This is a multinational, prospective, open-label, roll-over study in patients with haemophilia A, ≥6 years of age, who have completed participation in any of the parental studies with efanesoctocog alfa; XTEND-ed study (LTS16294), FREEDOM study (Sobi.BIVV001-001), PK comparison study (Sobi.BIVV001-003) or SHINE study (Sobi.BIVV001-004). The aim of the study is to provide patients with continuous benefit from efanesoctocog alfa treatment and to further continue clinical monitoring for safety and efficacy until efanesoctocog alfa is commercially available in each patient's respective country (or until March 2027, whichever comes first).

The study starts with the Baseline Visit, which will be done in connection to the end of treatment at the EoT/EoS visit (or equivalent) in the respective parent study. Subsequent study visits (on site or phone call) will be done approximately every 13 weeks until End of Treatment. An End of Study safety phone call will be done 14 (+7) days after the End of Treatment Visit.

Inclusion Criteria:

• Capable of giving signed informed consent. Parents or legally designated representatives' consent is required for patients who are below 18 years of age or unable to give consent. Patients who are below 18 years of age may provide assent in addition to the parents'/legally designated representatives' consent, if appropriate.
• Must have completed one of the required parent studies: Sobi.BIVV001-001, Sobi.BIVV001-003, LTS16294, or Sobi.BIVV001-004, and be receiving a clinical benefit from the efanesoctocog alfa treatment, as judged by the Investigator.
• Willingness and ability of patient or their parent or legally designated representative to complete training in the use of the study patient diary and to complete the diary throughout the study.

Exclusion Criteria:

• Positive inhibitor result, defined as ≥0.6 Bethesda units (BU)/mL, present at the Baseline Visit.
• Ongoing or planned participation in any interventional clinical study at the Baseline Visit.
• Patient not suitable for participation, whatever the reason, as judged by the Investigator, including medical or clinical conditions, or patients potentially at risk of noncompliance to study procedures.

Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sobi data sharing criteria and process for requesting access can be found at: https:// www.sobi.com/en/policies

Within 1 year following completion of the trial, or at the time of CSR finalization.

A decision on sharing will be based on the following:

The scientific merit of the proposal - i.e. the proposal should be scientifically sound, ethical, and have the potential to contribute to the advancement of public health. The feasibility of the research proposal - i.e. the requesting research team must be scientifically qualified and have the resources to conduct the proposed project. Maintenance of personal integrity - i.e. Sobi will not consider sharing individual data if there is a risk of re-identification of individuals despite a proper anonymisation. Moreover, the patients' informed consent will always be respected. Sobi reserves the right to reject the proposal if the anonymisation process will render unusable data. Publication of results - the applicants should commit to submit their findings to a peer-reviewed scientific journal, alternatively to present the results at a congress (poster or similar), regardless of the research outcome.