HTA Barriers for Conditional Approval Drugs

Conditional approval pathways facilitate accelerated marketing authorisation based on immature clinical evidence for drugs that address an unmet medical need in a life-threatening or chronically debilitating condition. Lowering evidence requirements for marketing authorisation results in higher clinical uncertainty, which may present challenges for the health technology assessment (HTA) of these products.

The objective of this study is to assess whether conditionally approved drugs face higher probabilities of HTA rejection or delays in HTA approval relative to drugs with standard marketing authorisation.

This paper adopts a mixed-methods approach to provide a meta-analysis of HTA outcomes across 80 drug-indication pairs in France, England, Scotland and Canada. Differences in the characteristics (i.e. disease rarity and clinical trial design) of conditionally approved drugs and drugs with standard marketing authorisation and drivers of HTA outcomes are assessed through logistics regressions. Delays in HTA approval are assessed through a survival analysis.

Relative to standard approval drugs, conditionally approved drugs are less likely to include phase III trial designs, less likely to include clinical endpoints and less likely to include an active comparator. Uncertainties in clinical and economic evidence are raised more frequently by HTA agencies for conditionally approved drugs, which have a marginally lower probability of receiving HTA approval relative to drugs with standard approval. Conditionally approved drugs face moderate delays (an average of 6 months) in receiving HTA approval relative to standard approval drugs.

Overall, conditionally approved drugs likely face increased barriers at the HTA level.