(marstacimab-hncq)

Prescribing Information
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2 DOSAGE AND ADMINISTRATION

2 DOSAGE AND ADMINISTRATION

    

2.1 Recommended Dosage in Adults and Pediatric Patients 12 Years of Age and Older

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).

2.2 Recommended Dosage in Pediatric Patients 6 to less than 12 Years of Age

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).

2.3 Preparation and Administration

HYMPAVZI is intended for use under the guidance of a healthcare provider. After proper instruction in subcutaneous injection technique, a patient 12 years and older may self-inject or the patient’s caregiver may administer HYMPAVZI, if a healthcare provider determines that it is appropriate.
Refer to the Instructions for Use for complete preparation and administration instructions.
Prior to subcutaneous administration, HYMPAVZI may be removed from the refrigerator and allowed to warm at room temperature [up to 86°F (30°C)] in the carton for 15 to 30 minutes protected from direct sunlight. Do not warm by using a heat source such as hot water or a microwave. After removal of HYMPAVZI from the refrigerator, use within 7 days or discard [see How Supplied/Storage and Handling (16)].
Administer HYMPAVZI by subcutaneous injection, once weekly, at any time of the day in the abdomen or front of thigh. Other injection sites are acceptable if required. Administration of HYMPAVZI in the back of upper arm (prefilled syringe only) or buttocks (prefilled pen only) should be performed by a caregiver or healthcare professional only. HYMPAVZI should not be administered into bony areas or areas where the skin is bruised, red, tender or hard, or areas where there are scars or stretch marks. HYMPAVZI should not be injected into a vein. Rotate the injection site with each new injection.
During treatment with HYMPAVZI, other medicinal products for subcutaneous administration should, preferably, be injected at different anatomical sites.
Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. HYMPAVZI is a clear and colorless to light yellow solution. Do not use if the solution is cloudy, dark yellow, or contains flakes or particles.

2.4 Changing to HYMPAVZI

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.

2.5 Guidance on Use with Breakthrough Bleed Treatments

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.

2.6 Temporary Interruption for Surgery and Other Interventions

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)].

2.7 Pregnancy Testing

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)].

2.8 Immune Tolerance Induction

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.

Medication Guide

MEDICATION GUIDE

     

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:

Before you start using HYMPAVZI, it is very important to talk to your healthcare provider about using factor VIII and factor IX products or bypassing agents (products that help blood clot but work in a different way than HYMPAVZI).
Your healthcare provider may prescribe factor VIII, factor IX medicines, or bypassing agents to treat episodes of breakthrough bleeding during your treatment with HYMPAVZI. Carefully follow your healthcare provider’s instructions regarding when to use these medicines and the prescribed dose during your treatment with HYMPAVZI. Do not use additional doses of HYMPAVZI to treat breakthrough bleeds.

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:

hemophilia A with or without factor VIII inhibitors, or
hemophilia B with or without factor IX inhibitors.

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:

have a planned surgery. Your healthcare provider may stop treatment with HYMPAVZI before your surgery. Talk to your healthcare provider about when to stop using HYMPAVZI and when to start it again if you have a planned surgery.
have a severe short-term (acute) illness such as an infection or injury.
have been told that you have a risk for blood clots.
are pregnant or plan to become pregnant. HYMPAVZI may harm your unborn baby.
 
Females who are able to become pregnant:
o
Your healthcare provider will do a pregnancy test before you start your treatment with HYMPAVZI.
o
Use effective birth control (contraception) during treatment with HYMPAVZI and for 2 months after the last dose of HYMPAVZI.
o
Tell your healthcare provider right away if you become pregnant or think that you may be pregnant during treatment with HYMPAVZI.
are breastfeeding or plan to breastfeed. It is not known if HYMPAVZI passes into your breast milk.

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.

