605P - First-line chemotherapy with or without targeted therapies in metastatic colorectal cancer: The GEMCAD 14-01 prospective cohort

Background

First-line randomized clinical trials in metastatic colorectal cancer (mCRC) comparing chemotherapy with doublets (CT) plus targeted therapies (bevacizumab, cetuximab and panitumumab) (TT), have shown substantial benefit in progression free survival but modest benefit in overall survival over CT alone. In addition, elderly patients (pts) and pts with ECOG performance status (PS) of 2 are usually under-represented. GEMCAD 1401 is a prospective observational, multicenter study (GEMCAD 1401. ClinicalTrials.gov identifier: NCT02254941), that compared overall survival benefit in treatment naïve mCRC pts, treated with or without first-line TT.

Methods

Between June 2014 and June 2018, 1107, mCRC pts were included and 1020 were eligible (640 pts treated with CT plus TT and 380 pts treated with CT alone). Baseline pts characteristics that would influence initial treatment strategy decision and efficacy (age, gender, tumor stage at diagnoses, primary tumor side, surgery of primary tumor, RAS and BRAF status, ECOG PS, Charlson score, number and type of affected organs, leucocyte, alkaline phosphatase, lactate dehydrogenase and CEA level) and postbaseline variables (time-varying covariates; ECOG PS, Charlson score, lactate dehydrogenase and grade 3-4 toxicities), were balanced using Inverse Probability Treatment Weighting (IPTW).

Results

After IPTW application, standardized differences of all basal variables between groups were <10%. The median overall survival was 21.2 months 95% confidence interval (CI) (18.9-23.6) in the CT plus TT group and 21.4 months (95% CI 18.2-25.3) in the CT group (hazard ratio (HR) for death, 0.93; 95% CI 0.8-1.08). The median progression free survival was 9.9 months (95% CI 9.3-10.7) in the CT plus TT and 8.9 months in the CT alone (95% CI 8.1-9.7). HR 0.87 (95% CI 0.76- 0.99).

Conclusions

First-line treatment with CT alone compared with CT plus TT, show no detrimental effect in overall survival.

Clinical trial identification

NCT02254941.

Editorial acknowledgement

Legal entity responsible for the study

Grupo Español Multidisciplinar en Cáncer digestivo.

Funding

Estudio Clínico: Beca FIS - Ayuda de Proyectos de Investigación en Salud del Instituto Carlos Tercero, convocatoria del a ño 2013 . Expediente Nº PI13/01728 and an unrestrictive economic supports from GEMCAD group Subestudio de biomarcadores asociado: Beca FIS - Ayuda de Proyectos de Investigación en Salud del Instituto Carlos Tercero, convocatoria del a ño 2013 . Expediente PI13/01659.

Disclosure

J. Feliu: Financial Interests, Personal, Advisory Role: Roche, Amgen, AstraZeneca. A. Ruiz-Casado: Financial Interests, Personal, Invited Speaker: Servier, Abbott, Nestle, Medtronic; Financial Interests, Personal, Advisory Board: Pierre Fabre, Amgen. J. Aparicio: Financial Interests, Personal, Speaker, Consultant, Advisor: Amgen, Bayer, Merck, MSD, Pierre Fabre, Servier. J. Gallego Plazas: Financial Interests, Personal, Advisory Board: AAA, Amgen, Bayer, Bristol Myers Squibb, Eisai, Ipsen, Lilly, Merck, MSD, Pierre Fabre, Roche, Servier; Financial Interests, Personal, Invited Speaker: AAA, Amgen, Bayer, Bristol Myers Squibb, Ipsen, Lilly, Merck, MSD, Novartis, Servier; Financial Interests, Personal, Other, Educational: Amgen, Ipsen, Merck, Novartis, Pierre Fabre, Roche; Financial Interests, Institutional, Funding: Astellas, AstraZeneca, Bristol Myers Squibb, Daiichi Sankyo, Lilly, Servier; Non-Financial Interests, , Member of Board of Directors: Spanish Society Medical Oncology, Spanish Group Of Neuroendocrine an Endocrine Tumours; Non-Financial Interests, , Project Lead: AGAMENON-SEOM Registry of Esophagohastric Cancer. R. Leno: Financial Interests, Personal, Speaker, Consultant, Advisor: Servier, Ipsen, MSD, Sanofi, Merck, Amgen. All other authors have declared no conflicts of interest.