OBJECTIVES: To compare health technology assessment outcomes for rare disease therapies from the Institute for Clinical and Economic Review (ICER) and National Institute for Health and Care Excellence (NICE).

METHODS: The ICER website was searched in January 2024 for completed assessments of rare disease therapies from 2017-present. Corresponding NICE appraisals, submitted under Highly Specialized Technology (HST) or Single Technology Appraisals (STA) processes, for the same rare disease therapies were identified. Reports were reviewed for final recommendations, cost-effectiveness at willingness-to-pay (WTP) thresholds, societal perspectives, and caregiver costs/utilities.

RESULTS: A total of 25 completed ICER assessments were included, of which 18 had corresponding NICE appraisals (5 HST, 13 STA). Final NICE recommendations were available for 7 appraisals; the remaining 11 were ongoing, discontinued, or terminated. Of the 7 therapies included, ICER considered none to be cost-effective at the highest WTP thresholds and required significant discounts to reach value-based pricing benchmarks. Six therapies were recommended by NICE, with 4 demonstrating cost-effectiveness under the relevant STA or HST WTP thresholds (some with commercial discounts); of the remaining 2, positive recommendation was based on wider societal benefit (qualitatively, not in economic model). In line with the ultra-rare disease framework, societal perspectives for economic modelling were included in all 7 ICER assessments, but only 2 NICE appraisals (scenario analyses only). Caregiver costs were more frequently included in ICER assessments (n=6) compared with NICE appraisals (n=2), while caregiver utilities were less common (n=3 vs. n=4).

CONCLUSIONS: Rare disease therapies face significant challenges with cost-effectiveness demonstration under the ICER framework despite being more likely to qualify for distinct assessment criteria for rare diseases. While some methodological differences highlight the divergence in outcomes between ICER and NICE, the inclusion of caregiver utilities and the consideration of societal benefits (qualitative or quantitative) can positively impact the outcome at both agencies.