National Institute for Health and Care Excellence

meet the definition of an HST, as described in legislation in Schedule 4 of the NHS Commissioning Board and Clinical Commissioning Groups (Responsibilities and Standing Rules) Regulations 2012, or may potentially need nationally coordinated delivery approaches, and

need consideration using the methods and processes of the HST Programme, as identified through the HST routing criteria.

small numbers of patients

limited or no treatment options

challenges for research and difficulties with collecting evidence because of the uniqueness of the disease.

encourage research on, and innovation for, ultra-rare diseases when there are challenges in generating an evidence base that is robust enough to bring the product to market

secure fairer and more equitable treatment access for very small populations with ultra-rare diseases

recognise that an approach that maximises health gain for the NHS may not always be acceptable because it could deliver results that are not equitable.

It is important for NICE to apply appropriate constraints to the ultra-rare diseases' populations who can potentially be routed to the HST Programme. This is because the HST Programme is a deliberate departure from the standard technology appraisal process. It values the benefits of HSTs more by having a much higher incremental cost-effectiveness ratio (ICER) threshold for the reasons outlined above.

Each time NICE routes a topic to the HST Programme and if the technology is recommended, it is deciding that the NHS must commit to allocating resources that would otherwise have been used for activities that would be expected to generate greater health benefits.

NICE has sought to strike a balance between the desirability of supporting access to treatments for ultra-rare diseases against the resulting inevitable reduction in overall health gain across the NHS. Both considerations are valid and important, and neither can be given absolute priority over the other. So, the HST routing criteria and their anticipated application do not intentionally seek to capture every case in which there are challenges in generating an evidence base, or when there is a small population with an ultra-rare disease.

This approach ensures that technologies routed to the HST Programme fulfil the vision of the programme and manages the displacement in the wider NHS. How the context of the HST vision is linked to the HST routing criteria is illustrated in figure 1.