Patients ≥18 years with Eastern Cooperative Oncology Group performance status 0/1 and stage IIIB/IV NSCLC were included in this open-label, multicenter, dose-escalation phase I study. Treatment was administered in 3-week cycles: oral sunitinib 37.5 or 50 mg/day intermittently (Schedule 2/1: 2 weeks on treatment, 1 week off treatment) or 25 mg continuous daily dosing (CDD) schedule with intravenous infusions of gemcitabine (1000 or 1250 mg/m2 days 1, 8) and cisplatin (80 mg/m2 day 1).
A total of 28 evaluable patients were assigned to four dose levels. Most adverse events (AEs) on the Schedule 2/1 MTD were mild to moderate. Dose delays due to myelosuppression occurred on both schedules, limiting treatment to a median of four cycles. Four of 18 evaluable patients (22 % ) on Schedule 2/1 and 1 of 6 patients (17 % ) on the CDD schedule had confirmed partial responses.
The MTD was identified as sunitinib 37.5 mg (Schedule 2/1), gemcitabine 1250 mg/m2, and cisplatin 80 mg/m2, with most AEs being mild to moderate. However, frequent dose delays due to myelosuppression occurred. There was evidence of antitumor activity with this combination.