Wagner, Andrea

767 Background: The CORRECT trial (NCT01103323) showed that REG improves overall survival (OS) vs placebo (PBO) in patients with mCRC who failed approved therapies (OS HR 0.77; 1-sided p=0.0052; Grothey 2013). A total of 760 patients were randomized to REG (n=505) or PBO (n=255) in more than 100 centers across North America, Europe, Asia, and Australia. We conducted a post-hoc exploratory subgroup analysis of the 83 (11%) patients from 18 US centers. Methods: Eligible patients had an ECOG PS ≤1 and had received approved therapies, including a fluoropyrimidine, oxaliplatin, irinotecan, and bevacizumab, and if KRAS wild-type cetuximab and/or panitumumab. Data from the overall cohort, including US patients, are provided for perspective. Descriptive statistics are shown. Results: Of the 83 US patients, 36 (43%) were randomized to PBO and 47 (57%) to REG. Baseline characteristics of the US group were consistent with the overall cohort: median age in the US was 58 yr (range, 34 – 85) vs 61 (22 – 85) overall, 49% of US patients were ECOG PS1 (vs 46%), and 46% received ≤ 3 treatments for mCRC (vs 52%). KRAS status mutant/wild-type was 57%/34% in the US vs 57%/39% overall. All patients in the trial had prior bevacizumab and 57% of US patients also had prior cetuximab and/or panitumumab (vs 51% overall). However, higher proportion of patients in the US were Black (11% vs 2%), KRAS status unknown (10% vs 4%), and had colon as the primary disease site (82% vs 65%). Mean percentages of planned REG dose were similar (76% US vs 79% overall) and mean REG treatment duration was 3.1 mos in US vs 2.8 mos overall. Rates of dose modifications REG/PBO were 87%/47% in the US vs 76%/38% overall and grade ≥3 adverse events REG/PBO were 74%/64% vs 78%/49%, respectively. Based on 44 total death events, the HR for OS in the US subgroup was 0.46 (95%CI 0.25 – 0.84) favoring REG; median OS was 4.7 mos for PBO, but could not be estimated for REG due to censored data. However, this analysis was based on a relatively small sample size and event count. Conclusions: Patients treated in the CORRECT study in the US appear similar to the overall cohort and results are generally consistent with the overall findings of the trial. Clinical trial information: NCT01103323.