We reviewed the medical records of 18 consecutive adult allo-SCT patients who received etanercept (Enbrel, Pfizer, Seoul, Korea) to treat steroid-refractory acute GVHD. The clinical outcomes, including acute GVHD and underlying diseases, responsiveness to etanercept, overall survival after transplantation, and clinical parameters related to the administration of etanercept were reviewed retrospectively.

The allo-SCT was performed between June 2007 and March 2009 at Ajou University Hospital. The patients' characteristics are described in Table 1. As preparative regimens, two patients with severe aplastic anemia (SAA) were given cyclophosphamide (Cy) and thymoglobulin and five patients with acute leukemia or myelodysplastic syndrome (MDS) were given busulfan-cyclophosphamide (BuCy). Reduced intensity stem cell transplantation (RIST; busulfan + fludarabine + thymoglobulin) was used in eight patients, including one patient with comorbid disease and seven patients as salvage therapy after failure of a first transplantation (one patient with prior allo-SCT and the others with prior auto-SCT). Thymoglobulin was administered for RIST and for conditioning aplastic anemia.

The GVHD prophylaxis consisted of cyclosporin A (CsA; 3 mg/kg/day intravenously; Sandimun, Norvatis, Seoul, Korea) and a short course of methotrexate (MTX; 15 mg/m² on D+1 and 10 mg/m² on D+3, D+6, and D+11) in all cases; the MTX was omitted on D+11 in the RIST setting. If no GVHD developed, the CsA was to be tapered off by day 100. The first-line therapy for acute GVHD was a combination of CsA + steroid or FK506 + steroid at a dose equivalent to 2 mg/kg/day of methylprednisolone in nine and seven patients, respectively. The physicians changed the oral CsA to intravenous FK506 injection in the seven patients who could not take CsA easily on schedule. One myeloma patient who tapered off CsA rapidly after transplantation because of sustained M-protein was treated with steroid alone for his acute GVHD. The assessment and grading of acute GVHD was based on the clinical findings and followed previous reports [9,10,11].

Steroid refractoriness was defined as a progression of acute GVHD or no improvement in acute GVHD after at least 7 days of immunosuppressive therapy, including 2 mg/kg/day of methylprednisolone. Steroid-dependent patients were excluded from the analysis. The patients were given 25 mg of etanercept subcutaneously twice weekly for 4 weeks. The response was evaluated 4 weeks after starting the etanercept and the overall response was calculated as the sum of the organ-specific acute GVHD.

A CR was defined as the complete resolution of all manifestations of acute GVHD in all evaluable organs within 4 weeks of initiating the etanercept. A partial response (PR) was defined as a decrease in the severity of GVHD by at least 1 overall grade without deterioration of any organ system. New involvement of acute GVHD in any organ was considered progressive disease [8].

All patients were given prophylaxis with oral quinolone, itraconazole, and acyclovir starting with conditioning therapy until D+28. The daily administration of antituberculosis (rifampin and isoniazid) and an antiprotozoal drug (trimethoprim-sulfamethoxazole) was stopped immediately after the stem cell infusion and was changed to twice weekly after engraftment. Next, granulocyte-colony stimulating factor (G-CSF; Grasin, Kyowa Hakko Kirin, Tokyo, Japan) was given at a dose of 10 mg/kg/day subcutaneously to help the patients recover from neutropenia (absolute neutrophil count < 500/mm³). No antibiotics or antifungals were administrated for prophylaxis during or after etanercept therapy.

The GVHD grades before and after etanercept treatment were compared using the nonparametric Wilcoxon signed-rank test. The relationships between the clinical parameters and the response to etanercept were analyzed using logistic regression. All statistical analyses were conducted using SPSS version 13.0 (SPSS Inc., Chicago, IL, USA).

The median patient age was 43.5 years (range, 20 to 63), with males comprising 72.2% of the population. The transplantation data are shown in Table 1. There were seven patients with AML, four with multiple myeloma, three with SAA, two with acute lymphoblastic leukemia (ALL), and one patient each with MDS and chronic idiopathic myelofibrosis. The median interval from diagnosis to allo-SCT was 238.5 days. Fourteen patients received peripheral blood stem cells as a source of hematopoietic stem cells and unrelated transplantation was performed in nine patients. Transplantation from a female donor to a male patient occurred in eight cases. The initial treatment of acute GVHD was prednisone + FK506 in nine patients, prednisone + CsA in seven patients, and prednisone alone for one patient. The median days to starting etanercept from the documentation of steroid-refractoriness was 24 days and the median dose of etanercept was 100 mg (range, 25 to 200).

Eighteen patients who received etanercept to treat grade II to IV acute GVHD were enrolled in the analysis and were evaluable for response. Nine of the patients responded to etanercept (50% response rate). Thirteen patients had grade III or IV acute GVHD with a 38.5% response rate (5/13). Ten patients received four to eight of the planned eight doses (median four doses) of etanercept. Using a nonparametric test to compare before and after treatment, etanercept had a downgrading effect on acute GVHD (p = 0.022). The incidence of higher grade skin and gut GVHD decreased significantly after administering etanercept (p = 0.001 and p = 0.011, respectively), while the incidence of liver GVHD did not change. In terms of the overall grade of acute GVHD, no patient had a CR, while a PR occurred in 80% of the grade II patients and 57% of the grade IV patients. Only 17% of the patients with grade III acute GVHD responded to etanercept therapy (Table 2). One patient who received tandem allo-SCT died of acute GVHD and two of six patients with auto-allo-SCT are alive with improved acute GVHD grades and resulting limited chronic GVHD. The steroid dose could be reduced by more than 50% in eight of the nine patients who showed a clinical response.

Fifteen infections occurred in 12 patients. The lungs were the most common site of infection (8 of 15) and one case each of esophagitis, meningitis, and intra-abdominal abscess was documented. Candidemia was observed in two patients. Two patients developed cytomegalovirus reactivation that required pre-emptive ganciclovir treatment. Six patients experienced bleeding episodes, which were controlled without surgical intervention, except for one patient who died of an intracranial hemorrhage. The gastrointestinal tract was the most frequent site of bleeding.

Five of 18 patients are currently alive, with a median follow-up of 737.5 days (range, 497 to 1,139) after transplantation. Patients not responding to etanercept treatment had 100% mortality with a median survival of 92 days (range, 45 to 462) after transplantation, whereas the responders had a 55.6% survival rate. Five patients died of worsening acute GVHD, three patients died of a relapse of their underlying diseases (AML, n = 2; ALL, n = 1), and four patients died of pulmonary infection, including one patient who also had pulmonary aspergillosis. One patient died of an intracranial hemorrhage. In summary, five patients died of GVHD and three of them showed no response, resulting in the worsening of acute GVHD. Another two of five patients responded to etanercept initially, but eventually experienced a flared acute GVHD and subsequently died of extensive chronic GVHD.

No clinical parameter affected the response rate of etanercept, including patient characteristics, transplantation kinetics, acute GVHD outcomes, and various data related to etanercept. Disease status at transplantation did not affect the response rate to etanercept in the seven patients with AML. The statistical significance of disease status as a clinical parameter could not be analyzed in the patients with ALL, SAA, MDS, and myelofibrosis because of the extremely small sample sizes of the subgroups.