Excellent Long-Term Survival of Patients with Steroid-Refractory and Steroid-Dependent Acute Graft-Versus-Host Disease after Extracorporeal Photochemotherapy.

Despite posttransplantation immunosuppressive therapy, acute graft-versus-host disease (GVHD) remains a major cause of sickness and death. Second-line therapies for steroid-refractory acute GVHD have been used with limited success. Extracorporeal exposure of peripheral blood mononuclear cells to the photosensitizing agent 8-methoxypsoralen and UV-A radiation (ECP) has been shown to be effective in the treatment of selected diseases mediated by T cells. We have reviewed the responses and long-term outcome of 59 hematopoietic stem cell transplant (HSCT) patients treated from 1996 to 2003 with ECP for steroid-refractory acute GVHD, defined as progression or no improvement of acute GVHD after a minimum of 4 (range, 4–49, median 17) days of treatment with prednisone (n=37) or steroid-dependent acute GVHD, defined as flare-up of GVHD during prednisone taper (n=22). Patients received HSCT from 17 related and 42 unrelated donors. In 28 cases an HLA-mismatch between recipient and donor was present. Prior to ECP, grade III–IV GVHD was observed in 23 patients (39%) and grade II GVHD in 36 (61%). Organs involved included skin in 97% of patients, liver in 39%, and GI tract in 17%. Treatment consisted of ECP on two consecutive days per week (=1 cycle) for a median of 7 (range, 1–45) cycles administered within a median of 3 (range, 0.5–31) months in addition to cyclosporine A and prednisone. Three months after initiation of ECP complete resolution of GVHD was achieved in 82% of patients with cutaneous, 61% with liver, and 61% with gut involvement. Complete responses were obtained in 86% of patients with grade II, 55% of patients with grade III, and 30% of patients with grade IV acute GVHD. Probability of transplant-related mortality (TRM) at 4 years after HSCT is 15% in patients with complete response to ECP compared to 88% in patients not responding completely. After a median follow-up of 46 (range, 9–45) months since discontinuation of ECP, 28 (47%) patients are alive including 22 without chronic GVHD. Probability of survival (OS) at 4 years after HSCT is 59% in patients with complete response to ECP compared to 11% in patients not responding completely. Besides response to ECP only organ involvement and grade of GVHD at start of ECP, and ability to timely taper steroids during ECP had a significant impact on both TRM and OS. Thus, ECP is an effective adjunct therapy for acute steroid-refractory and steroid-dependent GVHD. Our long-term results demonstrate durability of responses without adverse events.