Ipilimumab (MDX-010) Safety and Clinical Response Data in Lymphomas and Leukemia Presented at the 48th American Society of Hematology Annual Meeting
Monday December 11, 4:12 pm ET
PRINCETON, N.J., Dec. 11 /PRNewswire-FirstCall/ -- Medarex, Inc. (Nasdaq: MEDX - News) today announced safety and response data in patients treated with ipilimumab (also known as MDX-010) for lymphomas and leukemia from two separate Phase I and Phase I/II clinical trials. These data were presented during the 48th American Society of Hematology (ASH) Annual Meeting and Exposition, December 9-12, 2006, in Orlando, FL.
Oral Presentation Reports Clinical Responses from Ipilimumab Phase I Trial in Patients Failing Bone Marrow Transplant (Abstract #410)
In a single dose, dose-escalation Phase I trial of ipilimumab, complete or partial responses were observed in two of 17 patients who were treated with ipilimumab after relapse of their tumor following allogeneic hematopoietic stem cell transplantation. One patient with Hodgkin's lymphoma experienced a complete response that is ongoing at over two months duration, and one patient with mantle cell Non-Hodgkin's lymphoma experienced a partial response of three months duration. Additional anti-tumor responses were experienced by two patients with leukemia, one in which circulating leukemic cells were reduced, and another who maintained molecular remission of chronic myeloid leukemia after stopping standard therapy (imatinib).
In the Phase I clinical trial, 17 patients with lymphomas (Hodgkin's, Non- Hodgkin's), myeloma, leukemia (chronic myeloid, chronic lymphocytic, acute myeloid), renal and breast cancers received a single dose of ipilimumab ranging from 0.1 mg/kg to 3.0 mg/kg. The data showed that the treatment was generally tolerable and without dose-limiting toxicities or clinically important graft-versus-host disease, an immune complication that may increase following transplantation. Two possible immune-related adverse events included one Grade II thyroid function test abnormalities (without clinical symptoms) and one Grade III polyarthropathy in a patient with acute myeloid leukemia following donor lymphocytic infusion, a treatment that can also cause this adverse event and which resolved with corticosteroids. Further studies with higher doses of ipilimumab are planned.
Poster Presentation Shows Response Data from Ipilimumab Phase I/II Trial in Patients with Relapsed or Refractory Follicular Lymphoma (Abstract #2729)
In an initial group of 12 patients with relapsed or refractory follicular lymphoma in an ongoing Phase I/II clinical trial, one patient of six who had been previously treated with a lymphoma vaccine experienced a partial response of multiple abdominal nodules that is ongoing at over ten months duration.
In the Phase I/II clinical trial, patients with relapsed or refractory follicular lymphoma received an initial dose of 3.0 mg/kg of ipilimumab, followed by 1.0 mg/kg of ipilimumab given monthly for up to three doses, with plans to escalate to 3.0 mg/kg of ipilimumab given monthly for up to four doses. Enrollment is stratified into two cohorts, with half of the patients required to be previously treated with a lymphoma vaccine. Results of this trial to date show that ipilimumab was generally tolerable. Six instances of Grade III adverse events were reported in the clinical trial, including diarrhea (four), fatigue (one) and neutropenia (one), all similar to adverse events previously reported with anti-CTLA-4 antibody therapy and consistent with the immune-based mechanism of action of ipilimumab. The second group of patients to be treated with 3.0 mg/kg of ipilimumab given monthly for four doses is currently enrolling patients.
"The encouraging data presented at the ASH meeting continue to support our belief that ipilimumab may represent a potentially new therapeutic with broad application in solid and liquid tumors," said Irwin Lerner, Chairman of the Board of Directors and Interim President and CEO of Medarex. |
