A Long-Term Follow-Up Study in Severe Hemophilia A Subjects Who Received BMN 270 in a Prior BioMarin Clinical Trial (270-401)

Inclusion Criteria: * Participants must have completed their primary treatment study or be currently enrolled in the primary treatment study at the time of closure by the Sponsor. Participants may enroll in 270-401 even if they have restarted FVIII prophylaxis or other hemophilia A treatment. * Subjects must be capable of giving signed informed consent, which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol. If the subject is unable to provide consent, a legally authorized representative may provide written informed consent. Exclusion Criteria: * Participants who do not directly enroll in 270-401 at the time of the study completion visit in their primary treatment study should enroll in 270-401 within 4 months of the date of that study completion visit. If a participant wishes to enroll in 270-401 after 4 months, they must receive prior approval from the Medical Monitor. * Participants must be overtly healthy and not have any condition that, in the opinion of the Investigator or Medical Monitor, would prevent the participant from fully complying with the requirements of the study and/or would impact or interfere with evaluation and interpretation of the study data (including, if applicable, advanced HIV disease). * Where applicable, per country regulation, the participant must not currently be committed to an institution by virtue of an order issued either by judicial or administrative authorities.