Randomized phase II study of CPT-11 versus PTX versus each combination chemotherapy with S-1 for advanced gastric cancer that is refractory to S-1 or S-1 plus CDDP: OGSG0701.

BACKGROUND

To compare irinotecan-alone, paclitaxel-alone, and each combination chemotherapy with S-1 in patients with advanced gastric cancer (AGC) that is refractory to S-1 or S-1 plus cisplatin (SP).

METHODS

Patients with AGC after first-line chemotherapy with S-1 or SP, or patients during adjuvant chemotherapy or within 26 weeks after adjuvant chemotherapy completion with S-1 with confirmed disease progression were eligible. Patients were randomly divided into four groups based on treatment: irinotecan-alone (irinotecan; 150 mg/m, day 1, q14 days), paclitaxel-alone (paclitaxel; 80 mg/m, days 1, 8, 15, q28 days), S-1 plus irinotecan (irinotecan; 80 mg/m, days 1, 15, S-1; 80 mg/m, days 1-21, q35 days), and S-1 plus paclitaxel (paclitaxel; 50 mg/m, day1, 8, S-1; 80 mg/m, days 1-14, q21 days). The primary endpoint was overall survival (OS) and secondary endpoints were progression-free survival (PFS), response rate, and safety.

RESULTS

From July 2008 to March 2012, 127 patients were enrolled. No difference in median OS was observed in the irinotecan vs. paclitaxel groups or in the monotherapy groups vs. the S-1 combination therapy groups. Median PFS was longer in the paclitaxel group compared with the irinotecan group (4.1 vs. 3.6 months, p = 0.035), although no difference was observed when comparing monotherapy vs. S-1 combination. The most common grade 3 to 4 hematological adverse events were neutropenia with no difference in incidence rate across the treatment groups.

CONCLUSIONS

There was no difference in OS between irinotecan and paclitaxel no in OS prolongation of S-1 combination therapy in second-line chemotherapy.