Prophylactic G-CSF and antibiotics enable a significant dose-escalation of triplet-chemotherapy in non-small cell lung cancer

In advanced non-small cell lung cancer (NSCLC) the clinical benefit of a platinum-based doublet is only modest, therefore, attenuated dosed three-drug combinations are investigated. We hypothesized that with adequate support a full dosed chemotherapy triplet is feasible. The study was designed as a dose finding study of paclitaxel in chemotherapy-naive patients. Paclitaxel was given as a 3-h infusion on day 1, followed by fixed doses of teniposide (or etoposide) 100 mg/m² days 1, 3, 5 and cisplatin 80 mg/m² day 1 every 3 weeks. As myelotoxicity was expected to be the dose-limiting toxicity, prophylactic G-CSF and antibiotic support was evaluated. Indeed, paclitaxel 120 mg/m² resulted in dose-limiting neutropenia, despite G-CSF support. Teniposide/etoposide day 1, 3, 5 was less myelotoxic compared to day 1, 2, 3. G-CSF support allowed paclitaxel dose-escalation to 250 mg/m². The addition of prophylactic antibiotics enabled dose-escalation to 275 mg/m² without reaching MTD. In conclusion, G-CSF and antibiotics prophylaxis enables the delivery of a full dosed chemotherapy triplet in previously untreated NSCLC patients.