Changes to Registered and Pivotal Clinical Trials after the 2011 Tri-Societies Guidelines for Clinical Endpoints and Response Criteria in Mycosis Fungoides and Sézary Syndrome

Guidelines for mycosis fungoides and Sézary syndrome clinical trials were published in 2011 to standardize endpoint criteria and trial design. Our retrospective cohort study of mycosis fungoides/Sézary syndrome clinical trials registered on ClinicalTrials.gov and pivotal trials supporting drug approvals and label extensions evaluates adherence to these guidelines. Sixty-three trials met our inclusion criteria. In a subpopulation of trials, mean adherence to the guidelines was approximately 60%. When comparing trials that began in the first 6 years after their publication with those that started after, we found no difference in mean adherence (4.12 vs 3.41) (P = .15). Among the 8 pivotal trials supporting new mycosis fungoides or Sézary syndrome systemic therapies from 1990 to 2020, systemic trials published after 2011 were more likely to randomize patients (100 vs 0%, P = .036), perform superiority testing (100 vs 0%, P = .036), and use an intention-to-treat analysis (100 vs 0%, P = .036). The design of trials registered on Clinicaltrials.gov did not change significantly between the first 6 years after the publication of the guidelines and after. This demonstrates that the guidelines are still not consistently implemented across all trials. However, registrational trials were more likely to implement the recommendations.