Study of Modified Recombinant Factor VIII (OBI-1) in Subjects With Acquired Hemophilia A

Inclusion Criteria: * Written informed consent from subject, trusted person or person who is legally authorized to sign on behalf of the participant (Legal Representative in U.S.), depending on local regulations * Participants with acquired hemophilia with autoimmune inhibitory antibodies to human factor VIII with a clinical diagnosis established by the following criteria: a) Prolonged activated partial thromboplastin time (aPTT), b) Prothrombin time (PT) ≤ upper limit of normal (ULN) + 2 seconds and platelet count within normal range, c) Abnormal aPTT mixing study (patient-normal control 1:1) consistent with a factor VIII inhibitors reduced factor VIII activity level (below 10%) * Has a serious bleeding episode, as documented by the investigator * Be willing and able to follow all instructions and attend all study visits * Participants taking anti-thrombotics (such as clopidogrel, heparin or heparin analogue) may be included provided three half-lives of the agent have elapsed since the last dose of the agent * Life expectancy, prior to onset of the hemorrhagic episode, of at least 90 days * Participants of reproductive age must use acceptable methods of contraception and if female, undergo pregnancy testing as part of the screening process Exclusion Criteria: * Hemodynamically unstable after blood transfusion, fluid resuscitation and pharmacologic or volume replacement pressor therapy. This hemodynamic instability is characterized by symptomatic hypotension resulting in v…