Assessing the Contribution of Components in Late-Phase Oncology Trials: A Roadmap of Key Approaches.

Incorporating Clinical Outcome Assessments (COAs) in oncology trials is essential for evaluating therapeutic benefits and balancing survival with quality of life and symptom management. Understanding COA adoption trends and gaps is especially critical in neuro-oncology due to the complex symptom profiles of neuro-oncology patients. We reviewed neuro-oncology trials in ClinicalTrials.gov, identifying COA instruments using the PROQOLID database. We analyzed trends in COA usage, associations with trial characteristics, and the impact of key regulatory and advocacy efforts using correlation and regression analyses. Of 1,874 adult interventional neuro-oncology trials with sufficient data, 85% were early-phase, 91% treatment-focused, primarily studying glioblastomas (61%), and unspecified gliomas (42%); 16% used COAs, with 127 distinct instruments reported; of these trials, 71% used Patient Reported Outcomes, 46% used Clinician-Reported Outcomes, with other categories of COAs used by fewer than 12% of the trials. COA use was more likely in later-phase trials (OR = 1.38, P <.00001), supportive care trials (OR > 1, P <.01), studies on novel versus FDA-approved interventions (OR = 1.72, P <.00001), single- versus multi-arm trials (OR = 1.62, P =.027), and randomized versus nonrandomized trials (OR = 3.28, P <.00001). COA incorporation increased over time (R = 0.77, P <.00001), especially in treatment-focused trials (R = 0.88, P <.00001) and across all COA types except composite measures. Our computational assessment highlights low but increasing COA adoption in neuro-oncology trials, mirroring broader oncology trends and reflecting a cumulative impact of regulatory and advocacy efforts. Priority areas for improvement include early-phase trials, FDA-approved interventions, and treatment-focused studies. Our findings emphasize the need for COA-specific reporting improvements and greater standardization in neuro-oncology research.