letermovir at a glance
Medicine class
Direct-acting antiviral and CMV terminase inhibitor
Usual role
Prevention of CMV reactivation or disease in specified transplant recipients
Available routes
Film-coated tablets or an intravenous infusion given by healthcare professionals
Food
Tablets may be taken with or without food
Specialist oversight
Initiation and interaction management require an experienced transplant clinician
What is letermovir used for?
Licensed uses include CMV prophylaxis in defined transplant settings and within product-specific age and body-weight limits.
Prevention of CMV reactivation and disease in CMV-seropositive recipients of an allogeneic haematopoietic stem-cell transplant.
Prevention of CMV disease in CMV-seronegative kidney recipients whose donor was CMV-seropositive.
How does letermovir work?
Letermovir blocks the CMV DNA terminase complex, preventing copied viral DNA from being correctly cut and packaged into new virus particles.
letermovir preparations and strengths
Solution for infusion
Route: Intravenous
Strengths: 240 mg
Tablet
Route: Oral
Strengths: 240 mg
How to take letermovir
Follow the transplant team's instructions and do not change formulation without specialist advice.
Swallow tablets whole with water; do not divide, crush or chew them.
Tablets may be taken with or without food.
The infusion must be diluted and given through the specified polyethersulfone in-line filter by a healthcare professional.
Tell the transplant team before starting, stopping or changing any prescription, non-prescription or herbal product.
letermovir side effects
Common or expected effects
- Nausea
- Diarrhoea
- Vomiting
Get urgent medical advice
- Hypersensitivity, including a rapidly developing severe allergic reaction
- Possible statin-related muscle injury causing unexplained muscle pain or weakness, especially with fever or malaise
letermovir in pregnancy
Human pregnancy data are unavailable, and animal studies found reproductive toxicity. Letermovir is not recommended during pregnancy or for someone who could become pregnant and is not using contraception. Seek specialist review if pregnancy occurs or is planned.
letermovir while breastfeeding
It is unknown whether letermovir passes into human milk, and risk to a breastfed child cannot be excluded. The patient and prescriber should weigh the benefits of breastfeeding and treatment when deciding whether to stop breastfeeding or avoid letermovir.
letermovir interactions
Letermovir affects several enzymes and transport proteins. A complete review of medicines and herbal products is essential.
Ciclosporin
Increases letermovir exposure and alters several other interactions, requiring specialist review and ciclosporin-level monitoring.
Tacrolimus or sirolimus
Letermovir can increase concentrations. Monitor blood levels and toxicity when letermovir or its route is changed.
St John’s wort
Can lower letermovir exposure and is contraindicated.
Pimozide or ergot alkaloids
Contraindicated because letermovir may increase the risk of serious toxicity.
Common questions about letermovir
Answers are fully visible for fast scanning and source review.
Does letermovir treat active CMV disease?
No. These products are licensed for prevention, not treatment of established CMV disease. Breakthrough CMV requires prompt specialist assessment.
Can the tablets be crushed or chewed?
No. Swallow them whole because dividing, crushing and chewing have not been studied.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.