Efficacy and safety of regorafenib or fruquintinib plus camrelizumab in patients with microsatellite stable and/or proficient mismatch repair metastatic colorectal cancer: an observational pilot study

This study was to investigate the efficacy and safety of regorafenib or fruquintinib combined with camrelizumab in patients with microsatellite stable (MSS) and/or proficient mismatch repair (pMMR) metastatic colorectal cancer (mCRC). Medical records of MSS/pMMR mCRC patients who received regorafenib (80 mg) or fruquintinib (3 mg) once a day (21 days on/7 days off) plus camrelizumab (200 mg) every three weeks in Yuhuangding Hospital between January 2020 and June 2020 were retrospectively collected. Follow-up data up to November 1st, 2020 was gathered. The primary endpoint was the objective response rate (ORR) and disease control rate (DCR). The safety profile was the secondary endpoint. A total of 16 patients were enrolled. The ORR was 25.0% (4/16) and the DCR was 62.5% (10/16). The main adverse events (AEs) included reactive cutaneous capillary endothelial proliferation (RCCEP) (81.3%), fatigue (43.8%), hypertension (37.5%), hand-foot skin reaction (25.0%), and thyroid dysfunction (25.0%). Most AEs were grade 1 or 2, with only 1 patient of grade 3 liver dysfunction. All the AEs were ameliorated by effective symptomatic treatment. Regorafenib or fruquintinib plus camrelizumab exhibited promising efficacy in patients with MSS/pMMR mCRC. The toxicity was moderate and manageable.

Automated summary

This study investigated the efficacy and safety of regorafenib or fruquintinib combined with camrelizumab in treating patients with microsatellite stable and/or proficient mismatch repair metastatic colorectal cancer. The combination therapy showed promising efficacy with manageable toxicity, and common adverse events included RCCEP, fatigue, hypertension, hand-foot skin reaction, and thyroid dysfunction.