London, UK, 22 January 2007: BTG plc (LSE: BGC), the medical innovations company, today announces the successful outcome of a Phase I/II study of plevitrexed, a selective inhibitor of thymidylate synthase targeting gastric, pancreatic and ovarian cancer. The study, presented at the ASCO 2007 Gastrointestinal Cancers Symposium 1 in Orlando, Florida on 19 January, was designed to investigate the efficacy, safety and tolerability of plevitrexed in patients with advanced and/or metastatic gastric cancer.

Of the 28 patients who were evaluable for response at the recommended dose level of 130 mg/m 2 taken into the Phase II part of the study, five patients had a partial response (17.9% response rate) and a further 15 patients (53.6%) had stable disease giving an overall disease control rate of 71.4%. One patient on the lower dose of 65 mg/m 2 had a complete response and an additional five patients who received the higher dose of 165 mg/m 2 had stable disease.

The use of nutritional supplements improved the dosing consistency and allowed for greater dose intensity. Only 30.6% of patients required dose interruptions or modifications compared with 61.8% of patients in a previous plevitrexed study 2. The maximum tolerated dose doubled to 130 mg/m 2 and was given more consistently than in the previous study and with fewer missed doses, but no increase in grade 3/4 neutropenia was observed.