Bevacizumab Biosimilar Equally Effective in Metastatic Colorectal Cancer

The biosimilar version of bevacizumab (Encoda) was found to be equally effective in treating metastatic colorectal cancer (mCRC) when compared with reference bevacizumab (Avastin), according to a study published in Clinical Medicine Insights: Oncology.¹

CRC is among the most common cancers worldwide while also possessing a high fatality rate, especially in cases that become metastatic. Bevacizumab is a monoclonal antibody that is used to treat mCRC that targets vascular endothelial growth factor (VEGF). Biosimilar bevacizumab was approved in China in 2019 and can provide a more affordable option for patients with mCRC, as biosimilars generally cost up to 50% less than reference products.² This study aimed to assess the safety and efficacy of the biosimilar when compared with reference bevacizumab when treated for mCRC. Both treatments were combined with backbone chemotherapy.

Patients from the Fudan University Shanghai Cancer Center and the Zhongshan Hospital Fudan University were considered for this study. Patients who had unresectable mCRC, had received backbone chemotherapy combined with either reference or biosimilar bevacizumab between April 2021 and December 2022, had the standard dose of the medication, and had an Eastern Cooperative Oncology Group performance status (ECOG PS) of 2 or less were eligible for the study. Those who refused to enroll in the study or who had been a part of an intervention study within the previous 4 weeks.

Biosimilar bevacizumab was equally effective in treatment of metastatic colorectal cancer | Image credit: SewcreamStudio - stock.adobe.com

Both medications were administered intravenously at a 7.5 mg/kg dose on a cycle of 21 days. This was combined with a 5 mg/kg dose of backbone chemotherapy given on a cycle of 14 days. The overall response rate (ORR) of this treatment was the primary endpoint of the study, with progression-free survival (PFS) acting as the secondary endpoint, defined as the time of initiation to death, final follow-up, or onset of progressive disease.

There were 436 patients enrolled in the study, of which 234 received the biosimilar and 202 received the reference. A median (range) follow-up time of 14.1 (1.0-35.9) months was observed for the cohort. The median age was 60 years overall and 59.2% of the participants were men. Baseline characteristics, demographics, and exposure to either biosimilar or reference bevacizumab were not significantly different between the 2 groups.

The ORR in the biosimilar group was 42.3% (95% CI, 35.9% to 48.9%) with 2 patients achieving complete response and 97 achieving partial response. The ORR in the bevacizumab group was 42.1% (95% CI, 35.2% to 49.2%) with 1 patient achieving complete response and 84 patients achieving partial response. No significant difference in median PFS interval was found between the 2 groups, with the biosimilar group having a duration of 11.2 months (95% CI, 9.01-13.39) compared with 10.4 months (95% CI, 8.89-11.91) in the reference group.

Adverse events related to treatment had an incidence of 83.7% in all enrolled patients with 23.9% classified as grade 3 or higher. The incidence of adverse events related to treatment were not significantly different between the 2 groups. The most common adverse events included neutropenia, leukopenia, thrombocytopenia, an increase in aspartate transaminase, and anemia.

There were some limitations to this study. Safety data being derived from electronic health record could have led to missing relevant information. The sample size was also restricted int his study.

The researchers concluded that biosimilar bevacizumab was equally effective as a first-line treatment for mCRC as the reference drug, with a similar safety profile found between the 2 groups. “Notably, bevacizumab biosimilar provides additional therapeutic options for patients with mCRC, particularly in economically disadvantaged regions,” the authors wrote.

References

1. Shan H, Wang M, Huang S, Liu H, Liu J, Du Q. Efficacy and safety of bevacizumab biosimilar (Encoda) compared with reference bevacizumab (Avastin) in patients with metastatic colorectal cancer: a multicenter, real-world study. Clin Med Insights Oncol. Published online December 11, 2024. doi:10.1177/11795549241303726
2. Biosimilars can significantly reduce employer pharmacy costs. Are you missing out? Kaiser Permanente. October 24, 2023. Accessed December 16, 2024. https://business.kaiserpermanente.org/california/healthy-employees/pharmacy/biosimilar-reduce-costs