Evaluation of the re-introducing FOLFOX or XELOX ± bevacizumab in relapsed colorectal cancer patients treated with oxaliplatin as adjuvant chemotherapy (REACT study).

Abstract

634 Background: Chemotherapy in relapsed colon cancer patients (pts) treated with oxaliplatin as adjuvant chemotherapy is under debate. REACT study aimed to investigate the efficacy of re-introducing FOLFOX or XELOX ± bevacizumab therapy for recurrent colorectal cancer pts after adjuvant chemotherapy including oxaliplatin. Methods: Pts with past history of adjuvant chemotherapy including oxaliplatin (FOLFOX, XELOX or SOX) with a cumulative dose of more than 400 mg/m2, and recurrence observed by imaging after more than 6 months post adjuvant chemotherapy participated in this trial. Primary endpoints were response rate (RR) and disease control rate (DCR). Key secondary endpoints were progression-free survival (PFS), time to treatment failure (TTF), overall survival (OS) and safety. Results: A total of 31 pts were enrolled between Oct 2012 and Oct 2016. Of 29 eligible pts, 7 received FOLFOX ± bevacizumab, and 22 received XELOX ± bevacizumab. 28 of the pts received bevacizumab. The RR was 66.7% (95% CI, 46.0-83.5) and the DCR was 88.9% (95% CI, 70.8-97.6). The RR for oxaliplatin free-interval was 100.0% (n = 4, 95% CI, 39.8-100.0) in 6 to 12 months, 60.9% (n = 25, 95% CI, 38.5-80.3%) over 12 month, respectively. Median PFS, TTF and OS were 10.9 months (95% CI, 7.0-19.0), 6.3 months (95% CI, 2.8-8.0) and 29.1 months (95% CI, 20.3-53.3). The most common grade 3 or 4 adverse event was hypertension (19.4%). Grade 3 or worse peripheral sensory neuropathy developed only two pts (6.5%). Allergic reactions occurred in 12.9% of the pts, with one (3.2%) grade 3 episode. There were no other severe treatment-related adverse events. Conclusions: Re-introduction of oxaliplatin was feasible and achieved high RR or DCR in after more than 6 months post adjuvant chemotherapy including oxaliplatin. Clinical trial information: UMIN000006523.