(marstacimab-hncq)
For subcutaneous use only.
The recommended dosage of HYMPAVZI for adults and pediatric patients 12 years of age and older is as follows:
Loading Dose
300 mg (two 150 mg subcutaneous injections)
If more than one injection is required to deliver a complete dose, administer each injection at a different injection site.
Maintenance Dose
One week after the loading dose, initiate maintenance dosing of 150 mg every week by subcutaneous injection on the same day each week, at any time of day.
Dose Adjustment During Treatment
In patients weighing greater than or equal to 50 kg, consider a dose adjustment to 300 mg subcutaneous injection weekly when control of bleeding events is judged to be inadequate by the healthcare provider. Safety and efficacy of HYMPAVZI at doses above 300 mg weekly have not been established.
If more than one injection is required to deliver a complete dose, administer each injection at a different injection site.
Missed Doses
For patients on a maintenance dose of 150 mg:
If a dose is missed, administer as soon as possible before the day of the next scheduled dose, and then resume usual 150 mg subcutaneous weekly dosing schedule (same schedule as prior to the missed dose or new schedule based on date of administration of missed dose).
If more than 13 days have passed since the last dose was administered, administer a loading dose of 300 mg by subcutaneous injection followed by a resumption of 150 mg by subcutaneous injection once weekly thereafter.
For patients on a maintenance dose of 300 mg:
If one or more doses are missed, administer a dose as soon as possible, and then resume 300 mg subcutaneous weekly dosing schedule (same schedule as prior to the missed dose or new schedule based on date of administration of missed dose).
For subcutaneous use only.
The recommended dosage of HYMPAVZI for pediatric patients 6 to less than 12 years of age is as follows:
Loading Dose
150 mg (one 150 mg subcutaneous injection or two 75 mg subcutaneous injections)
If more than one injection is required to deliver a complete dose, administer each injection at a different injection site.
Maintenance Dose
One week after the loading dose, initiate maintenance dosing of 75 mg every week by subcutaneous injection on the same day each week, at any time of day.
Dose Adjustment During Treatment
In patients weighing greater than or equal to 25 kg, consider a dose adjustment to 150 mg subcutaneous injection (one 150 mg subcutaneous injection or two 75 mg subcutaneous injections) weekly when control of bleeding events is judged to be inadequate by the healthcare provider. Safety and efficacy of HYMPAVZI at doses above 150 mg weekly have not been established in children 6 to less than 12 years of age.
If more than one injection is required to deliver a complete dose, administer each injection at a different injection site.
Missed Doses
For patients on a maintenance dose of 75 mg:
If a dose is missed, administer as soon as possible before the day of the next scheduled dose, and then resume usual 75 mg subcutaneous weekly dosing schedule (same schedule as prior to the missed dose or new schedule based on date of administration of missed dose).
If more than 13 days have passed since the last dose was administered, administer a loading dose of 150 mg by subcutaneous injection followed by a resumption of 75 mg by subcutaneous injection once weekly thereafter.
For patients on a maintenance dose of 150 mg:
If one or more doses are missed, administer a dose as soon as possible, and then resume 150 mg subcutaneous weekly dosing schedule (same schedule as prior to the missed dose or new schedule based on date of administration of missed dose).
Changing from prophylactic factor replacement therapy or bypassing agents to HYMPAVZI: Prior to initiation of HYMPAVZI, discontinue treatment with clotting factor concentrates (factor VIII or factor IX concentrates) or bypassing agents (e.g., recombinant FVIIa [rFVIIa] or activated prothrombin complex concentrate [aPCC]). HYMPAVZI can be initiated at any time after discontinuing clotting factor concentrates or bypassing agents.
No data are available in patients changing from other non-factor-based hemophilia medicinal products to HYMPAVZI.
Factor VIII and factor IX products or bypassing agents (e.g., rFVIIa or aPCC) can be administered for the treatment of breakthrough bleeds in patients receiving HYMPAVZI. Do not use additional doses of HYMPAVZI to treat breakthrough bleeds. Healthcare providers should discuss with all patients and/or caregivers the dose and schedule of the clotting factor concentrates or bypassing agents to use, if required, while receiving HYMPAVZI prophylaxis.
