Verification of clinical benefit following FDA accelerated approval in oncology: A time-to-event analysis.

e23041 Background: The FDA Accelerated Approval (AA) program enables earlier access to therapies for patients with serious and life-threatening conditions based on a surrogate or intermediate endpoint likely to predict clinical benefit. Sponsors are required to conduct post-approval confirmatory trials to verify clinical benefit in a timely manner. This analysis evaluated the time to verify clinical benefit among oncology indications approved under the AA pathway. Methods: This retrospective observational analysis utilized publicly available data from the U.S. Food and Drug Administration (FDA) Center for Drug Evaluation and Research (CDER) AA report. Data were extracted from the source report and converted to a structured dataset. Indications were classified as oncology or non-oncology and were further categorized as hematologic or solid tumors. Analyses were restricted to oncology indications granted AA before January 31, 2025. Descriptive statistics were used to summarize cohort characteristics. Time to conversion to traditional approval was evaluated using the Kaplan-Meier method, with landmark conversion estimates reported. Differences in time to conversion between hematologic and solid tumor indications were assessed using the log-rank test. Analyses were conducted using R. Results: Among 333 AA records, 227 oncology indications met inclusion criteria. Of the AA indications, 146 (64.3%) were solid tumors and 81 (35.7%) were hematologic malignancies. At the time of the analysis, 132 (58.1%) indications had converted to traditional approval, 60 (26.4%) had not yet converted, and 35 (15.5%) were withdrawn. Median time to conversion was 54.1 months (95% CI: 46.3-63.0). The cumulative probability of conversion was 33.2% (95% CI: 26.3-39.5) at 36 months and 71.4% (95% CI: 62.4-78.2) at 84 months. Among converted indications, time to conversion ranged from 5.5 to 210.6 months. Time to conversion differed significantly between hematologic and solid tumor indications (Χ 2 = 14.9, p = 0.0001). Conclusions: The AA pathway facilitates earlier patient access to oncology therapies; however, time to conversion from accelerated to traditional approval varies widely. The median time to conversion was approximately 4.5 years, with hematologic malignancies converting significantly earlier than solid tumors.