Pharmacokinetic, Efficacy and Safety of BT524 in Patients With Congenital Fibrinogen Deficiency

Inclusion Criteria: * Known congenital afibrinogenemia or severe congenital hypofibrinogenemia * Plasma fibrinogen activity ≤ 0.5 g/l and antigen ≤ 0.5 g/l * Male or female * Age 0 to 75 years, with the first ten patients will be 18 years or older * Presumed to be compliant with the study procedures and to terminate the study as scheduled * Willing and able to be hospitalized for 3 days for the pharmacokinetic assessment (if applicable) * Willing and able to be hospitalized - if required - in case of interventions (e.g., surgical procedures, major bleeds) * Written informed consent by the patient, his/her parents or by the patient's legal/authorized representative as applicable Exclusion Criteria: * Known congenital dysfibrinogenemia (not applicable for adult patients with hypodysfibrinogenemia in study part II) * Known bleeding disorder other than congenital fibrinogen deficiency * History of esophageal variceal bleeding * Known presence or history of venous/arterial thrombosis or thromboembolic event in the preceding 6 months * Known presence or history of fibrinogen inhibitory antibodies * Known presence or history of hypersensitivity to human fibrinogen or human plasma proteins e.g., immunoglobulins, vaccines or hypersensitivity to any of the excipients * Known positive serology for HIV-1 and HIV-2 * Clinically relevant biochemical or hematological findings (except due to underlying disease or emergency bleeding) outside the normal range (at the investigator's discreti…