Acute SR-GVHD occurs in approximately 15% of patients undergoing allogeneic hematopoietic stem cell transplant (HSCT), and is associated with a 70-90% long-term mortality rate. We previously reported that concomitant blockade of TNF-α and IL-2 pathways with infliximab combined with daclizumab have a synergistic therapeutic effect, with a high probability of complete resolution of SR-GVHD. Although various treatment modalities are effective in the treatment of SR-GVHD, minimal long-term follow up data exists for complete responders to second line treatments. Here we report long-term outcomes in a cohort of 23 subjects developing SR-GVHD treated with infliximab/daclizumab. A consecutive series of 141 patients with a variety of hematological and non-hematological malignancies as well as nonmalignant hematological disorders including severe aplastic anemia (SAA), paroxysmal nocturnal hemoglobinuria and pure red cells aplasia, underwent a reduced intensity allogeneic HSCT from an HLA identical or single antigen mismatched relative at a single institution between 2/2001 and 12/2008. Transplant conditioning consisted of cyclophosphamide (60 mg/kg days -7, -6) and fludarabine (25 mg/m2days -5 to -1) with or without equine ATG or 6-12 Gy of total body irradiation. GVHD prophylaxis was with cyclosporine with or without additional MMF or MTX. Twenty three patients (median age 35 years, range 13-65 years) developed SR-GVHD at a median of 28 days post transplant. SR-GVHD was defined as absence of response to at least 6 days of high dose methylprednisolone therapy. Following a diagnosis of SR-GVHD, patients received a combination of daclizumab (1mg/kg given on days 1, 4, 8, 15, 22), infliximab (10mg/kg given on days 1, 8, 15, 22), broad spectrum bacterial and anti-fungal prophylaxis, and had their methylprednisolone tapered to 1mg/kg/day. Combined cytokine blockade was highly active against SR-GVHD, with 21/23 (87.5%) patients achieving a complete response (CR), defined as total resolution of GVHD in all involved organ systems. All complete responders survived to hospital discharge. With a median follow-up of 9 years (range 5-10 years), 9/23 (39%) survive, including 6 patients without chronic GVHD whose immunosuppressive therapy (IST) has been discontinued and 3 patients with chronic GVHD (2 limited and 1 extensive) who continue to be tapered off IST. Fourteen of 21 patients with resolution of SR-GVHD died a median 173 days post transplant (range 67-1039 days), including 1 from complications related to recurrent SR-GVHD, 6 from progression of malignancy (all solid tumors), 2 from bleeding related to peptic ulcer disease and 5 from infectious complications including invasive fungal infection and CMV disease. A subgroup analysis showed 5/6 patients with SAA developing SR-GVHD had a complete response to combined infliximab/daclizimab. Remarkably, at a median 6 years follow up, 67% (4/6) of these SAA patients were long-term survivors. All these survivors have maintained normal blood counts and remained transfusion independent with 100% donor chimerism in myeloid and T-cell lineages.
Conclusion
Patients with SR-GVHD treated with infliximab combined with daclizumab had a high probability of achieving a complete response with nearly 40% of patients having long-term survival. This is the first report to show that long-term survival can be achieved in a substantial proportion of patients receiving combined IL-2 and TNF blockade for SR-GVHD.
Disclosures:
Off Label Use: Infliximab is FDA approved for the treatment of psoriasis, Crohn's disease, ankylosing spondylitis, psoriatic arthritis, rheumatoid arthritis and ulcerative colitis. Daclizumab gained FDA approval for use in transplant rejection.
Female Sex is Associated with Improved Long-Term Survival Following Allogeneic Hematopoietic Stem Cell Transplant
