Effcacy and toxicity of regorafenib compared to reintrodaction of chemotherapy in metastatic colon cancer: retrospective multicenter study

The objective of the study is to compare effectiveness various systemic therapies in 3rd and subsequent lines therapy metastatic colon cancer. Material Methods . Retrospective multicenter collected data from 2 clinics Russian Federation. We considered overall survival (OS) as main criterion effectiveness. Progression-free (PFS) was additional criterion. performed a single- multifactorial analysis effect parameters on PFS. To evaluate regorafenib reintroduction previously effective drugs, we should prove equivalence line chemotherapy (CT) targeted 6-month survival, provided that boundaries would be between 0.8 1.25. reach 0.05 probability type I error 80 % power, 178 patients (89 each group) included study. Results database identifed 215 with morphologically confrmed cancer who received two or more antitumor drug 2010 2021. selected 132 history 83 used regimen treatment. median OS groups did not differ (HR, 1.01; 95 CI, 0.7–1.45; p=0.920); were 74 70 %, respectively. signifcantly higher group 1.94; 1.3–2.7; p<0.001). Multivariate showed previous treatment regimens kept its independent positive PFS 1.9; 1.3–2.8; In our study, toxicity CT developed 117 (54.4 %) frequent group: 67.4 (89/132) vs 33.7 (28/83) repeated administration (p<0.001). Conclusion Regorafenib survival. treatment, lower toxicity.