Use HYMPAVZI exactly as prescribed by your healthcare provider.
Your healthcare provider will provide instructions for stopping (discontinuing) your current treatment when switching from factor- or non-factor-based medicines or bypassing agents to HYMPAVZI.
HYMPAVZI comes in two different strengths in a single-dose prefilled syringe or single-dose prefilled pen.
HYMPAVZI is given as an injection under your skin (subcutaneous injection) by you or your caregiver.
People 12 years of age and older, or their caregiver may inject HYMPAVZI if your healthcare provider decides that it is appropriate. Your healthcare provider should show you or your caregiver how to inject HYMPAVZI before the first injection.
Do not inject yourself or someone else until you have been shown how to inject HYMPAVZI.
Inject HYMPAVZI 1 time a week on the same day each week. Inject HYMPAVZI at any time of day.
Dosing for adults and children 12 years of age and older:
o
Your first dose (loading dose) of HYMPAVZI is 300 mg (two 150 mg injections). Then you will inject a weekly (maintenance) dose as prescribed by your healthcare provider.
o
If you miss a maintenance dose of 150 mg of HYMPAVZI:
Give the dose as soon as possible before the day of your next scheduled dose, and then continue with your usual weekly dosing schedule. You may inject your next dose at your regularly scheduled time or continue dosing based on the new day you injected your missed dose. In case you are not sure when to inject HYMPAVZI, call your healthcare provider.
If more than 13 days have passed since your last dose was given, you will need to restart with a loading dose. Call your healthcare provider right away for dosing instructions.
o
If you miss 1 or more doses of maintenance dose of 300 mg of HYMPAVZI:
Give a dose as soon as possible, and then continue with your usual weekly dosing schedule. You may inject your next dose at your regularly scheduled time or continue dosing based on the new day you injected your missed dose. In case you are not sure when to inject HYMPAVZI, call your healthcare provider.
Dosing for children 6 years to less than 12 years of age:
o
Your first dose (loading dose) of HYMPAVZI is 150 mg (one 150 mg injection or two 75 mg injections) as prescribed by your healthcare provider. Then you will inject a weekly (maintenance) dose as prescribed by your healthcare provider.
o
If you miss a maintenance dose of 75 mg of HYMPAVZI:
Give the dose as soon as possible before the day of your next scheduled dose, and then continue with your usual weekly dosing schedule. You may inject your next dose at your regularly scheduled time or continue dosing based on the new day you injected your missed dose. In case you are not sure when to inject HYMPAVZI, call your healthcare provider.
If more than 13 days have passed since your last dose was given, you will need to restart with a loading dose. Call your healthcare provider right away for dosing instructions.
o
If you miss 1 or more doses of maintenance dose of 150 mg of HYMPAVZI:
Give a dose as soon as possible, and then continue with your usual weekly dosing schedule. You may inject your next dose at your regularly scheduled time or continue dosing based on the new day you injected your missed dose. In case you are not sure when to inject HYMPAVZI, call your healthcare provider.
If you inject too much HYMPAVZI, call your healthcare provider or the Poison Help Line at 1-800-222-1222 or go to the nearest hospital emergency room right away.

What are the possible side effects of HYMPAVZI?

HYMPAVZI may cause serious side effects, including:

blood clots (thromboembolic events). HYMPAVZI may increase the risk for your blood to clot in blood vessels in your arm, leg, lung, or head and can be life-threatening. Blood clots have happened in people using HYMPAVZI. You may have an increased risk of blood clots if you have certain risk factors. Stop using HYMPAVZI and get medical help right away if you develop any of these signs or symptoms of blood clots:
o
swelling or pain in arms or legs
o
redness or discoloration in your arms or legs
o
shortness of breath
o
pain in chest or upper back
o
fast heart rate
o
cough up blood
o
feel faint
o
headache
o
numbness in your face
o
eye pain or swelling
o
trouble seeing
allergic reactions. HYMPAVZI may cause allergic reactions, including rash and itching. Stop using HYMPAVZI and get medical help right away if you develop any of the following symptoms of a severe allergic reaction:
o
swelling of your face, lips, mouth, or tongue
o
trouble breathing
o
wheezing
o
dizziness or fainting
o
fast heartbeat or pounding in your chest
o
sweating

The most common side effects of HYMPAVZI include:

swelling, hardening, redness, bruising, bleeding, and pain at injection site
headache
fever
joint pain
diarrhea
itching
rash

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?

Store HYMPAVZI in a refrigerator at 36°F to 46°F (2°C to 8°C).
Store HYMPAVZI in the original carton to protect from light.
If needed, HYMPAVZI may be stored one time at room temperature up to 86°F (30°C) in its original carton for up to 7 days. Do not return HYMPAVZI to the refrigerator after storing at room temperature.
Throw away (dispose of) HYMPAVZI that has been left out of the refrigerator for more than 7 days.
Do not freeze HYMPAVZI.
Do not shake 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.

Pfizer logo
US License No. 2001
Distributed by: Pfizer Labs, Division of Pfizer Inc., New York, NY 10001
LAB-1575-3.0
For more information, go to website www.HYMPAVZI.com or call 1-800-438-1985.

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