Evaluation of FOLFOX or CAPOX reintroduction with or without bevacizumab in relapsed colorectal cancer patients treated with oxaliplatin as adjuvant chemotherapy (REACT study)

Background Chemotherapy in relapsed colorectal cancer patients treated with oxaliplatin as adjuvant chemotherapy is under debate. REACT study aimed to investigate the efficacy of reintroducing modified FOLFOX6 (mFOLFOX6) or CAPOX with or without bevacizumab in recurrent colorectal cancer patients after oxaliplatin adjuvant chemotherapy. Methods Patients that participated in this trial had a medical history of adjuvant chemotherapy, including oxaliplatin with a cumulative dose greater than 400 mg/m(2), and recurrence that was diagnosed more six months post adjuvant chemotherapy. Primary endpoints were response rate (RR) and disease control rate (DCR), while key secondary endpoints were time to treatment failure (TTF), progression-free survival (PFS), overall survival (OS), and safety. Results A total of 31 patients were enrolled between October 2012 and October 2016. Of the 29 eligible patients, 7 received mFOLFOX6 and 22 received CAPOX. The RR was 62.1% (95% confidence interval 42.3-79.3) and the DCR was 82.8% (95% confidence interval 64.2-94.2). The RR for oxaliplatin-free interval was 100.0% in months 6-12 and 56.0% after 12 months. Median TTF, PFS, and OS were 6.3, 10.8, and 28.7 months, respectively. Grade 3 or worse peripheral sensory neuropathy developed in 6.5%. Allergic reactions occurred in 12.9% of the patients, with one (3.2%) grade 3 episode. There were no other severe treatment-related adverse events. Conclusion Reintroduction of oxaliplatin was feasible and achieved high RR or DCR in patients after more than 6 months post oxaliplatin adjuvant chemotherapy.