Three-week versus four-week schedule of cisplatin and gemcitabine: results of a randomized phase II study.

BACKGROUND: The cisplatin and gemcitabine (GC) regimen is usually administered as a 4- or 3-week schedule; however, the best schedule to use is still unclear. We therefore started a randomized phase II trial to compare toxicity and dose intensity (DI) between these two GC schedules. PATIENTS AND METHODS: Ninety-six patients with non-small-cell lung cancer (NSCLC) and an additional 11 patients with an advanced epithelial neoplasm [bladder (n = 5), head and neck (n = 3), cervix (n = 1), esophageal (n = 1) or unknown primary carcinoma (n = 1)] were randomized to receive cisplatin 70 mg/m(2) intravenously on day 2 plus either gemcitabine 1000 mg/m(2) on days 1, 8 and 15 of a 28-day cycle or gemcitabine 1000 mg/m(2) on days 1 and 8 of a 21-day cycle. Planned DI (PDI) for the 4-week schedule was 750 mg/m(2)/week for gemcitabine and 17.5 mg/m(2)/week for cisplatin; for the 3-week regimen PDI was 666 mg/m(2)/week and 23 mg/m(2)/week for gemcitabine and cisplatin, respectively. RESULTS: From July 1998 to March 2000, 107 patients were randomized. Grade 3/4 neutropenia was observed in 27.8% of patients in the 3-week versus 22.5% in the 4-week arm (P = 0.69), while grade 3/4 thrombocytopenia was higher in the 4-week arm (29.5% versus 5.5% of patients; P = 0.14). A total of 398 cycles of therapy were delivered. Overall, 51% of cycles were modified in dose, timing or both in the 4-week arm, and 19% in the 3-week arm. The 21-day schedule of GC leads to a similar received DI of gemcitabine and higher cisplatin DI. Both regimens had activity in NSCLC, with a response rate of 39% (38% for the 4-week arm, and 42% for the 3-week arm). CONCLUSIONS: The 3-week schedule has similar DI to the 4-week schedule. However the 3-week regimen has a better compliance profile and a comparable response rate in NSCLC, supporting the use of such a schedule.