Monoclonal Antibodies Plus Chemotherapy Not Cost-Effective for Colorectal Cancer

Combining monoclonal antibodies with chemotherapy may not be the most cost-effective strategy of treating patients with RAS wild-type metastatic colorectal cancer (CRC), according to study findings published in Clinical Therapeutics.

Researchers conducted a systematic review of the literature published up until October 2021 in PubMed, EMBASE, the Cochrane Library, the international HTA database, and Ichushi-Web. They selected 15 out of 591 identified studies that analyzed either the cost-effectiveness or cost-utility of using monoclonal antibodies, which included various combinations of bevacizumab, panitumumab, and cetuximab along with chemotherapy as first-line treatments for RAS wild-type metastatic CRC.

The researchers factored into account life-years gained, quality-adjusted life-years gained, willingness-to-pay thresholds, funding, incremental costs, and annual discount rates to determine the incremental cost-effectiveness ratio (ICER). This ratio was calculated based on the difference in average cost over the difference in average effects of 2 treatments. Cost-effectiveness depended on whether the ICER was within the willingness-to-pay threshold determined by each study.

Most of the studies found that chemotherapy alone proved to be more cost-effective than combining a monoclonal antibody with chemotherapy. Only bevacizumab combined with fluoropyrimidine-based chemotherapy was more cost-effective than fluoropyrimidine-based chemotherapy and placebo.

In contrast, this trend was not observed for the combination of cetuximab and chemotherapy, or the combination of panitumumab and chemotherapy compared with chemotherapy alone. This was because the ICERs for the combination treatments exceeded the willingness-to-pay thresholds across 6 different studies.

When evaluating monoclonal antibody and chemotherapy combination treatments against each other, 6 studies compared the cost-effectiveness of cetuximab and chemotherapy vs bevacizumab and chemotherapy. One-half of the studies reported that cetuximab and chemotherapy was more cost-effective than bevacizumab and chemotherapy, while the other half presented conflicting evidence. Most of the discrepancies were due to the fact that bevacizumab treatments typically were lower in cost, but both treatments produced similar effects in terms of quality-adjusted life-years gained.

Five studies compared the cost-effectiveness of panitumumab and chemotherapy vs bevacizumab and chemotherapy. Three studies suggested that panitumumab regimens were more cost-effective than the bevacizumab regimens based on the number of quality-adjusted life-years gained.

Study limitations include the exclusion of conference abstracts and presentations that may have presented more current economic assessments, the lack of cost-minimization or cost-benefit analysis, and potential publication bias as cost-effectiveness analyses are often performed at the request of pharmaceutical companies.

The study authors conclude, “Our study is novel in that it is a cost-effectiveness review that is in line with the current situation in personalized medicine, in which treatment strategies are based on genetic profiles.”

Disclosures: One study author declared affiliations with biotech, pharmaceutical, and/or device companies. Please see original source for full list of disclosures.