Use of surrogate endpoints in health technology assessment: a review of selected NICE technology appraisals in oncology

Objectives Surrogate endpoints, used to substitute for and predict final clinical outcomes, are increasingly being used to support submissions to health technology assessment agencies. The increase in the use of surrogate endpoints has been accompanied by literature describing the frameworks and statistical methods to ensure their robust validation. The aim of this review was to assess how surrogate endpoints have recently been used in oncology technology appraisals by the National Institute for Health and Care Excellence (NICE) in England and Wales.Methods This article identifies technology appraisals in oncology published by NICE between February 2022 and May 2023. Data are extracted on the use and validation of surrogate endpoints including purpose, evidence base, and methods used.Results Of the 47 technology appraisals in oncology available for review, 18 (38 percent) utilized surrogate endpoints, with 37 separate surrogate endpoints being discussed. However, the evidence supporting the validity of the surrogate relationship varied significantly across putative surrogate relationships with 11 providing randomized controlled trial evidence, 7 providing evidence from observational studies, 12 based on the clinical opinion, and 7 providing no evidence for the use of surrogate endpoints.Conclusions This review supports the assertion that surrogate endpoints are frequently used in oncology technology appraisals in England and Wales and despite the increasing availability of statistical methods and guidance on appropriate validation of surrogate endpoints, this review highlights that use and validation of surrogate endpoints can vary between technology appraisals, which can lead to uncertainty in decision making.