Summary. Acquired haemophilia is a life-threatening disorder caused by circulating auto-antibodies that inhibit factor VIII coagulant activity (FBIII:C). Immunoadsorption on protein A sepharose (IA-PA) was performed in two bleeding patients with acquired haemophilia: we observed a dramatic and quick decrease in the anti-FVIII:C inhibitor titre leading to a normal, albeit transient, haemostatic status. In one case, IA-PA was the only procedure which succeeded in stopping massive haemorrhage. In the second case, IA-PA reinforced the haemostatic effect of recombinant activated factor VII by increasing the endogenous plasma factor VIII level. The efficacy of IA-PA was sustained with immunosuppressive treatment introduced, respectively, 10 and 15 d before the IA-PA procedures. Our experience with IA-PA suggests that this extracorporeal anti-FVIII:C removal procedure is a valuable therapeutic tool for acquired haemophilia and can alleviate life-threatening haemorrhages.