss). Modeled outcomes included total budget impact and incremental cost per member per month (PMPM, 2025 USD). One-way sensitivity analysis (OWSA) was also conducted. RESULTS: The annual total costs without letermovir were US$1,628,307 for each year and ranged from US$1,604,558 (year 1) to US$1,596,297 (year 5) in the scenario with letermovir. Incremental PMPM ranged from - US$0.0020 in year 1 to - US$0.0027 in year 5, indicating cost savings associated with letermovir in each year. The deterministic sensitivity analysis identified the rate of having LN events on VGCV as the most influential driver of the budget impact results, followed by the annual management cost of LN events and LN-associated events. CONCLUSION: This analysis provides evidence on the potential impact of introducing letermovir into the US market. While the acquisition cost of letermovir is higher than that of VGCV, there are estimated cost savings, primarily driven by the prevention of LN events and their associated downstream clinical consequences, suggesting that the savings from LN avoidance outweigh the incremental prophylaxis costs of introducing letermovir. However, the overall budget impact remains minimal and should be interpreted in the context of the evolving evidence base.