As reported in the Journal of Clinical Oncology by Pietrantonio et al, overall survival analysis in the phase III CodeBreaK 300 trial showed numeric improvement with sotorasib/panitumumab vs investigator's choice of treatment in patients with chemorefractory KRAS G12C-mutant metastatic colorectal cancer. In the primary analysis of the trial, sotorasib 960 mg plus panitumumab significantly improved progression-free survival vs investigator's choice of trifluridine/tipiracil or regorafenib.
Study Details
In the international trial, 160 patients were randomly assigned 1:1:1 between April 2022 and March 2023 to receive sotorasib 960 mg plus panitumumab (n = 53); sotorasib 240 mg plus panitumumab (n = 53); or investigator's choice of treatment (n = 54 assigned therapy [n = 51 received therapy]: trifluridine/tipiracil = 37, regorafenib = 14).
Key Findings
After a median follow-up of 13.6 months, death had occurred in 24 patients in the sotorasib 960 mg plus panitumumab group (hazard ratio [HR] vs investigator's choice group = 0.70, 95% confidence interval [CI] = 0.41–1.18, P = .20), 28 patients in the sotorasib 240 mg plus panitumumab group (HR vs investigator's choice group = 0.83, 95% CI = 0.49–1.39, P = .50), and 30 patients in the investigator's choice group.
Updated objective response rates were 30.2%, 7.5%, and 1.9%, respectively; outcomes were not formally statistically analyzed due to absence of significance in overall survival analysis.
No new safety signals were observed.
The investigators concluded, “Although not statistically significant, the observed [overall survival] HR and [objective response rate] along with prior [progression-free survival] and safety findings support sotorasib 960 mg plus panitumumab as a standard of care in patients with chemorefractory KRAS G12C [metastatic colorectal cancer].”
Marwan G. Fakih, MD, Medical Oncology & Therapeutics Research, City of Hope Comprehensive Cancer Center, Duarte, CA, is the corresponding author for the Journal of Clinical Oncology article.
Disclosure: The study was supported by Amgen Inc. For full disclosures of all study authors, visit the Journal of Clinical Oncology.
