Preliminary Efficacy and Safety of Camrelizumab in Combination With XELOX Plus Bevacizumab or Regorafenib in Patients With Metastatic Colorectal Cancer: A Retrospective Study

Hong Zhou,Wenjie Cai,Yanfang Lin,Xiaomeng He,Xiaofeng Li,Yuehui Wang

doi:10.3389/fonc.2021.774445

Abstract

BackgroundFor a majority of patients with metastatic colorectal cancer (mCRC) with MS stable (MSS) or mismatch repair proficient (pMMR), the role of immunotherapy is undetermined. This study investigated the efficacy and safety of camrelizumab when added to XELOX chemotherapy plus bevacizumab or regorafenib as first-line therapy for mCRC.Materials and MethodsMedical records of mCRC patients who received camrelizumab and XELOX plus bevacizumab or regorafenib at the First Hospital of Quanzhou Affiliated to Fujian Medical University between June 1, 2019, and April 30, 2021, were retrospectively collected. The objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and side effects of the drug were recorded and reviewed.ResultsTwenty-five eligible patients received combination therapy, including bevacizumab in 19 patients and regorafenib in 6. Twenty-one patients had pMMR/MSS and one MSI-H. Of the 25 patients who could be evaluated for efficacy, 18 (72%) achieved PR, 6 (24%) achieved SD, and 1 (4%) achieved PD. The ORR and DCR were 72% (18/25) and 96% (24/25), respectively. The median progression-free survival (PFS) was 11.2 months (95% CI 8.9–13.9), and OS had not yet been reached. The combination regimen of regorafenib in six (24%) patients was unassociated with treatment outcomes. Most AEs were either grade 1 or 2, and treatment-related grade 3 toxicities were observed in 8/25 (32%) patients.ConclusionCamrelizumab combined with XELOX plus bevacizumab or regorafenib was feasible, producing high rates of responses as first-line therapy in unselected Chinese patients with MSS mCRC. The toxicities were generally tolerable and manageable. Prospective randomized trials with large sample sizes are needed to evaluate these findings.

Highlights

Immune checkpoint inhibitors (ICIs) have been shown to benefit patients with metastatic colorectal cancer with mismatch repair deficiency or high microsatellite instability (MSI-H) [1, 2]
Camrelizumab is one of the most widely used antiPD-1 antibodies for various solid tumors in real-time practice owing to drug accessibility and economic pressure for patients in China
We evaluated the efficacy and safety of camrelizumab when added to the first-line XELOX chemotherapy with bevacizumab or regorafenib in patients with metastatic colorectal cancer

Summary

Introduction

Immune checkpoint inhibitors (ICIs) have been shown to benefit patients with metastatic colorectal cancer (mCRC) with mismatch repair deficiency (dMMR) or high microsatellite instability (MSI-H) [1, 2]. In the REGONIVO study [5], regorafenib combined with nivolumab produced an ORR of 33% (95% CI, 15.6% to 55.3%) in 24 patients with pMMR/MSS refractory mCRC, indicating that anti-angiogenic drugs may enhance the efficacy of immune checkpoint inhibitors. Camrelizumab is one of the most widely used antiPD-1 antibodies for various solid tumors in real-time practice owing to drug accessibility and economic pressure for patients in China It has shown promising clinical efficacy in several kinds of solid tumors, based on positive efficacy results in clinical trials [8,9,10,11], and has been shown to be effective in MSI-H/dMMR solid tumors [12]. This study investigated the efficacy and safety of camrelizumab when added to XELOX chemotherapy plus bevacizumab or regorafenib as first-line therapy for mCRC

Methods

Results

Conclusion