Factors related to drug approvals: predictors of outcome?

There is growing interest in characterising factors associated with positive regulatory outcomes for drug marketing authorisations. We assessed empirical studies published over the past 15 years seeking to identify predictive factors. Factors were classified to one of four 'factor clusters': evidentiary support; product or indication characteristics; company experience or strategy; social and regulatory factors. We observed a heterogeneous mix of technical factors (e.g., study designs, clinical evidence of efficacy) and less studied social factors (e.g., company-regulator interactions). We confirmed factors known to be of relevance to drug approval decisions (imperative) and a cohort of less understood (compensatory) social factors. Having robust supportive clinical evidence, addressing rare or serious illness, following scientific advice and prior company experience were associated with positive outcomes, which illustrated the multifactorial nature of regulatory decision making and factors need to be considered holistically while having varying, context-dependent importance.