Discontinuation and nonpublication of osteosarcoma clinical trials: a cross-sectional analysis of ClinicalTrials.gov data.

BACKGROUND: Osteosarcoma is a rare and aggressive malignancy with limited therapeutic advances despite extensive clinical research. Discontinuation and failure to publish trial results contribute to research waste and may delay progress in patient care. We aimed to characterize osteosarcoma clinical trials registered on ClinicalTrials.gov and evaluate factors associated with trial discontinuation and nonpublication. METHODS: We performed a cross-sectional analysis of interventional osteosarcoma trials registered on ClinicalTrials.gov as of July 1, 2025. Trial characteristics, including completion status, publication status, study design, funding source, trial phase, and enrollment size, were extracted. Multivariable logistic regression was performed to identify factors associated with trial discontinuation and nonpublication. RESULTS: Among 210 eligible trials, 62 (29.5%) were discontinued before completion, and only 26 (17.6%) had published results. Smaller trials were more frequently discontinued and unpublished compared with larger trials. Multicenter trials demonstrated higher publication rates and were independently associated with lower odds of nonpublication (OR = 0.291, 95% CI 0.098-0.859; p = 0.025). No significant associations were observed between funding source, intervention type, or trial phase and trial outcomes. CONCLUSIONS: Nearly one-third of osteosarcoma clinical trials are discontinued, and most completed trials lack published results, highlighting substantial research waste and limitations in evidence generation. Strengthening trial completion strategies, promoting multicenter collaboration, and improving transparency through mandatory results reporting may enhance the efficiency and impact of osteosarcoma research.