PURPOSE: The aim of this randomized, multicenter, noncomparative, phase II trial 
was to investigate the efficacy and safety of two potential first-line 
treatments, capecitabine and oxaliplatin (CapOX) plus bevacizumab (BEV) and 
capecitabine and irinotecan (CapIRI) plus bevacizumab, in Japanese patients with 
metastatic colorectal cancer (mCRC).
PATIENTS AND METHODS: Patients with untreated mCRC were randomly assigned to 
receive either CapOX plus bevacizumab (CapOX/BEV arm: bevacizumab 7.5 mg/kg and 
oxaliplatin 130 mg/m2 on day 1 and oral capecitabine 2,000 mg/m2 on days 1-14, 
every 3 weeks) or CapIRI plus bevacizumab (CapIRI/BEV arm: bevacizumab 7.5 mg/kg 
and irinotecan 200 mg/m2 on day 1 and capecitabine 1,600 mg/m2 on days 1-14, 
every 3 weeks). The primary endpoint was overall response rate (ORR), and the 
secondary endpoints included progression-free survival (PFS), overall survival 
(OS), and safety.
RESULTS: A total of 107 patients were enrolled. The intent-to-treat population 
comprised 54 patients in the CapOX/BEV arm and 53 patients in the CapIRI/BEV 
arm. The median follow-up period was 35.5 months. ORR was 56% in the CapOX/BEV 
arm and 55% in the CapIRI/BEV arm. Median PFS and OS were 12.4 and 26.7 months 
in the CapOX/BEV arm and 11.5 and 28.7 months in the CapIRI/BEV arm, 
respectively. The frequencies of hematological and nonhematological adverse 
events above grade 3 were 13% and 30% in the CapOX/BEV arm and 25% and 23% in 
the CapIRI/BEV arm, respectively.
CONCLUSION: CapOX plus bevacizumab and CapIRI plus bevacizumab are equally 
effective and feasible as the first-line treatments in Japanese patients with 
mCRC.
IMPLICATIONS FOR PRACTICE: The CCOG-1201 study was designed to evaluate the 
efficacy and safety of capecitabine and oxaliplatin plus bevacizumab and 
capecitabine and irinotecan plus bevacizumab as a first-line treatment in 
Japanese patients with metastatic colorectal cancer. This article reports on the 
trial and efforts to define the role of these regimens, including the effect of 
KRAS status and UGT1A1 polymorphisms in metastatic colorectal cancer.