A phase II study of encorafenib and cetuximab (EC) beyond progression in combination with FOLFIRI in <i>BRAF</i> V600E-mutated metastatic colorectal cancer (mCRC).

M Maria Alessandra Calegari (Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy) L Lisa Salvatore (Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario, Agostino Gemelli, IRCCS, Roma, Italy) M Michele Basso (Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy) M Maria Laura Iaia (Medical Oncology and Palliative Care Department, Azienda Ospedaliera Cardinale G. Panico, Tricase (Lecce), Italy) G Giulia Caira (Medical Oncology, Università Cattolica del Sacro Cuore and Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy) A Alexia Spring (Medical Oncology, Università Cattolica del Sacro Cuore and Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy) G Giovanni Trovato (Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli–IRCCS, Università Cattolica del Sacro Cuore, Rome, Italy) L Luciana Giannone (Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy) M Martina Ventola (Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy) A Antonia Cosmai (Medical Oncology, Università Cattolica del Sacro Cuore and Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy) L Linda Di Francesco (Medical Oncology, Università Cattolica del Sacro Cuore; Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy) M Maria Bensi (Medical Oncology, Università Cattolica del Sacro Cuore and Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy) L Laura Chiofalo (Medical Oncology, Università Cattolica del Sacro Cuore and Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy) P Paola Troisi (Medical Oncology, Università Cattolica del Sacro Cuore and Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario "A. Gemelli," IRCCS, Rome, Italy) A Anna Ceccarelli (Medical Oncology, Università Cattolica del Sacro Cuore and Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy) G Giustina Valente (Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy) C Carmelo Pozzo (Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy) A Alessandra Anna Anna Prete (Oncology Unit 1, Veneto Institute of Oncology IOV - IRCCS, Padova, Italy) F Federica Morano G Giampaolo Tortora

Abstract

TPS3642 Background: BRAF V600E mutation occurs in approximately 10% of metastatic colorectal cancers (mCRC) and confers poor prognosis. While the combination of encorafenib and cetuximab (EC) has demonstrated improved outcomes in previously treated BRAF V600E-mutated mCRC patients (pts), the duration of response remains suboptimal with median progression-free survival (mPFS) of 4.3 months (m). Approximately half of pts (45%) receive subsequent treatment after EC progression, predominantly with chemotherapy (ChT). Data from the safety lead-in (SLI) of the BREAKWATER trial, assessing EC in combination with ChT doublet in the first-line setting, demonstrated manageable safety profile and promising early efficacy signals for EC in combination with FOLFIRI, despite pharmacokinetic interaction. Methods: ECLYPse (NCT06640166; EU CT Number 2023-508615-24-00) is a multicenter, single-arm, phase II study evaluating EC continuation beyond progression in combination with FOLFIRI in pts with BRAF V600E-mutated mCRC who progressed on second-line EC. Key eligibility criteria include: histologically confirmed colorectal adenocarcinoma, BRAF V600E mutation, documented disease progression on EC in second-line setting, benefit to previous treatment with EC (best response: complete response, partial response or stable disease lasting for at least 3 months), measurable disease according to RECIST 1.1 criteria, ECOG PS ≤1, and availability of archival tumor tissue. Patients receive encorafenib 300 mg daily, cetuximab 500mg/m2 iv every 2 weeks, and standard FOLFIRI regimen. The primary endpoint is 6-month PFS rate. Secondary endpoints include PFS, overall survival, duration of response, objective response rate, disease control rate, and safety. Translational analyses include comprehensive genomic profiling on archival tissue and serial ctDNA analysis. Tumor assessment with contrast-enhanced CT scan of thorax, abdomen and pelvis is performed every 8 weeks. Using a single-stage design with one-sided α = 0.05 and 80% power, 25 patients will be enrolled to detect an improvement in 6-month PFS rate from 10% (null hypothesis) to 30% (alternative hypothesis). If at least 7 pts will be alive and not progressing at 6 months, the treatment will be considered sufficiently active to warrant further investigation. The study is currently enrolling at multiple sites in Italy. Clinical trial information: NCT06640166 .

Article Details

Volume / Issue Vol. 43, Issue 16_suppl
Published June 01, 2025
ISSN 0732-183X
Publisher Lippincott Williams & Wilkins

Journal Info

Journal of Clinical Oncology

Lippincott Williams & Wilkins

ISSN: 0732-183X Health Sciences

Authors (20)

M

Maria Alessandra Calegari

Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy

L

Lisa Salvatore

Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario, Agostino Gemelli, IRCCS, Roma, Italy

M

Michele Basso

Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy

M

Maria Laura Iaia

Medical Oncology and Palliative Care Department, Azienda Ospedaliera Cardinale G. Panico, Tricase (Lecce), Italy

G

Giulia Caira

Medical Oncology, Università Cattolica del Sacro Cuore and Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy

A

Alexia Spring

Medical Oncology, Università Cattolica del Sacro Cuore and Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy

G

Giovanni Trovato

Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli–IRCCS, Università Cattolica del Sacro Cuore, Rome, Italy

L

Luciana Giannone

Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy

M

Martina Ventola

Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy

A

Antonia Cosmai

Medical Oncology, Università Cattolica del Sacro Cuore and Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy

L

Linda Di Francesco

Medical Oncology, Università Cattolica del Sacro Cuore; Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy

M

Maria Bensi

Medical Oncology, Università Cattolica del Sacro Cuore and Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy

L

Laura Chiofalo

Medical Oncology, Università Cattolica del Sacro Cuore and Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy

P

Paola Troisi

Medical Oncology, Università Cattolica del Sacro Cuore and Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario "A. Gemelli," IRCCS, Rome, Italy

A

Anna Ceccarelli

Medical Oncology, Università Cattolica del Sacro Cuore and Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy

G

Giustina Valente

Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy

C

Carmelo Pozzo

Medical Oncology, Comprehensive Cancer Center, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy

A

Alessandra Anna Anna Prete

Oncology Unit 1, Veneto Institute of Oncology IOV - IRCCS, Padova, Italy

F

Federica Morano

G

Giampaolo Tortora