Presentation (CTI)

OBJECTIVES: Adherence to pharmacotherapies influences real-world treatment effectiveness when compared to clinical trial outcomes. Cost-effectiveness analyses using clinical trial data often exclude adherence, as trials are not representative of real-world behavior. This study evaluates how adherence affects the cost-effectiveness of inclisiran compared with PCSK9 inhibitors (PCSK9is) alirocumab and evolocumab in ASCVD patients.
METHODS: The analysis is based on a Markov model from the England and Wales payer perspective. The patient cohort was divided by adherence levels into high (≥80%), intermediate (50-79%), and low (≤50%) based on proportion of days covered (PDC). Adherence distributions were derived from 2022-2023 U.S. Komodo Health data. LDL-C reduction was adjusted based on adherence using a previously published study. Adherence-adjusted LDL-C reductions were applied to baseline estimates from a published network meta-analysis. Cost-effectiveness was modeled over patients’ lifetime.
RESULTS: Among inclisiran treated patients, 79%, 11.9%, and 9.1% were in the high, intermediate, and low adherence categories, respectively. For PCSK9is these values were 56.0%, 16.9% and 27.1% respectively. Without adherence adjustment, inclisiran was dominant (less costly, more effective) over alirocumab, with a QALY gain of 0.02 and £31,303 in cost offsets. Compared to evolocumab, inclisiran had a QALY loss of 0.02 and had a cost offset of £32,119. With adherence adjustment, inclisiran was dominant over both, gaining 0.10 QALYs vs. alirocumab and 0.07 vs. evolocumab, with cost offsets of £30,763 and £31,536, respectively.
CONCLUSIONS: Inclisiran achieved improved cost-effectiveness estimates against both PCSK9is when adherence was included in the model. These findings underscore the importance of incorporating adherence into health economic evaluations to better inform payer decision-making.