{"groups":[{"description":"Participants received pembrolizumab 200 mg intravenously (IV) on Day 1 of each 21-day cycle (Q3W) for up to 35 treatments (approximately 2 years). Eligible participants who stopped the initial course of pembrolizumab due to complete response (CR) or completed initial course of pembrolizumab and had stable disease but progressed after discontinuation, initiated a second course of pembrolizumab at the investigator's discretion for up to 17 cycles (approximately 1 year additional).","id":"FG000","title":"Pembrolizumab"},{"description":"Participants received 1 of 6 possible standard chemotherapy regimens: mFOLFOX6, or mFOLFOX6+bevacizumab 5 mg/kg IV on Day 1 of each 2-week cycle, or mFOLFOX6+cetuximab 400 mg/m\\^2 IV over 2 hours then 250 mg/m\\^2 over 1 hour weekly in each 2-week cycle, or FOLFIRI, or FOLFIRI+bevacizumab 5 mg/kg IV on Day 1 of each 2-week cycle, or FOLFIRI+cetuximab 400 mg/m\\^2 IV over 2 hours then 250 mg/m\\^2 over 1 hour weekly in each 2-week cycle. Participants with documented disease progression following chemotherapy can crossover to receive pembrolizumab for up to 35 cycles (approximately 2 years). Eligible cross over participants who stopped pembrolizumab who stopped pembrolizumab and had stable disease but progressed after discontinuation, initiated a second course of pembrolizumab at the investigator's discretion for up to 17 cycles (approximately 1 year additional).","id":"FG001","title":"Standard of Care (SOC)"}],"periods":[{"dropWithdraws":[{"reasons":[{"groupId":"FG000","numSubjects":"72"},{"groupId":"FG001","numSubjects":"87"}],"type":"Death"},{"reasons":[{"groupId":"FG000","numSubjects":"5"},{"groupId":"FG001","numSubjects":"0"}],"type":"Lost to Follow-up"},{"reasons":[{"groupId":"FG000","numSubjects":"0"},{"groupId":"FG001","numSubjects":"2"}],"type":"Physician Decision"},{"reasons":[{"groupId":"FG000","numSubjects":"2"},{"groupId":"FG001","numSubjects":"10"}],"type":"Withdrawal by Subject"},{"reasons":[{"groupId":"FG000","numSubjects":"74"},{"groupId":"FG001","numSubjects":"55"}],"type":"Sponsor decision"}],"milestones":[{"achievements":[{"groupId":"FG000","numSubjects":"153"},{"groupId":"FG001","numSubjects":"154"}],"type":"STARTED"},{"achievements":[{"groupId":"FG000","numSubjects":"153"},{"groupId":"FG001","numSubjects":"143"}],"type":"Treated"},{"achievements":[{"groupId":"FG000","numSubjects":"12"},{"groupId":"FG001","numSubjects":"5"}],"type":"Received Second Course of Pembrolizumab"},{"achievements":[{"groupId":"FG000","numSubjects":"0"},{"groupId":"FG001","numSubjects":"7"}],"type":"Switched Over to Pembrolizumab"},{"achievements":[{"groupId":"FG000","numSubjects":"0"},{"groupId":"FG001","numSubjects":"0"}],"type":"COMPLETED"},{"achievements":[{"groupId":"FG000","numSubjects":"153"},{"groupId":"FG001","numSubjects":"154"}],"type":"NOT COMPLETED"}],"title":"Overall Study"}],"preAssignmentDetails":"Of the 307 participants randomized in the study, 296 participants received study medication and were evaluable for safety analyses."}