ABSTRACT
Gemcitabine (G) and cisplatin (P) are active reference agents in patients with non-small-cell lung cancer (NSCLC). Ifosfamide (I) has also been approved for NSCLC treatment. This phase I trial aimed to determine the dose-limiting toxicity (DLT), maximum tolerated dose [maximum tolerated dosage (MTD)], and recommended dose (RD) of a GIP combination in patients with advanced/metastatic NSCLC. In this study, one cycle of chemotherapy combined the following: ifosfamide: 3 g/m2 fixed dose (24-hour intravenous infusion) combined with mesna, day 1; gemcitabine: starting dose 1,000 mg/m2/d, escalating by 250 mg/m2 increments, days 1 and 15; cisplatin: starting dose 80 mg/m2, subsequently 100 mg/m2, day 15; in cohorts of at least 3 patients. Cycles were repeated every 28 days and no hematopoietic growth factors were administered. DLT was evaluated after the first chemotherapy cycle. Thirty-three patients (30 men, 3 women) with stage III (14 patients)/IV (19 patients) NSCLC were treated at eight dose levels, receiving 109 cycles of chemotherapy. Neutropenia was the only DLT reported. Although the MTD was not reached at the highest tested dose level, the RD chosen corresponds to the full doses of the GP3000 doublet standard (G: 3,000 mg/m2; P: 100 mg/m2 per cycle) every 28 days. Nonhematologic toxicities were mainly grade I-II. Relative dose intensities of G, I, and P at the RD were 96%, 98%, and 96%, respectively. Sixteen of 33 patients with measurable/evaluable disease had an objective response including two complete responses. In conclusion, GIP chemotherapy is safe and appears to be active in patients with NSCLC. The RD is gemcitabine: 1,500 mg/m2 days 1 and 15; ifosfamide: 3 g/m2 day 1; cisplatin: 100 mg/m2 day 15. A confirmatory phase II study is currently under way, before a phase III trial of GIP versus GP.
