By: Loan Pham
The Food and Drug Administration (FDA), on January 12, 2017, released the draft guidance Multiple Endpoints in Clinical Trials for human drugs, including drugs subject to licensing as biological products. This guidance discusses the problems that are commonly seen with the design, analysis, and interpretation of clinical studies that were designed with multiple endpoints.
The guidance is intendedly to help sponsors avoid the likelihood of having false positive results (consumer’s risk) due to the statistical complexity that is inherently involved in clinical trials with multiple endpoints. However, minimizing the sponsor’s risk—which is the probability of concluding that the drug is not effective, when in fact it is—is equally important from the sponsor’s perspective. Note that increasing the sample size may not be able to salvage the study power in case of co-primary endpoints that are not fully independent. This guidance is an extremely helpful reference for designing a sizable clinical study with sufficient power for the planned multiple primary and secondary endpoints.
The success of a clinical trial with multiple endpoints includes but is not limited to the selection of appropriate endpoints and associated statistical method with an end in mind. Obtaining advice from FDA via special protocol assessment (SPA) for study design, clinical endpoints, and statistical analysis plan (SAP) will lead to more successful clinical program.