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NICE recommend letermovir (Prevymis) for treating cytomegalovirus after stem cell transplant

Prevymis▼, for Stem cell transplant and Cytomegalovirus infection from Merck Sharp and Dohme

The National Institute for Health and Care Excellence (NICE) have recommended that Merck Sharp and Dohme's treatment for cytomegalovirus, letermovir, brand name Prevymis, for use by the NHS in England.

Letermovir is recommended, within its marketing authorisation, as an option for preventing cytomegalovirus (CMV) reactivation and disease after an allogeneic haematopoietic stem cell transplant (HSCT) in adults who are seropositive for CMV.

CMV is similar to the herpes virus that causes cold sores and chickenpox.

Once you have the virus, it stays in your body for the rest of your life.

Your immune system usually controls the virus and most people don't realise they have it. In patients undergoing stem cell transplant their immune system is compromised and so they are more prone to contracting CMV.

You can follow developments on Prevymis by using our Medicines Tracker service which provides users with updates about the medicines they are interested in.

Why the European Medicines Agency made these recommendations
Current management of CMV after an allogeneic HSCT (a stem cell transplant from a donor) involves regular blood tests to monitor CMV levels (with or without aciclovir). If CMV levels rise, treatment with ganciclovir, valganciclovir or foscarnet (pre-emptive therapy) is started to prevent disease but this can cause severe side effects. Letermovir is an
option for reducing CMV and is safer than pre-emptive therapy.

Clinical trial evidence shows that letermovir is effective in reducing CMV infection and also reduces the need for pre-emptive therapy. The most plausible cost-effectiveness estimates for letermovir are within the range that NICE usually considers acceptable. Therefore, it is recommended.

About Prevymis (source EMA)
Prevymis is an antiviral medicine used to prevent illness caused by cytomegalovirus (CMV) in adults having an allogeneic haematopoietic stem cell transplant to replace their bone marrow. Allogeneic haematopoietic stem cell transplantation involves using stem cells from a donor to replace the recipient’s bone marrow cells to form new bone marrow that produces healthy blood cells.

Many people have CMV in their body but it is usually inactive and it does not cause harm. However, CMV can become active in patients whose immune system is weakened such as those having stem cell transplants.

Because the number of patients with CMV disease is low, the disease is considered ‘rare’, and Prevymis was designated an ‘orphan medicine’ (a medicine used in rare diseases) on 15 April 2011.

For CMV to multiply, its genetic material (DNA) needs to be copied and packaged into protein shells to produce more viruses that can then infect other cells. Letermovir, the active substance in Prevymis, blocks a virus enzyme called ‘terminase’. Terminase is involved in packaging the DNA in the protein shells of the virus. By blocking the enzyme, the medicine prevents viruses from developing properly, so that CMV cannot multiply and infect other cells. This is expected to prevent CMV disease in transplant recipients who already have CMV in their body.

Prevymis was first made available in the EU in 2018. It is manufactured by Merck Sharp & Dohme.

European Medicines Agency website page for Prevymis
NHS website for cytomegalovirus
Contains public sector information licensed under the Open Government Licence v3.0.
Accessed 01/06/19
Links available in full article

© NICE [2019] Letermovir prophylaxis for cytomegalovirus disease after allogeneic stem cell transplant [ID1153] Available from: See Link below. All rights reserved. Subject to Notice of rights
NICE guidance is prepared for the National Health Service in England. All NICE guidance is subject to regular review and may be updated or withdrawn. NICE accepts no responsibility for the use of its content in this product/publication.

The information provided by NICE was accurate at the time this article was issued.

NICE guidelines: Letermovir prophylaxis for cytomegalovirus disease after allogeneic stem cell transplant [ID1153]

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