When treating breakthrough bleeds with factor VIII or factor IX products or with bypassing agents, the lowest effective dose according to the product prescribing information is recommended [see Warnings and Precautions (5.1)]. Please refer to the Full Prescribing Information for the clotting factor concentrate or bypassing agent being used. For rFVIIa, a maximum dose of 90 mcg/kg body weight per dose and a maximum dosing frequency of every 2 hours is recommended. For aPCC, a maximum dose of 100 units/kg body weight within 24 hours is recommended.
Management in the Perioperative Setting
HYMPAVZI has not been evaluated in the setting of major surgery. Patients have had minor surgical procedures without discontinuing HYMPAVZI prophylaxis in clinical studies.
For major surgery, pause HYMPAVZI at least 7 days prior and initiate management per local standard of care with clotting factor concentrate or bypassing agent and measures to manage the risk of venous thrombosis which can be elevated in the perioperative period. Consult the product information for the clotting factor concentrate or bypassing agent for dosage guidelines in patients with hemophilia undergoing major surgery. Resumption of HYMPAVZI therapy should consider the overall clinical status of the patient, including the presence of post-surgical thromboembolic risk factors, use of other hemostatic products and other concomitant medications [see Dosage and Administration (2.1)].
Management in Patients with Acute Severe Illness
There is limited experience with the use of HYMPAVZI in patients with acute severe illness. Reasons to consider temporary dose interruption of HYMPAVZI include occurrence of acute severe illness (e.g., serious infection, sepsis, trauma) in which there may be increased activation of coagulation and which the healthcare provider considers could increase the risks associated with HYMPAVZI administration. Treatment of acute severe illness should be managed per local standard of care, and continued treatment with HYMPAVZI in this situation should be weighed against the potential risks involved. Resume HYMPAVZI therapy once patient has clinically recovered [see Dosage and Administration (2.1)].
Verify that females of reproductive potential are not pregnant prior to initiating HYMPAVZI [see Warnings and Precautions (5.3), Use in Specific Populations (8.1, 8.3)].
The safety and efficacy of HYMPAVZI in patients receiving ongoing Immune Tolerance Induction (ITI), a desensitization strategy for the eradication of inhibitors, have not been established, and no data are available. Careful assessment of the potential benefits and risks should be performed if continuation or initiation of HYMPAVZI during ITI is considered.
| This Patient Information has been approved by the U.S. Food and Drug Administration. Revised: 6/2026 | |||
PATIENT INFORMATION HYMPAVZI® (him-PAV-zee) (marstacimab-hncq) injection, for subcutaneous use | |||
Important information:
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What is HYMPAVZI? HYMPAVZI is a prescription medicine used regularly to prevent or reduce the frequency of bleeding episodes in adults and children 6 years of age and older with:
It is not known if HYMPAVZI is safe and effective in people receiving ongoing Immune Tolerance Induction (ITI). It is not known if HYMPAVZI is safe and effective in children younger than 6 years of age. | |||
Before using HYMPAVZI, tell your healthcare provider about all of your medical conditions, including if you:
Tell your healthcare provider about all the medicines you take, including prescription medicines, over‑the‑counter medicines, vitamins, and herbal supplements. Know the medicines you take. Keep a list of them to show your healthcare provider and pharmacist when you get a new medicine. | |||
How should I use HYMPAVZI? See the detailed “Instructions for Use” that comes with your HYMPAVZI for information on how to inject a dose of HYMPAVZI, and how to properly throw away (dispose of) used HYMPAVZI prefilled syringe or HYMPAVZI prefilled pen.
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What are the possible side effects of HYMPAVZI? HYMPAVZI may cause serious side effects, including:
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The most common side effects of HYMPAVZI include: | |||
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These are not all of the possible side effects of HYMPAVZI. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. | |||
How should I store HYMPAVZI?
Keep HYMPAVZI and all medicines out of the reach of children. | |||
General information about the safe and effective use of HYMPAVZI. Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. Do not use HYMPAVZI for a condition for which it was not prescribed. Do not give HYMPAVZI to other people, even if they have the same symptoms that you have. It may harm them. You can ask your pharmacist or healthcare provider for information about HYMPAVZI that is written for health professionals. | |||
What are the ingredients in HYMPAVZI? Active ingredient: marstacimab‑hncq Inactive ingredients: edetate disodium, histidine, L-histidine monohydrochloride, polysorbate 80, sucrose, and water for injection | |||
This product's labeling may have been updated. For the most recent prescribing information, please visit www.pfizer.com.
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