Hemophilia A is a genetic condition that makes it hard for blood to clot properly. This happens because the body does not have enough of a protein called Factor VIII, which helps stop bleeding. The main goal of treating someone with hemophilia is to stop and prevent bleeding by giving them the missing Factor VIII. This treatment can be given when a person starts bleeding (called on-demand treatment), or it can be given regularly to prevent bleeding (called prophylactic therapy). In India, most people with hemophilia A get treatment only when they have a bleeding episode, and only a few receive regular preventive treatment. Octocog alfa (also known as BAY 81-8973) is a modern, laboratory-made version of Factor VIII. It is made without using any human or animal materials and has special features that help it work better in the body. In India, Octocog alfa is approved for use in adults and children with hemophilia A to:

• Treat and control bleeding episodes when they happen
• Manage bleeding during surgery
• Prevent bleeding by giving regular treatment The safety and effectiveness of Octocog alfa have been shown in several global studies. This new study is required by Indian health authorities to collect information about how safe Octocog alfa is and how well it works in people with hemophilia A who have already received treatment. The study will look at how Octocog alfa is used in real-life medical practice in India, including how doctors prescribe it, how patients use it, and what treatment results they have.

Inclusion Criteria:

• Male patients aged 18 years or older with a documented diagnosis of severe Hemophilia A, defined by a baseline Factor VIII (FVIII) activity level of less than 1% (<0.01 IU/mL) in accordance with the Hemophilia Severity Classification
• Previously treated with FVIII concentrate(s) (plasma derived or recombinant, including Octocog alfa) either on-demand or prophylactically for at least 100 Exposure Days (EDs).
• Patients for whom the decision to initiate on-demand treatment with Octocog alfa for acute bleeding was made as per the investigator's routine treatment practice. This will include patients who are already on on-demand treatment with Octocog alfa as well.
• Written informed consent from the patient or legal representative

Exclusion Criteria:

• Known contraindication according to the local prescriber information
• Patients who are participating in an investigational program with interventions outside of routine clinical practice.
• Patients with any other diagnosis of bleeding/coagulation disorder other than Hemophilia A.
• Patients who are on ongoing prophylactic treatment with any FVIII concentrate or non-factor treatments like emicizumab.
• Patients exhibiting any of the following laboratory abnormalities at screening:
• Known platelet count <100,000 mm3
• Known Serum Creatinine >2 folds upper the normal limit
• Known Hepatic AST or ALT >5 folds upper the normal limit
• Patients who have received an on-demand infusion with any other FVIII (different to Octocog alfa), FVII or Activated prothrombin complex concentrate product (aPCC/FEIBA) 72 hours before the enrollment.
• History or presence of FVIII inhibitor with a titer ≥ 0.6 with Nijmegen modified Bethesda Assay (NBA), or a clinical history suggestive of an inhibitor necessitating changes to treatment
• Patient concerns or other barriers precluding adequate understanding or cooperation.

Male adult patients (aged ≥18 years) with severe Hemophilia A in India, who have been previously treated for at least 100 exposure days to FVIII concentrate(s) and are prescribed Octocog alfa for managing bleeding episodes

Currently, there is no established plan for the sharing of Individual Patient Data (IPD) from this study. The availability of this study's data will later be determined according to Bayer's commitment to the EFPIA/PhRMA 'Principles for responsible clinical trial data sharing.' This pertains to the scope, timepoint, and process of data access. As such, Bayer commits to considering requests from qualified researchers for patient- / study-level clinical trial data, and documents from clinical trials involving medicines and indications approved in the US and EU. However, this commitment does not reflect an active IPD sharing plan. This applies to data on new medicines and indications that have been approved by the EU and US regulatory agencies on or after January 01, 2014. Researchers can use www.vivli.org to request access to IPD and documents from clinical studies to conduct research. Information on Bayer's criteria for listing studies is provided in the member section of the portal.