The Impact of Survival Benefit and Study Design on FDA Approval for Anticancer Drugs Over the Past Decades

Despite the tremendous effort in the oncology community, the success rate of anticancer development remained low at 30% to 40% from the Phase 3 study to the regulatory approval. The factors associated with the regulatory approval for market authorization have gained interest in the community to improve the success rate of drug development. Using the data from 208 Phase 3 studies for anticancer drugs, we explored the possible factors associated with the US Food and Drug Administration's (FDA's) approval by multivariate logistic regression analysis. The model incorporated 21 factors from therapeutic context, study design, and outcomes. The hazard ratio (HR) for overall survival (OS) showed a significant association with FDA approval (coefficient: -29.907, P < .001), and the age of control drugs in the market followed (coefficient: -2.581, P = .008). In the model, if the HR for OS changes from 0.75 to 0.85, the probability of FDA approval remarkably decreases from 79.6% to 16.4%. A 50% likelihood of FDA approval is predicted at HR 0.795 for OS. Furthermore, the P-value for the OS test and the width of the confidence interval on HR for OS showed a significant association with the probability of FDA approval. These findings consistently underscore the rigorous standard required for new anticancer drugs to obtain regulatory approval from the FDA.