Systematic review of EU and US product labels containing real world data in support of efficacy claims.

Real-world evidence (RWE) is increasingly included in marketing authorization applications, and plays a growing role in regulatory decision-making. Although commonly included in product labels as safety information, its use for efficacy claims remains limited and randomized controlled trials (RCTs) remain the gold-standard. Regulatory guidance on the use of RWE is expanding, but a significant gap remains regarding its role in labeling, particularly for communicating drug effectiveness. This review examines how real-world evidence (RWE) has been used in many therapeutic areas to support efficacy claims in drug product labels approved by the US Food & Drug Administration (FDA) and the European Medicines Agency (EMA). A systematic search identified 173 brands that included RWE as primary efficacy evidence, as an external comparator to single-arm trials, or as supportive evidence alongside RCTs. This work offers insights for designing RWE studies that support labeling claims and inform regulatory guidance.