Variation in toxicity reporting methods for early phase lung cancer treatment trials at oncology conferences

Abstract Introduction Phase I and II trials provide the initial human safety and tolerability data for new drugs. However, the methods for presenting toxicity data are not standardized. Clinicians often first encounter these data at professional conferences. We sought to characterize how the burden of adverse events (AE) is reported at the largest professional conference in clinical oncology. Methods We collected toxicity data from all lung cancer-associated phase I and II trial presentations and posters at the American Society for Clinical Oncology annual meetings 2017-2019. We captured AE features including the minimum incidence utilized for reporting; whether AEs shown were treatment-emergent or treatment-related, grouped by organ system or separated by individual descriptors; whether combined or separated across dose levels when a dose escalation component was included; and whether dose-limiting toxicities, serious AE, dose reduction rules and denominators for laboratory tests were described. Results 209 trials were analyzed. There was wide variability in toxicity reporting practices. Six different thresholds for reporting AE of any grade were used. Treatment-related AEs were reported twice as frequently as treatment-emergent AEs. Toxicities were as likely to be reported across dose level as by dose level. Terms such as dose-limiting toxicity and serious AE were rarely defined. Dose reduction rules and denominators for laboratory tests were never defined. Conclusion Standardization of methods for reporting toxicities could improve the quality and ease of comparability of data on adverse effects in early phase therapeutic trials. A minimal AE data disclosure template is proposed.