Letermovir Injection

WHY is this medicine prescribed?

Letermovir injection is used to help prevent cytomegalovirus (CMV) infection and disease in certain people who have received a hematopoietic stem-cell transplant (HSCT; a procedure that replaces diseased bone marrow with healthy bone marrow) and are at increased risk of developing a CMV infection. Letermovir is in a class of medications called antivirals. It works by slowing the growth of CMV.

HOW should this medicine be used?

Letermovir injection comes as a liquid to be diluted and given intravenously (into a vein). It is usually injected slowly over a period of 1 hour. It is usually given once a day for as long as you are unable to take letermovir tablets by mouth.

You may receive letermovir injection in a hospital, or you may administer the medication at home. If you will be receiving letermovir injection at home, your healthcare provider will show you how to use the medication. Be sure that you understand these directions, and ask your healthcare provider if you have any questions.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

Are there OTHER USES for this medicine?

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What SPECIAL PRECAUTIONS should I follow?

Before using letermovir injection,

• tell your doctor and pharmacist if you are allergic to letermovir, any other medications, or any of the ingredients in letermovir injection. Ask your pharmacist for a list of the ingredients.
• tell your doctor if you are taking ergot alkaloids such as ergotamine (Ergomar, in Cafergot, Migergot) and dihydroergotamine (D.H.E. 45, Migranal), and pimozide (Orap). Your doctor will probably tell you not to take these medications if you are using letermovir injection.Also tell your doctor if you are taking cyclosporine along with either simvastatin or pitavastatin. Your doctor will probably tell you not to take these combinations of medications with letermovir.
• some medications should not be taken with letermovir injection. Other medications may cause dosing changes or extra monitoring when taken with letermovir injection. Make sure you have discussed any medications you are currently taking or plan to take before starting letermovir injection with your doctor and pharmacist. Before starting, stopping, or changing any medications while receiving letermovir injection, please get the advice of your doctor or pharmacist.
• the following nonprescription or herbal products may interact with letermovir injection: St. John's wort; omeprazole (Prilosec). Be sure to let your doctor and pharmacist know that you are taking these medications before you start receiving letermovir injection. Do not start any of these medications while receiving letermovir injection without discussing with your healthcare provider.
• tell your doctor if you have or have ever had kidney or liver disease.
• tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while using letermovir injection, call your doctor.
• if you are having surgery, including dental surgery, tell the doctor or dentist that you are using letermovir injection.

What SPECIAL DIETARY instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What SIDE EFFECTS can this medicine cause?

Letermovir injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• nausea
• vomiting
• diarrhea
• abdominal pain
• swelling of your arms or legs
• headache
• extreme tiredness

Some side effects can be serious. If you experience any of these symptoms call your doctor immediately:

• fast or irregular heartbeat; feeling weak or dizzy, shortness of breath, chest pain

Letermovir injection may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What OTHER INFORMATION should I know?

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response to letermovir.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.

The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.

AHFS^® Patient Medication Information™. © Copyright, 2024. The American Society of Health-System Pharmacists^®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: February 15, 2018.