What are the adverse reactions of Letermovir?

Letermovir as an antiviral drug targetingCMV DNA terminator complex, has shown significant efficacy in preventing cytomegalovirus (CMV) infection in allogeneic hematopoietic stem cell transplantation (HSCT) and high-risk kidney transplant recipients. However, its clinical application requires vigilance against potential adverse reactions. According to clinical trials, the drug may cause mild multi-system symptoms, including gastrointestinal reactions such as nausea, vomiting, diarrhea and abdominal pain, central nervous system-related headaches and fatigue, and respiratory symptoms such as cough and local edema. It is worth noting that the incidence of these adverse reactions is similar to that of the placebo group, and most of them are mild to moderate and self-limiting. They usually do not require special treatment, and the symptoms can resolve spontaneously after continued medication or adjustment of the dosage regimen.

In terms of special risks, the intravenous formulation of letermovir contains hydroxypropyl betaide as an excipient, which may cause metabolic burden after long-term infusion. Particular attention needs to be paid to serum creatinine monitoring in patients with renal insufficiency. Drug interaction studies have shown that dosage adjustments are required when used in combination with immunosuppressants such as cyclosporine to avoid changes in pharmacodynamics. In addition, electron microscopy observation revealed abnormal virion maturation, suggesting that long-term medication needs to monitor the development of drug-resistant strains, although the current clinical drug resistance rate is still less than 1%. For pediatric patients, the administration method of mixing granules with soft food may increase the risk of aspiration, and the operating instructions must be strictly adhered to within 10 minutes.

In clinical practice, physicians should comprehensively evaluate patients' underlying diseases, immune status and concomitant medications, and formulate individualized monitoring plans. For HSCT recipients, it is recommended to continue to track CMV load until 100 days after drug withdrawal; kidney transplant patients need to pay attention to signs of viral activation within 200 days after transplantation. It is necessary to emphasize the importance of swallowing tablets whole and avoid breaking or chewing the drug, which may cause fluctuations in blood concentration. If persistent vomiting or severe diarrhea occurs, electrolyte balance should be assessed promptly and supportive treatment should be considered to ensure maximum safety and efficacy of medication.

Reference materials:https://en.wikipedia.org/wiki/Letermovir