Research Study to Look at How Well the Drug Concizumab Works in Your Body if You Have Haemophilia With Inhibitors

Brief summary (registry, in English)

This study will test how well a new medicine called concizumab works in the body of people with haemophilia A or B with inhibitors. The purpose is to show that concizumab can prevent bleeds in the body and is safe to use. Participants who usually only take medicine to treat bleeds (on-demand) will be placed in one of two groups. In one group, participants will get study medicine from the start of the study. In the other group, participants will continue with their normal medicine and get study medicine after 6 months. Which treatment the participant gets is decided by chance. Participants who usually take medicine to prevent bleeds (prophylaxis treatment) or who are already being treated with concizumab (study medicine) will receive the study medicine from the start of the study. Participants will get 1 injection with the study medicine every day under the skin. This participants will have to do themselves and can be done at home. The study doctor will hand out the medicine in the form of a pen-injector. The pen-injector will contain the study medicine. The study will last for about seven years. The length of time the participants will be in the study depends on when they agreed to take part or when the medicine is available for purchase in their country (31 December 2026 at the latest). The time between visits will be approximately 4 weeks for the first 6 to 12 months, depending on the group participants are in and approximately 8 weeks for the rest of the study. Participants will be asked to record information into an electronic diary during the study and may also be asked to wear an activity tracker.

What you commit to

• Study type: Interventional · Phase 3
• Participants enrolled: 134
• From 21 Oct 2019 to the primary completion date, 27 Dec 2021
• 85 sites in 29 countries
• Visits and tests: ask the trial team, the registry does not list them

Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.

Who cannot take part

Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.

Who the study is looking for

Sex: Male · Does not accept healthy volunteers

Full criteria on ClinicalTrials.gov

Sites (85)

Sites in registry order. Pick your city on the disease page to sort them by distance.

Related publications

• Concizumab in hemophilia with inhibitors: longer-term efficacy and safety results from the phase 3 explorer7 study.Blood Adv · 2026 · PMID 41499759