Background <p>The introduction of biosimilars can lead to substantial price reductions which can alter cost-effectiveness conclusions in health technology assessments. This study, undertaken for the National Institute for Health and Care Excellence (NICE), aimed to pilot a test-and-learn approach for biosimilars appraisals whilst pragmatically assessing the cost-effectiveness of bevacizumab (originator and biosimilars) plus fluoropyrimidine-based chemotherapy versus chemotherapy alone for patients with metastatic colorectal cancer.</p> Methods <p>A partitioned survival model with three health states (progression-free, post-progression and dead) was used. No additional active lines of treatment were modelled assuming that all further treatments were cost-effective and assuming no interaction between bevacizumab and the efficacy of subsequent treatments. Analyses were undertaken independently for the use of bevacizumab plus fluoropyrimidine-based chemotherapy as first-line, and second-line, treatment. Analyses were conducted in line with NICE guidance. The clinical effectiveness of treatments was estimated from reviews of previous NICE technology appraisals, published literature, and expert input. Confidential prices of bevacizumab weighted by the market share were used.</p> Results <p>The use of bevacizumab plus fluoropyrimidine-based chemotherapy was shown to extend life and increase quality-adjusted life-years (QALYs). Whilst cost per QALY values cannot be reported due to confidentiality reasons, the NICE Appraisal Committee stated that these were below what NICE considers a cost-effective use of resources for both first- and second-line treatment.</p> Conclusions <p>The pragmatic modelling approach piloted was accepted by NICE and allowed for a quicker, internally funded, appraisal of bevacizumab biosimilars; this approach likely can be extended to other biosimilar appraisals.</p>