Cell Genesys reports positive results from Phase I bladder cancer trial

The Phase I, open label, dose-escalation trial was designed to evaluate intravesical (into the bladder) administration of CG0070 in patients with superficial bladder cancer who had failed previous therapy with BCG. The trial, which has enrolled a total of 35 patients, was designed to first evaluate escalating single-dose levels of CG0070 and was then expanded to evaluate escalating multiple dose regimens administered once weekly or once every four weeks. The primary endpoints of the study were safety and the determination of a maximum tolerated dose.

Twenty-two patients have been enrolled into the dose expansion cohort of the trial. Sixteen patients enrolled into the two lowest of three dose groups have completed dosing of CG0070 administered once weekly or once every four weeks. Ten of these 16 patients showed anti-tumor activity as measured by complete response at follow-up cystoscopy.

An additional six patients have been enrolled at the third dose level at both dosing schedules and are currently being dosed. Evidence of anti-tumor activity documented by a complete response at follow-up cystoscopy performed at approximately three months following administration of CG0070 was observed in the two lowest dose cohorts at both dosing schedules. Five of six patients who received CG0070 administered once weekly, three of whom were in the first (lowest) dose cohort, experienced a complete response, and five of 10 patients who received CG0070 once every four weeks, of whom three were in the first dose cohort, experienced a complete response.

Patients treated at the first dose level all had incompletely resected tumor remaining in their bladder at the time of initial dosing. The longest response durations measured for the weekly and every four-week schedules were continuing at 10.4 months and 7.5 months, respectively. Multi-dose administration of intravesical CG0070 has a generally tolerable safety profile with predominantly local toxicities.