VION ANNOUNCES INITIAL RESULTS FROM LUNG CANCER STUDY

Vion Pharmaceuticals has presented data on its lead anticancer agent, Cloretazine (VNP40101M), as a single agent in a Phase II trial in patients with relapsed or refractory small-cell lung cancer.

The Phase II trial is evaluating Cloretazine in two separate subpopulations of small-cell lung cancer: sensitive relapsed disease and refractory disease. Sensitive relapsed disease is defined as relapse after three months of first-line therapy, and refractory disease is defined as relapse within three months of first-line therapy. Data presented are from total of 36 evaluable patients: 19 patients in the sensitive relapsed arm and 17 patients in the refractory arm.

Patients in the trial initially received 125 mg/m2 of Cloretazine weekly for three weeks every six weeks. This dose was later reduced by protocol amendment to 100 mg/m2 weekly for three weeks every six weeks due to significant thrombocytopenia at the initial dose level.

Grade 3 and 4 thrombocytopenia has been the most serious toxicity observed, and has delayed additional treatment in several patients. Early results suggest that the reduced dose of Cloretazine causes less thrombocytopenia (no grade 3 or 4 thromobocytopenia in the first four patients at this dose) but maintains disease activity.

Both arms of the trial met the criteria for advancement to the second stage and continue to enroll patients. If both arms complete full accrual, there will be a total of 50 patients on the sensitive relapsed arm and 37 patients on the refractory arm.