Background: Phase III trials in metastatic colorectal cancer (mCRC) have collectively led to progressive advancements in patient outcomes over the past decades. This study characterizes the evolution of mCRC phase III trials through assessing the value of cancer therapy, as measured by the ASCO Value Framework. Methods: Phase III trial results of systemic therapy for mCRC published between 1980 and 2015 were identified, and their outcome, statistical significance, journal impact factor, and citation by the 2016 NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for CRC were recorded. For each trial, the net health benefit (NHB) score was calculated using the June 2015 (original) and May 2016 (revised) ASCO Value Framework: Advanced Disease. Results: There were 114 mCRC phase III trials eligible for calculation of the NHB score. Using the revised framework, the median NHB score was 4.6 (range, −30 to 43.5); 12% of trials received bonus points. Trials with statistically significant results had higher NHB scores compared with nonsignificant trials (median NHB score, 21.6 vs 2.9; P<.0001). Clinical trials cited in the NCCN Guidelines had higher NHB scores than those not cited (median score, 8.0 vs 0.3; P=.02). In multivariate linear regression analysis, the only significant predictor of high NHB score was statistically significant studies. Conclusions: The median NHB score for mCRC phase III trials was 4.6. Higher NHB scores are associated with statistically significant studies and are cited in the NCCN Guidelines, a surrogate for practice-changing trials. The 2016 ASCO Value Framework may not fully capture the benefits on an individual patient level.