Irinotecan/Gemcitabine Shows Promising Survival Rate in Advanced Pancreatic Cancer Patients

The combination of irinotecan (CPT-11, Camptosar) andgemcitabine (Gemzar) produced a 1-year survival rate of 27%, which is greaterthan that reported for gemcitabine alone in previous studies in patients withadvanced pancreatic cancer (15% and 18% 1-year survival rates, respectively).These study results were published in a recent issue of the Journal of ClinicalOncology (20:1182-1191, 2002).

"The findings suggest that the addition of irinotecan to gemcitabine mayenhance the clinical benefit of gemcitabine as well as increase survival in adisease in which 8 out of 10 patients die within a year of beingdiagnosed," said Caio Max S. Rocha Lima, MD, assistant professor ofmedicine, University of South Florida, H. Lee Moffitt Cancer Center &Research Institute. "Irinotecan, the standard of care for the treatment ofadvanced colorectal cancer, is showing promise in this difficult tumor type andis offering hope to patients with this devastating disease."

Two previous phase II studies have demonstrated that irinotecan alone hasantitumor activity in pancreatic cancer. Gemcitabine is considered the standardof care for this disease. Studies have shown it demonstrates positive clinicaland tumor response rates and improves median and 1-year survival.

Multicenter Study

The current phase II, multicenter, open-label, single-arm study evaluated theefficacy and safety of irinotecan plus gemcitabine in 45 patients withpreviously untreated, unresectable, or metastatic pancreatic cancer. Mediansurvival in patients treated with the combination was 5.7 months (range:0.4-19.4+ months). Patients also experienced a favorable tumor response rate(tumor size decreased by ³ 50%) compared to the conventional rates reported forsingle-agent therapy. In addition, the combination was well tolerated, withminimal severe toxicity.

Study participants received repeated 21-day cycles of gemcitabine,1,000 mg/m² for 30 minutes, followed by irinotecan, 100 mg/m² for 90minutes, administered intravenously on days 1 and 8. The study’s end pointsincluded objective tumor response rate, time to tumor progression, and survival.

"The study findings are significant because patients with pancreaticcancer often are severely debilitated," said Dr. Rocha Lima. "We areencouraged by these data that show that the combination was safe, anddemonstrated notable 1-year survival. Based on these results, we have initiateda phase III study, which is now fully accrued and which will allow furtherevaluation of this combination therapy."