Phase 2 study of S-1 and carboplatin plus bevacizumab followed by maintenance S-1 and bevacizumab for chemotherapy-naive patients with advanced nonsquamous non-small cell lung cancer.

Background: A previous phase 3 trial demonstrated noninferiority in terms of overall survival for combined S-1 (an oral fluoropyrimidine) and carboplatin compared with combined paclitaxel and carboplatin as first-line treatment for advanced non-small cell lung cancer (NSCLC). In the current study, the authors evaluated the efficacy and safety of combined S-1, carboplatin, and bevacizumab followed by maintenance with S-1 and bevacizumab in chemotherapy-naive patients with advanced nonsquamous NSCLC.

Methods: Patients received carboplatin (area under the concentration-time curve, 5 mg mL(-1) per minute) and bevacizumab (15 mg/kg) on day 1 plus oral S-1 (80 mg/m2 per day) on days 1 through 14 every 21 days for up to 6 cycles. For patients without disease progression, S-1 and bevacizumab were continued until disease progression or unacceptable toxicity developed.

Results: Forty-eight patients were enrolled in the phase 2 study; of these, 35 patients (72.9%) completed at least 4 cycles. Most toxicities of grade ≥3 were hematologic, and no increase in relative incidence associated with maintenance with S-1 and bevacizumab was observed. The objective response rate was 54.2% (95% confidence interval, 39.2%-68.6%), and the median progression-free survival was 6.8 months (95% confidence interval, 4.3-8.2 months).

Conclusions: The regimen of combined S-1, carboplatin, and bevacizumab followed by maintenance with S-1 and bevacizumab was active and feasible as first-line treatment for advanced nonsquamous NSCLC.