Post-Market Evidence for Cancer Medicines in Regulatory and Clinical Decision-Making: A Scoping Review.

Background: Cancer medicines usually have uncertain efficacy and safety profiles when they are first approved by medicines regulators because this evidence usually emerges post-market. Little is known about the extent to which post-market evidence is evaluated and integrated into evidence review processes in regulatory and clinical contexts.

Objectives: The objective of this scoping review is to examine the literature on how post-market evidence on benefits and harms is evaluated and integrated in regulatory decisions and guidance for clinical decision-making.

Methods: This scoping review focussed on the organisations that review cancer medicines and post-market evidence for their benefits and harms. It examined all regulatory or clinical contexts in which this post-market evidence might be included in evidence review processes for evaluation then integration into regulatory or clinical contexts. Four electronic databases were searched. Titles and abstracts were screened for all retrieved references followed by full-text screening by two independent reviewers according to pre-specified inclusion criteria.

Results: In total, 28 studies met inclusion criteria. These included 31 assessments by medicines regulators, four by clinical practice guideline developers and two by health technology assessment agencies. Half of the studies evaluated clinical outcomes for benefit or harms (e.g., overall survival, serious adverse events). We found that more published literature evaluated and integrated post-market evidence for benefits and harms of cancer medicines in regulatory than in clinical situations, such as treatment guidelines and health technology assessments. In these studies, post-market evidence for harms seemed to be integrated more often than for benefits. And the studies showed a gap: only some of the evaluated post-market evidence was subsequently integrated in both regulatory and clinical situations.

Conclusion: Overall, these findings raise important questions around the availability, accessibility, and assessment of post-market evidence for benefits and harms of cancer medicines so that it can be used by health professionals working in cancer services and by people with cancer.