The U.K. National Institute for Health and Care Excellence recommended the use of Merck & Co. Inc.'s Prevymis to help prevent a virus infection in certain post-stem cell transplant patients.

In a final appraisal document, Prevymis, or letermovir, was recommended as an option to help prevent cytomegalovirus reactivation and disease after an allogeneic hematopoietic stem cell transplant in adults whose blood tests show the presence of the virus. Allogeneic hematopoietic stem cell transplant involves a patient receiving blood-forming stem cells from a donor.

Cytomegalovirus, or CMV, is a common virus that lies dormant in the body and spreads through bodily fluids.

Current treatments for CMV infection include ganciclovir, marketed by Roche Holding AG as Cytovene and Cymevene; valganciclovir, another Roche drug sold as Valcyte; and foscarnet, a preemptive therapy. However, NICE said these medicines are linked to severe side effects.

There is no licensed treatment available to specifically prevent CMV reactivation after a stem cell transplant.

The U.K. pricing authority's recommendation was based on clinical trial evidence showing Prevymis' effectiveness in lessening CMV infection as well as reducing the need for preemptive therapy.

Additionally, the drug's most reasonable cost-effectiveness estimates were within the range that NICE usually considers acceptable.

The oral formulation of Prevymis has a list price of £3,723.16 for 28 tablets in 240-milligram doses. Through a commercial agreement with Kenilworth, N.J.-based Merck, the drug will be available to the National Health Service at a confidential discount.