Efficacy and Safety of Maintenance Therapy Using Cetuximab in Patients with Metastatic Colorectal Cancer: Retrospective Study

Cancer Manag Res. 2024 Mar 19:16:185-197. doi: 10.2147/CMAR.S443666. eCollection 2024.

Abstract

Purpose: Cetuximab (CET) combined with chemotherapy significantly improved the survival in RAS and RAF wild-type metastatic colorectal cancer (mCRC) patients, while clinical evidence was lacking on the use of maintenance therapy (MT). The study aimed to explore the role of maintenance therapy following Cetuximab + chemotherapy and the optimal Cetuximab-based maintenance therapy regimen.

Patients and methods: We retrospectively reviewed data on the efficacy and safety of CET-based MT in patients with mCRC who achieved disease control after induction therapy.

Results: Eighty-one patients with mCRC who achieved disease control after CET + chemotherapy induction were enrolled. Overall median progression-free survival (PFS) was 10.5 (95% CI = 8.8-12.2) months and median maintenance/observation PFS (mnPFS) was 6.0 (95% CI = 5.0-7.0) months. Among these 81 patients, 61 patients were prescribed MT (CET alone for 21 patients and CET + chemotherapy for 40 patients). Median PFS and mnPFS in the MT group were significantly longer than those for the non-MT group. Different MT regimens did not affect PFS and mnPFS significantly. Univariate and multivariate analysis demonstrated MT, complete response/partial response during induction therapy, and absence of peritoneal metastasis to be positively associated with longer PFS and mnPFS. Treatment-related adverse events (AEs) were tolerable during MT, and AE-related deaths were not observed.

Conclusion: MT with CET or CET + chemotherapy was an appropriate option following initial induction chemotherapy for patients with RAS and RAF wild-type mCRC. This strategy endowed survival benefits and a tolerable safety profile.

Keywords: RAS and RAF wild-type; cetuximab; colorectal cancer; maintenance therapy; targeted therapy.

Grants and funding

This research received no external funding.