Efficacy and safety of continuous daily sunitinib dosing in previously treated advanced non-small cell lung cancer (NSCLC): Results from a phase II study

Abstract

7542 Background: Sunitinib malate (SU), an oral, multitargeted tyrosine kinase inhibitor of VEGFRs, PDGFRs, KIT, RET, and FLT3, has demonstrated activity in recurrent advanced NSCLC on the 4/2 schedule (4 weeks [wks] on treatment followed by 2 wks off), with a partial response (PR) rate of 11% (Socinski, ESMO 2006). A continuous dosing (CD) schedule of SU was additionally evaluated for safety and efficacy in this multicenter phase II study. Methods: Eligible patients (pts) had stage IIIB/IV NSCLC previously treated with 1–2 chemotherapy regimens, ECOG PS =1, and adequate organ function. Pts with brain metastases or recent gross hemoptysis were excluded. Pts received oral SU 37.5 mg/day continuously in 4-wk cycles. The primary endpoint was objective response rate per RECIST. Secondary endpoints included progression-free survival (PFS), overall survival, and safety. Results: Forty-seven pts were treated on the CD schedule: median age 60 yrs (range 37–81); male 57%; ECOG PS 0/1/2 49%/49%/2%; adenocarcinoma 53%, squamous cell carcinoma 15%, other 32%; median number of SU cycles initiated: 3 (range 1–10). One pt (2%) had a confirmed PR and 8 pts (17%) had stable disease >3 months. Median PFS was 12.1 wks (95% CI: 8.6–13.7). SU was generally well tolerated; most adverse events (AEs) were grade 1/2 and included fatigue/asthenia, pain/myalgia, nausea/vomiting, diarrhea, dyspnea, and stomatitis/mucosal inflammation. Grade =3 AEs included fatigue/asthenia (15%), hypertension (6%), hypoxia (6%), dyspnea (4%), and hemoptysis (2%). Treatment-related serious AEs included congestive heart failure (CHF; 1 pt), gastrointestinal bleeding (1 pt), hypomagnesemia (1 pt), and hypoxic respiratory failure (1 pt). One pt died due to possible treatment-related CHF. Conclusions: SU on a CD schedule is associated with an acceptable safety profile when administered to previously treated NSCLC pts, and there is documented preliminary evidence of activity, with 1 PR and a median PFS of 12.1 wks. These data support further study of continuous dosing of SU in combination with other treatments for NSCLC. No significant financial relationships to disclose.