Health technology assessment (HTA): Decisions on treatment efficiency guided by clinical judgement and pharmacoeconomics.

Over the past 25 years, the UK has adopted health technology assessment (HTA) as a mechanism to ensure that new medicines, and new indications for existing medicines, are assessed in an open, objective and robust way so that when the UK National Health Service (NHS) adopts these therapeutic developments, it does so in a cost-effective manner, accepting those agents with an acceptable cost per quality-adjusted life year (QALY) or a discount that brings the cost below the threshold. Usually, pharmacoeconomic modelling is used to justify pricing, often relying on surrogate endpoints or extrapolation beyond the duration of existing trials data. Although cost-effectiveness is often based on robust clinical trials, there are other issues to consider, which require an understanding of clinical pharmacology and clinical judgement. Key considerations include the justification of use of surrogates and extrapolation, the appropriateness of any comparator drug studied, the difference between efficacy in trials and clinical effectiveness in real-world use, the additional costs of providing a service to deliver the medicine, and the cost of any important adverse effects that are likely to occur. Although the process in the UK is now well established, with support from clinicians and the public, there remain questions about whether the currently accepted cost/QALY is set too high, whether a special case should be made for some drugs commanding a higher cost/QALY (such as in cancer and end-of-life situations), and whether HTA should be used more broadly to assess other activities undertaken by the NHS.