ABSTRACT
BACKGROUND: Today, there are many treatment options available for the management of ulcerative colitis, creating challenges in selecting the most efficacious and cost-effective treatment sequences. Treatments in the anti-tumor necrosis factor alpha (TNFα) therapeutic class, as well as vedolizumab, are widely used and endorsed as first-line options according to treatment guidelines. The aim of this study was to compare treatment sequences involving vedolizumab and the anti-TNFα treatment adalimumab in terms of cost-effectiveness in the treatment of moderately to severely active ulcerative colitis in Italy. METHODS: A cost-effectiveness model comparing treatment sequences within the Italian National Health Service in terms of costs and quality-adjusted life years (QALYs) with a lifetime horizon was developed. The analysis focused on the relative positioning of vedolizumab and adalimumab, leveraging the results of the landmark head-to-head VARSITY clinical trial as key inputs. The robustness of the results was investigated through a range of sensitivity and scenario analyses. RESULTS: The strategy of vedolizumab as a first-line advanced therapy followed by adalimumab was associated with higher costs and health benefits compared with first-line adalimumab followed by vedolizumab. The incremental cost-effectiveness ratio was 16,146/QALY, which was found to be robust to changes to inputs associated with areas of high uncertainty. CONCLUSION: This economic evaluation estimated a 94% probability that vedolizumab as a first-line advanced therapy is cost-effective at a threshold of 33,004/QALY when compared with first-line adalimumab sequences. Using clinical trial evidence to inform the efficacy of second-line treatments estimated that the effectiveness of anti-TNFα treatments is not substantially reduced by vedolizumab exposure.
ABSTRACT
AIMS: Approximately, 4% of Stage IV colorectal cancers (CRC) are microsatellite instability-high (MSI-H)/deficient mismatch repair (dMMR) tumors. Patients with metastatic MSI-H/dMMR CRC receiving conventional therapies experience lower response rates and tend to have worse overall survival compared with patients with microsatellite stable (MSS)/proficient mismatch repair (pMMR) CRC. Pembrolizumab received FDA approval in 2020 for first-line treatment of Stage IV MSI-H/dMMR CRC based on significantly longer progression-free survival versus standard of care (SoC, 5-fluorouracil-based therapy with or without bevacizumab or cetuximab). This study evaluated the cost-effectiveness of pembrolizumab vs. SoC as per KEYNOTE-177 and other first-line treatments for MSI-H/dMMR CRC from a US healthcare system perspective. METHODS: A three-health-state partitioned-survival model was built using progression-free and overall survival data from KEYNOTE-177 and a network meta-analysis. Utilities were derived from KEYNOTE-177 EQ-5D-3L data. Drug acquisition, administration, AE, surgery, monitoring, subsequent treatment, and terminal care costs were included. Sensitivity and scenario analyses were performed, including utilizing a state-transition model structure and adopting a societal perspective. RESULTS: Over a lifetime time horizon, pembrolizumab and SoC were associated with total QALYs of 4.85 and 3.23, and total costs of $381,735 and $370,465, respectively, resulting in an ICER of $6,984 per QALY. QALY gains were mainly driven by extended survival with pembrolizumab. Pembrolizumab incurred higher drug acquisition costs relative to SoC but was cost-saving in terms of drug administration, AE, monitoring, subsequent treatment, and terminal care. Pembrolizumab dominated FOLFOX + panitumumab, FOLFOXIRI, and FOLFOXIRI + bevacizumab, and presented ICERs of $35,220 and $276 against XELOX and XELOX + bevacizumab. Results were robust to sensitivity and scenario analyses. CONCLUSION: Pembrolizumab is highly cost-effective for the first-line treatment of unresectable or metastatic MSI-H/dMMR CRC in the US at a willingness-to-pay threshold of $100,000/QALY.Key messagesPembrolizumab is a highly cost-effective option for the first-line treatment of patients with unresectable or metastatic MSI-H/dMMR colorectal cancer in the United States at a willingness-to-pay threshold of $100,000. Compared with the current standard of care for these patients, pembrolizumab:Increases survival due to delaying and preventing progression;Increases QALYs due to longer survival, improvement in HRQoL in the progression-free health state, and fewer Grade 3+ adverse events;Reduces costs associated with administering treatment, managing adverse events, monitoring post-progression disease, providing subsequent treatment, and providing terminal care; andReduces indirect health care costs when taking a societal perspective due to productivity gains from delaying and preventing progression and death, less frequent treatment administration and less frequent Grade 3+ adverse events.