Broad potential for gastric cancer drug

Antisoma, the biopharmaceutical company specialising in the development of anti-cancer drugs, has presented positive final results from its pilot phase II study of R1549 in gastric cancer.

The trial, which has been funded since November 2002 by Antisoma's co-development partner, Roche, evaluated the drug in a small group of patients who had received surgery to treat advanced gastric cancer. Eight patients who received surgery plus R1549 were compared with seven patients who received surgery alone. Tolerability findings were comparable to those observed in patients receiving R1549 for ovarian cancer. As expected, based on the small size of the trial, no statistically significant differences were observed in survival time between the treated and untreated patients.

The importance of these results lies in the extension of favourable tolerability data to a broader patient population than ovarian cancer sufferers. The gastric study included patients with a different type of tumour, a different surgical history and for the first time men as well as women. This study makes possible the future evaluation of R1549 in gastric and other abdominal cancers in the event of positive results from the drug's pivotal phase III study in ovarian cancer. Antisoma and Roche expect to announce the principal results of the ovarian study during the first half of 2004. A previous phase II study in ovarian cancer showed a statistically significant increase in survival time, with enhanced five- and ten-year survival.

An investigator in the study, Dr Bruce Sizer of Essex County Hospital, Colchester, UK, said: 'This trial was a useful first step in evaluating R1549 in gastric cancer. Further trials will be needed to fully elucidate the value of the drug in this and other possible abdominal cancer indications.'

Glyn Edwards, CEO of Antisoma, said: 'This is an exciting time for Antisoma as we await the results of our pivotal study of R1549 in ovarian cancer. By showing that R1549 can also be given safely to patients with gastric cancer, today's results provide a potential springboard for the extension of the development programme to a range of abdominal cancers.'

Gastric cancer

Approximately 875,000 new cases of gastric cancer are diagnosed worldwide each year. Treatment options are limited and survival rates remain poor, as approximately 80% of patients present with locally advanced or metastatic disease. The World Health Organisation estimates that gastric cancer killed almost 650,000 people worldwide in 2000.