Bevacizumab (Bv) single-agent maintenance following Bv-based chemotherapy in patients with advanced non-small cell lung cancer (NSCLC): Results from an exploratory analysis of the AVAiL study

Abstract

e19001 Background: The significant survival benefits observed with Bv plus chemotherapy in pivotal NSCLC trials were generated using treatment to progression. Given that little data on the use of single-agent Bv as maintenance therapy are currently available, we report here the results of an analysis focused on the maintenance phase of the AVAiL study. Methods: AVAiL, a randomized, international, placebo-controlled phase III trial, evaluated Bv plus cisplatin-gemcitabine (CG) in pts with previously untreated advanced, non-squamous NSCLC, with performance status 0/1. 1,043 pts (age 20–83) were randomized to C 80mg/m2 and G 1,250mg/m2 q3w for up to 6 cycles plus either Bv 7.5mg/kg q3w (Bv 7.5; n=345), Bv 15mg/kg q3w (Bv 15; n=351) or placebo (Pl; n=347). Bv/Pl was administered until disease progression. This retrospective analysis focused on progression-free survival (PFS) and overall survival (OS) of the 376 patients who received blinded Bv (n=174 and n=162 for Bv 7.5 and 15) or Pl monotherapy (n=41) after completing 6 cycles of CG + Bv or CG + Pl (as specified in the protocol; most patients received 6 cycles). PFS was measured from last day of last cycle of CG + Bv/Pl to disease progression or death. Results: In the overall population, Bv reduced the risk of progression or death by 25% vs Pl (PFS primary endpoint (HR=0.75 [0.64–0.87] and 0.85 [0.73–1] for Bv 7.5 and Bv 15, respectively). When analyzing the outcome of the post chemotherapy maintenance phase, the use of Bv as single agent yielded median PFS of 3.2 months (95%CI [3–5]) for Pl, 4.6 months (95%CI [4–6]) for Bv 7.5 and 4.6 months (95%CI [4–5]) for Bv 15.The OS results for this maintenance analysis are consistent with those from the overall population in which the PFS findings were not associated with an OS benefit. Conclusions: This post-hoc analysis, focused on the maintenance phase of AVAiL, suggests that Bv used as single-agent maintenance therapy appears to confer clinical benefit beyond the chemotherapy phase. This finding warrants further exploration in future studies. [Table: see text]