PRO claims continue to be approved by FDA, although at a lower rate than previously reported. This may be partly explained by the increase in the number of oncology products with study designs that may not support PRO labeling as per regulatory guidance. The lack of PRO labeling based on secondary endpoints only may be a reflection of sponsors’ reluctance to capture PRO related value messages to regulatory standards when PROs are not required to support the indication. The acceptance of PRO measures developed prior to the release of the PRO guidance for the purpose of labeling reflects ‘regulatory flexibility’ adopted by the FDA reviewers.
