Elocta (rFVIIIFc) and Alprolix (rFIXFc) are recombinant extended half-life coagulation factor products. The purpose of this non-interventional study is to describe the real-world usage and effectiveness of Elocta and Alprolix in the prophylactic treatment of haemophilia A and B.

Inclusion Criteria:

• Have a diagnosis of haemophilia A or B and previously treated with factor Product
• Have started prophylactic Elocta/Alprolix treatment prior to enrollment visit, or at enrollment prescribed prophylactic treatment with Elocta or Alprolix regardless of participation in the study
• Signed and dated informed consent provided by the patient, or the patient's legally acceptable representative for patients under the legal age, Before any study-related activities are undertaken. Assent should be obtained from paediatric patients according to local regulations.

Exclusion Criteria:

• Participation in an investigational medicinal product trial, from four weeks prior to first injection with Elocta or Alprolix to enrollment visit.

All eligible Elocta and Alprolix patients who present for a routine Clinical visit will be asked to participate in the study by the treating physician at participating haemophilia treatment centres in Germany.