(UroToday.com) On the second day of the American Society for Clinical Oncology (ASCO) Genitourinary Cancer Symposium 2023 focussing on urothelial cancer, the Poster Session B: Prostate Cancer and Urothelial Carcinoma included a presentation from Dr. Tiago Costa de Padua presented an analysis of racial and geographic disparities in pivotal bladder cancer clinical trials.
Racial disparities exist across many tumor sites. In urologic oncology, perhaps the best known of these is prostate cancer. However, numerous population-based studies demonstrate a significant racial difference in patient characteristics, incidence, and survival among bladder cancer patients. In particular, incidence rates are noted to be highest among Non-Hispanic whites, followed by black individuals. In addition to these population-based disparities, there is substantial under-representation of Black individuals in oncology clinical trials. Given the recent influx of phase II and III trial in bladder cancer, these authors sought to assess the enrollment disparities in pivotal bladder cancer clinical trials.
To do so, the authors identified published clinical trials as cited in the Bladder Cancer European Society of Medical Oncology (ESMO) guideline, considering the approved drugs and availability in clinical practice. For each of the included trials, the characteristics of participants, including race and geographic location, were collected.
The authors identified 13 phase 2 or 3 trials were identified, evaluating pembrolizumab, atezolizumab, avelumab, erdafitinib, durvalumab +/- tremelimumab and enfortumab vedotin, with a total of 7748 patients. Among these 13 trials, information regarding the racial composition of the study cohort was 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.
Among those with available data, White, Asian and Black patients comprised 71.74% (4716 patients), 19.9% (1313 patients), and 0.66% (44 patients) 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.
Thus, the authors identify that, among contemporary studies of novel treatment approaches in bladder cancer, there is a low rate of race reporting and a very significant under-representation of non-white participants, 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 needs to be actively supported.
Presented by: Tiago Costa de Padua, MD, MSc | IRCCS Ospedale San Raffaele