Last reviewed 2026-04-20 · How we verify

Alhemo (CONCIZUMAB)

Alhemo works by blocking the activation of blood clotting factors to prevent excessive bleeding in people with hemophilia.

Alhemo (concizumab) is a monoclonal antibody developed by Novo Nordisk Inc, targeting the tissue factor pathway to inhibit blood clotting. It is approved for the treatment of hemophilia A and B, with or without inhibitors, and works by blocking the activation of blood clotting factors. Alhemo is a patented product with a commercial status, and its safety considerations include potential allergic reactions and increased risk of bleeding. The exact mechanism of action involves binding to and inhibiting the activity of tissue factor pathway inhibitor (TFPI) to prevent the activation of coagulation factors. Alhemo was FDA-approved in 2024 for its approved indications.

At a glance

Mechanism of action

Concizumab-mtci is a monoclonal antibody antagonist of endogenous Tissue Factor Pathway Inhibitor (TFPI). Through the inhibition of TFPI, concizumab-mtci acts to enhance FXa production during the initiation phase of coagulation which leads to improved thrombin generation and clot formation with the goal of achieving hemostasis in patients with Hemophilia A or B regardless of their inhibitor status. The effect of concizumab-mtci is not influenced by the presence of inhibitory antibodies to FVIII or FIX. There is no structural relationship or sequence homology between concizumab-mtci and FVIII or FIX and, as such, treatment with concizumab-mtci does not induce or enhance the development of direct inhibitors to FVIII or FIX.

Approved indications

• hemophilia A (congenital factor VIII deficiency)
• hemophilia A (congenital factor VIII deficiency) with or without FVIII inhibitors
• hemophilia B (congenital factor IX deficiency)
• hemophilia B (congenital factor IX deficiency) with or without FIX inhibitors

Common side effects

• Injection site reactions
• Urticaria
• Headache
• Injection site bruising
• Injection site erythema
• Injection site hematoma
• Injection site hemorrhage
• Injection site rash
• Injection site nodule

Drug interactions

• Alhemo
• FVIII
• FIX
• rFVIIa
• aPCC
• Alhemo
• FVIII
• FIX
• rFVIIa
• aPCC
• Alhemo
• concizumab-mtci

Key clinical trials

• Research Study to Look at How Well the Drug Concizumab Works in Your Body if You Have Haemophilia With Inhibitors (PHASE3)
• Research Study to Look at How Well the Drug Concizumab Works in Your Body if You Have Haemophilia Without Inhibitors (PHASE3)
• Compassionate Use of Concizumab if You Have Haemophilia
• A Research Study on How Well Concizumab Works for You if You Have Haemophilia A or B With or Without Inhibitors (PHASE3)
• Post-marketing Surveillance (Special Use-results Surveillance) on Treatment With Alhemo
• Post-Marketing Surveillance (All Case Surveillance) on Treatment With Alhemo® in Patients With Haemophilia A or Haemophilia B With Inhibitors
• In Vitro Correction of Thrombin Generation by Concizumab (Anti-TFPI) for Severe Hemophilia Patients
• Targeting TFPI With Concizumab to Improve Haemostasis in Glanzmann Thrombasthenia Patients: an in Vitro Study (NA)

Primary sources

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