Overview
11 DESCRIPTION Marstacimab‑hncq is a tissue factor pathway inhibitor (TFPI) antagonist, human monoclonal immunoglobulin G Type 1 (IgG1) antibody. Marstacimab‑hncq is produced by Chinese hamster ovary (CHO) cells by recombinant DNA technology and has a molecular mass of approximately 146 kDa.
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Marstacimab‑hncq is a human monoclonal IgG1 antibody directed against the Kunitz domain 2 (K2) of TFPI to neutralize TFPI activity and enhance coagulation. TFPI is the primary inhibitor of the extrinsic coagulation cascade and negatively regulates thrombin generation within the extrinsic pathway of coagulation by inactivating the protease functions of FXa/FVIIa/TF complex. TFPI binds to and inhibits the factor Xa active site via its second Kunitz inhibitor domain (K2). 12.2 Pharmacodynamics Marstacimab‑hncq causes an increase in total TFPI (comprised of free TFPI and TFPI bound to marstacimab) and downstream biomarkers of thrombin generation such as prothrombin fragments 1+2, peak thrombin, and D‑Dimer in patients with hemophilia.
Indications
- 1 INDICATIONS AND USAGE HYMPAVZI is indicated for routine prophylaxis to prevent or reduce the frequency of bleeding episodes in adult and pediatric patients 12 years of age and older with: • hemophilia A (congenital factor VIII deficiency) without factor VIII inhibitors, or • hemophilia B (congenital factor IX deficiency) without factor IX inhibitors. HYMPAVZI is a tissue factor pathway inhibitor (TFPI) antagonist indicated for routine prophylaxis to prevent or reduce the frequency of bleeding episodes in adult and pediatric patients 12 years of age and older with: • hemophilia A (congenital...
Common Doses
- 300 mg
- 150 mg
Dosage
2 DOSAGE AND ADMINISTRATION • See Full Prescribing Information for important dosing and administration instructions. ( 2.1 , 2.2 , 2.3 , 2.4 , 2.5 , 2.6 ) • The recommended dosage of HYMPAVZI is: o Loading dose: 300 mg (two 150 mg injections) by subcutaneous injection o 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. ( 2.1 ) • Dose adjustment to 300 mg subcutaneous injection weekly can be considered. ( 2.
Contraindications
- 4 CONTRAINDICATIONS None. None. ( 4 )
Side Effects
- 6 ADVERSE REACTIONS The following clinically significant adverse reactions are described elsewhere in the labeling: • Thromboembolic Events [see Warnings and Precautions (5.1) ] • Hypersensitivity [see Warnings and Precautions (5.2) ] Adverse reactions reported in ≥3% of HYMPAVZI-treated patients were injection site reaction, headache, and pruritus. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Pfizer Inc. at 1-800-438-1985 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.
Interactions
- 7 DRUG INTERACTIONS Partial Thromboplastin Time (aPTT) and Prothrombin Time (PT) No clinically significant differences in standard measures of coagulation including activated partial thromboplastin time (aPTT) and prothrombin time (PT) were observed following marstacimab‑hncq therapy.