Generic name:
Marstacimab - injection
Pronunciation
(mar-STAK-i-mab)
Brand name(s)
Hympavzi
Generic name:
Marstacimab - injection
Pronunciation
(mar-STAK-i-mab)
Brand name(s)
Hympavzi
This medication is used by people with a certain inherited bleeding problem (hemophilia A or B) to help prevent or lessen how often you have bleeding problems. Marstacimab belongs to a class of medications known as monoclonal antibodies. It works by helping your blood to clot normally, which helps prevent bleeding due to hemophilia.
Read the Patient Information Leaflet and Instructions for Use if available from your pharmacist before you start using this medication and each time you get a refill. Ask your health care professional how to prepare and use this medication. If you have any questions, ask your doctor or pharmacist.
Inject this medication under the skin as directed by your doctor, usually once a week. The injection is given in the thighs, or abdomen (at least 2 inches from your belly button). It may also be given by a health care professional in the upper arm (prefilled syringe only), or buttocks (prefilled pen only). The dosage is based on your medical condition, weight, and response to treatment.
You may also require Factor VIII or Factor IX products to treat breakthrough bleeds while using marstacimab. Ask your healthcare professional for more information about the use of these other products and what to do if you have breakthrough bleeding.
Take the medication out of the refrigerator 15 to 30 minutes before you inject it to allow it to reach room temperature. Do not warm up this medication any other way (for example, do not heat it in the microwave, place it in hot water, or leave it in direct sunlight). Do not shake the medication. Before using, check this product for cloudiness, particles, or discoloration. If you see any of these things, do not use the liquid. Before injecting each dose, clean the skin you are going to inject into (the injection site) with rubbing alcohol. Change the injection site each time to lessen injury under the skin. Do not inject into scars, stretch marks, or skin that is tender, bruised, red, or hard. To lessen bruising, do not rub the injection site after a shot. Learn how to store and discard medical supplies safely.
Use this medication regularly to get the most benefit from it. To help you remember, use it on the same day each week. Mark your calendar with a reminder.
Tell your doctor if your condition does not get better or if it gets worse.
Redness, itching, swelling, hardening, bruising, or pain at the injection site may occur. Headache may also occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.
Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
This medication may rarely cause serious (sometimes fatal) problems from blood clots (such as pulmonary embolism, stroke, heart attack, deep vein thrombosis). You may be at increased risk for blood clots if you are also using other products (such as Factor VIII or IX). Get medical help right away if you develop symptoms of serious blood clots, such as shortness of breath/rapid breathing, chest/jaw/left arm pain, unusual sweating, confusion, sudden dizziness/fainting, pain/swelling/warmth in the groin/calf, sudden/severe headaches, trouble speaking, weakness on one side of the body, sudden vision changes.
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Before using marstacimab, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of:
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products). Your doctor or dentist may tell you to stop using marstacimab before your surgery. Ask for specific instructions about stopping or starting this medication.
Tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while using marstacimab. Marstacimab may harm an unborn baby. Your doctor should order a pregnancy test before you start this medication. Ask about reliable forms of birth control while using this medication and for 2 months after the last dose. If you become pregnant, talk to your doctor right away about the risks and benefits of this medication.
It is unknown if this medication passes into breast milk. Consult your doctor before breastfeeding.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.
Do not share this medication with others.
Lab and/or medical tests (such as blood clotting tests) must be done while you are using this medication. Keep all medical and lab appointments.
It is important to get each dose of this medication as scheduled. If you miss a dose, ask your doctor or pharmacist right away for a new dosing schedule. Do not double the dose to catch up.
Store in the refrigerator. Do not shake or freeze. Keep the medication in the original package to protect it from light. This medication may also be stored at room temperature if needed. If the medication is stored at room temperature, do not put it back in the refrigerator and discard after 7 days. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Your condition can cause complications in a medical emergency. For information about enrolling in MedicAlert, call 1-888-633-4298 (US) or 1-800-668-1507 (Canada).
HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
Information last revised November 2024.
Copyright(c) 2025 First Databank, Inc.
Selected from NATIONAL DRUG DATA FILE (NDDF) data included with permission and copyrighted by First Databank, Inc., 2019. This copyrighted material has been downloaded from a licensed data provider.
The above information is intended to supplement, not substitute for, the expertise and judgment of your health care professional. You should consult your health care professional before taking any drug, changing your diet, or commencing or discontinuing any course of treatment.