Evaluation of a CDS-Specific Immunotoxin for Treatment of Acute Graft- Versus-Host Disease After Allogeneic Marrow Transplantation

Acute graft-versus-host disease (GVHD) is most often treated with high dose glucocorticoids, but less than half of patients have durable overall improvement. Previous phase I and phase I1 studies suggested that treatment with a CD5specific immunotoxin (XomaZyme-CD5 Plus) could ameliorate symptoms of GVHD. In a randomized, double-blind trial, we compared XomaZyme-CD5 Plus and glucocorticoids versus placebo and glucocorticoids as initial therapy for 243 patients who developed acute GVHD after allogeneic marrow transplantation. The study drug (XomaZyme CD5-Plus or an identical appearing placebo) was administered at a dose of 0.1 mglkg body weight on each of 14 consecutive days. All patients were treated concomitantly with a standard regimen of methylprednisolone. At the time of entry on study, 94% of patients had a rash, 56% had hyperbilirubinemia, 61% had diarrhea, and 84% had nausea and vomiting. At 3,4, and 5 weeks after starting treatment, symptom severity was less in the CD5 group than in the placebo group.