Do drugs approved via expedited approval pathways have therapeutic advantages? A systematic review and meta-analysis

Regulators use expedited approval pathways to speed market approval and patient access to promising new drugs. However, there is uncertainty about whether these pathways are successful in approving drugs with significant therapeutic advantages. This systematic review aims to examine the safety, effectiveness and cost-effectiveness of drugs approved via expedited pathways. Searches were conducted in Medline, Embase and Scopus up to July 2024. Cross-sectional and cohort studies assessing effectiveness, safety and cost-effectiveness of drugs approved via expedited pathways in any jurisdiction were included. Risk of bias was assessed using Joanna Briggs Institute checklists. Where possible, results were meta-analysed; otherwise, narrative synthesis was used. The protocol for this review was registered with PROSPERO: CRD42023444180. Forty-one studies met the inclusion criteria: 36 investigated conditional approval pathways, 16 priority review (14 assessed both pathways) and 3 other pathways. Nineteen studies assessed drug effectiveness, 12 safety and 9 cost-effectiveness. Conditionally approved drugs were no more likely to be of high added clinical value (odds ratio [OR] 1.02; 95% confidence interval [CI] [0.57, 1.82]) but had more post-approval safety concerns (risk ratio [RR] 1.89; 95% CI [1.30, 2.76]) than standard approval drugs; more priority review drugs were of high added clinical value (OR 5.39; 95% CI [3.44, 8.44]) and had more post-approval safety concerns (RR 1.50; 95% CI [1.06, 2.12]). Cost-effectiveness outcomes varied. Study limitations include title and abstract screening conducted by single reviewer, English language only and the lack of published research in low- and middle-income settings. Although these pathways may have successfully sped up the regulatory process, their success in approving drugs that are therapeutic advances is less clear.