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Prevymis

Generic Name: letermovir (oral/injection) (le TERM oh vir)
Brand Names: Prevymis

Medically reviewed on Feb 26, 2018

What is Prevymis?

Prevymis (letermovir) is an antiviral medicine used to help prevent cytomegalovirus (CMV) infection after a stem cell (bone marrow) transplant from a donor.

Prevymis is for use in adults who are seropositive for CMV. Seropositive means that the virus is in your blood even if you do not show any symptoms of infection.

A CMV-seropositive person is at risk for "reactivation" of the virus if the immune system becomes weak. While normally treatable, CMV infection can be serious in people undergoing a stem cell transplant.

Prevymis comes as a tablet or can be given by your doctor through an IV line (intravenously).

Important Information

Tell your doctor about all your current medicines and any you start or stop using. Many drugs can interact with letermovir, and some drugs should not be used together.

Before taking this medicine

Some medicines can cause unwanted or dangerous effects when used with Prevymis. Your doctor may need to change your treatment plan if you use any of the following drugs:

To make sure Prevymis is safe for you, tell your doctor if you have ever had:

It is not known whether Prevymis will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It is not known whether letermovir passes into breast milk or if it could affect the nursing baby. Tell your doctor if you are breast-feeding.

How should I use Prevymis?

Use Prevymis exactly as prescribed by your doctor. Follow all directions on your prescription label. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Prevymis oral is a tablet taken by mouth. The injection is given through an IV into a vein.

You may take the tablets with or without food.

Do not crush, chew, or break a Prevymis tablet. Swallow the tablet whole.

You may be shown how to use Prevymis injections at home. Do not give yourself this medicine if you do not understand how to use the injection and properly dispose of needles, IV tubing, and other items used.

You may need to mix the injection solution with a liquid (diluent) in an IV bag before using it. If you are using the injections at home, be sure you understand how to properly mix and store the medicine.

You can store the mixture for up to 24 hours at room temperature, or up to 48 hours in a refrigerator.

Prevymis injection must be given slowly, and the infusion can take at least 1 hour to use all of the medicine in the IV bag.

Prevymis tablets or injections are usually given once per day for up to 100 days after your stem cell transplant.

Use this medicine for the full prescribed length of time, even if you have no symptoms. Skipping doses may increase your risk of further infection that is resistant to medication.

Store tablets or unmixed injection solution in the original packaging at room temperature, away from moisture, heat, and light. Keep each tablet in the foil blister pack until you are ready to take a tablet.

Do not shake the injection solution bottle. Prepare your dose only when you are ready to give an injection. Do not use if the medicine has changed colors or has particles in it. Call your pharmacist for new medicine.

Each single-use vial (bottle) of Prevymis injection is for one use only. Throw it away after one use, even if there is still medicine left inside.

Prevymis dosing information

Usual Adult Dose for CMV Prophylaxis:

Initiate therapy between Day 0 and Day 28 post-transplantation (before or after engraftment):

Initial dose: 480 mg orally or by IV infusion once a day

Co-administration with Cyclosporine: 240 mg orally or IV infusion once a day

Duration of therapy: Through Day 100 post-transplantation

Comments:
-Oral and IV doses may be used interchangeably; patients should be switched to oral therapy as soon as possible due to the presence of hydroxypropyl betadex in the IV formulation.
-During clinical trials, the median time to engraftment (defined as absolute neutrophil count of 500/mm3 or greater on 3 consecutive days after transplantation) was 19 days in letermovir-treated patients.
-Potentially significant drug interactions resulting in adverse reactions or reduced therapeutic effect of this drug or the concomitant drug are possible, therefore, consider drug interactions when initiating or completing therapy.

Use: For the prophylaxis of cytomegalovirus (CMV) infection and disease in CMV-seropositive recipients of an allogeneic hematopoietic stem cell transplant (HSCT).

See also: Dosage Information (in more detail)

What happens if I miss a dose?

Use the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using Prevymis?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Prevymis side effects

Get emergency medical help if you have signs of an allergic reaction to Prevymis: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • fast or irregular heartbeats.

Serious side effects may occur if you also use certain other medications.

Common Prevymis side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Prevymis?

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

Tell your doctor about all your current medicines and any you start or stop using. If you also use cyclosporine, your Prevymis dose will need to be adjusted.

Other drugs may interact with letermovir, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Prevymis only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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