Oregovomab Produced Favorable Clinical Trial Results.

2001 NOV 14 - (NewsRx.com & NewsRx.net) -- AltaRex Corp. (ALXFF) announced favorable early results from a concurrent OvaRex/second-line chemotherapy clinical trial in relapsed ovarian cancer where prognosis is extraordinarily poor, and where salvage chemotherapy alone provides limited clinical benefit. The announcement was made at both the UBS Warburg and BioContact biotechnology conferences.

For patients at this stage of disease, salvage chemotherapy typically has a response rate of only 15-25% with a survival benefit of approximately one year. Dr. Alan Gordon of U.S. Oncology in Houston, Texas, is the lead investigator of the 20-patient, fully enrolled, Phase II open-label OvaRex (oregovomab) study.

A primary objective of the OvaRex trial is to induce a robust tumor-specific immune response, including chemotherapy-insensitive memory T and B cells, in the 12 weeks prior to beginning second-line chemotherapy. Patients had the option to continue on OvaRex while also receiving chemotherapy. It has been postulated in the oncology community that administration of immunotherapy with chemotherapy can be problematic because chemotherapy could actually suppress the immune response.

In this trial, both robust humoral (71% of patients evaluated) and cellular (63% of patients evaluated) immune responses, including T helper cells and killer T cells (CTLs) that target both the tumor associated antigen CA 125 and the patient's own tumor, were induced following administration of OvaRex monoclonal antibody (MAb). Further, immune responses were maintained, not compromised, in those patients receiving chemotherapy, suggesting the possible additive benefit of OvaRex treatment combined with salvage chemotherapy.

Fifteen of the 20 patients are still alive with median estimated survival not yet calculable. The newly reported data ...