OBJECTIVES: The National Institute for Health and Care Excellence (NICE) has the highly specialised technology (HST) appraisal process for rare diseases. However, the HST routing criteria are highly restrictive, resulting in many rare diseases being appraised through the standard STA process. We reviewed a sample of rare disease technology appraisals to explore how manufacturers and committees engage with the current methods for these topics.

METHODS: NICE STAs published after the release of the 2022 NICE methods (N=235), including those currently under-development (N=300), were identified. Interventions were checked for orphan designation status granted by the European Medicines Agency. These topics were further screened to only include topics where the disease prevalence threshold was 5 per 100,000, which corresponds to 2855 patients in England. This resulted in 16 appraisals for rare diseases which did not meet the strict HST routing criteria – these were compared against a sample of 16 other non-rare appraisal topics.

RESULTS: Out of the 16 ‘rare disease’ appraisals identified, 5 included severity modifiers, and 4 included caregiver QALYs. The committee's preferred threshold was reported in 11 appraisals (all between £20K and £30K); of the five that did not report a threshold, two of these were a cost-comparison analysis. One notable finding are the justifications manufacturers use in some topics to make the case for a higher QALY weighting via the severity modifier. In these topics, manufacturers argued that the natural history data is highly uncertain, and therefore, the proportion and absolute shortfall calculations are underestimated.

CONCLUSIONS: Our findings indicate that NICE demonstrates flexibility when assessing treatments for rare diseases via the STA route. However, it would be welcome for NICE to consider reviewing either the routing criteria for HST or provide further details in the methods guide regarding the approaches to be taken for these topics.