Keywords: Cancer, patient-reported outcome, function, open-label
As patient-focused drug development is increasingly highlighted, careful analysis and interpretation of PRO data is required to inform regulatory decisions. Recent analyses by FDA have shown that most contemporary cancer trials submitted to FDA are single arm or open-label randomized trials. Given that patients will be aware of treatment assignment in over half of the trials collecting PRO data, it is imperative to undertake research to characterize what the effect of open-label trials may have on PRO responses. The FDA has been undertaking research into characterizing potential open-label bias in PRO measurement, and the proposed panel session intends to describe current research efforts and lessons learned. Research topics that are being explored include evaluating which PRO domains may be most susceptible to open-label bias as well as understanding the possible means by which open-label bias may occur. Our evaluation for domains has focused on functional domains (emotional, role, and physical) as well as global quality of life. In addition, we are looking at the impact of asymmetric between-arm PRO completion in open-label trials, and its impact on different functional domains. We are evaluating whether patient pre-treatment baseline assessments differ if collected prior to or after randomization. Finally, we have undertaken a retrospective study looking at paired open-label and blinded trials of the same drug and disease context to assess whether patients in the open label investigational arm may overestimate treatment benefit as measured by PRO compared to a paired blinded investigational arm.