NEW HAVEN, Conn., June 2 /PRNewswire-FirstCall/ -- VION PHARMACEUTICALS,INC. (Nasdaq: VION) today announced that interim data from the pivotal PhaseII trial of its lead anticancer agent Cloretazine(R) (VNP40101M) in elderlypatients with de novo poor-risk acute myelogenous leukemia (AML) had beenpresented at the 44th Annual Meeting of the American Society of ClinicalOncology (ASCO(R)) in Chicago, Illinois.

At ASCO(R), data were presented in 85 evaluable patients. The median ageof these patients was 73 years (range of 60-87 years). Ninety-five percent ofpatients had two or more risk factors associated with a poor prognosis inelderly AML and 74% had three or more risk factors. The most common riskfactors were age greater than or equal to 70 (78% of patients), and cardiacand pulmonary dysfunction (73% and 76% of patients respectively). Inaddition, 47% of patients had unfavorable cytogenetics.

The overall complete response rate was 35% (22 CR and 8 CRp). 90% ofresponses occurred after first induction treatment. While follow-up is stillongoing, the median (range) of overall survival for responders was 6.3 months(1.7-16.4 months) and for all patients was 3.2 months (0.1-16.4 months).

The induction death rate within 30 days of first induction treatment was14%. The majority of first induction deaths were either due to progression ofdisease or infection. Myelosuppression was the primary toxicity, withpneumonia, infection and sepsis and non-infectious pulmonary disorders(hypoxia and dyspnea) being the most common severe adverse events (greaterthan or equal to grade 3).

Dr. Gary Schiller, Professor of Medicine at the David Geffen School ofMedicine at UCLA and a lead investigator on the study, said 'The responsesobserved in this trial represent a clinically meaningful outcome for many ofthese difficult-to-treat AML patients. As a single-agent, single-infusiontherapy, Cloretazine(R) (VNP40101M) has the potential to be an important newtreatment option for older patients with poor-risk AML.'