Racial and geographical disparities in pivotal bladder cancer clinical trials.

454 Background: According to population-based studies, there is a significant racial difference in patient characteristics, incidence, and survival among bladder cancer patients. Non-Hispanic whites have the highest incidence rate, followed by blacks. However, racial clinical trial disparities in clinical research are a critical problem around the world, with an underrepresentation of the black population. In the last years, multiple phase 2/3 trials have introduced the use of immunotherapy and targeted therapy in the treatment of bladder cancer. We aimed to assess the enrollment disparities in pivotal BC clinical trials. Methods: Published clinical trials were identified from the Bladder Cancer European Society of Medical Oncology (ESMO) guideline, considering the approved drugs and availability in clinical practice. The characteristics of participants, including race and geographic location, were collected. Results: A total of 1 phase 2 or 3 trials were identified, evaluating pembrolizumab, atezolizumab, avelumab, erdafitinib, durvalumab +/- tremelimumab and enfortumab vedotin, with a total of 7748 patients. The table summarizes the findings. Race information is available only in 8 of them, 4 in the original report and 4 in the results section of clinicaltrials.gov, with a pooled sample of 6573 patients. White, Asian and Black patients comprised 71.74% (4716 pts), 19.9% (1313 pts), and 0.66% (44 pts) of all patients, respectively. The percentage of white patients ranged from 51.6% to 88.6%, whereas the black population varied from 0.3% to 2.2%. Geographical location information is available only for 2 clinical trials, with a predominance of patients from the United States and Europe and an under-representation of patients from other continents. Conclusions: We observed a low rate of race reporting in bladder cancer published trials and a very significant under-representation of non-white participants in the pivotal trials for bladder cancer, with just 0.66% of black patients. Based on these finding, there are insufficient data to confirm the effectiveness or safety of new drugs in minority groups, especially blacks. To provide generalizable results, race reporting should be always included in licensing trials, and recruitment of black and other minority population to trials should be stimulated.[Table: see text]