Acute graft-versus-host disease (aGVHD) is a serious complication of allogeneic peripheral blood stem cell transplantation (PBSCT). Patients with severe aGVHD not responding to treatment with steroids have a poor prognosis. We treated three patients with severe aGVHD refractory to steroids with infliximab. Patients (MDS 1, NHL 1, ALL 1) developed grade II-IV GVHD at a median of 13 days (range 9-17) after non-myeloablative PBSCT (HLA mismatched). All patients had received treatment with high-dose steroids for a median of 7 days (range 7-10) in addition to mycophenolate mofetil (MMF) (one). Infliximab was given in 3 weekly doses of 5 mg/kg. In one of three patients a partial resolution of diarrhea and minor improvement of skin were observed. One patient died with refractory GVHD. Infliximab is apparently an effective drug for the treatment of aGVHD, but can be more effective at doses of 5 mg/kg or higher and/or by administering it repeatedly every week.