Despite a higher prevalence of triple-negative breast cancer (TNBC) among Black women compared to white women, Black women are underrepresented in TNBC clinical trials, particularly those involving novel immunotherapies.
In a study published today in Clinical Cancer Research, researchers at Yale Cancer Center used data from a previous study showing that the combination of durvalumab and neoadjuvant chemotherapy was well tolerated and resulted in high pathologic complete response (pCR) rate in women with non-metastatic TNBC before surgery to recruit another group of racially diverse patients to see if the results were the same. Durvalumab is an immunotherapeutic that targets the PD-1/PD-L1 immune checkpoint pathway.
“In the initial study, the patient population did not reflect the racial/ethnic makeup of our surrounding community nor of the overall disease population,” said Lajos Pusztai, MD, DPhil, professor of medicine (medical oncology) and senior author on the study. “The low accrual of ethnic minorities, particularly Black Americans, in clinical trials is problematic for several reasons. It means Black patients are not given equitable access to potentially life-saving new treatments and it limits our ability to study potential differences in drug metabolism, toxicity, and efficacy between populations with different ancestries.”
In the study led by first-author Julia Foldi, MD, a former Medical Oncology-Hematology fellow at Yale Cancer Center, 67 patients were included, of whom 21 (31 percent) identified as Black, bringing the proportion of Black patients closer to that of the community. 40 patients identified as non-Hispanic white, three as Hispanic/Latino, and three as Asian. Patient characteristics and baseline tumor features did not differ dramatically by race. Among the 67 patients enrolled, 31 (46 percent) had a pCR to neoadjuvant durvalumab plus chemotherapy. There were no statistically significant differences by race: 43 percent of Black patients had a pCR compared with 48 percent of non-Black patients.
In both the Black and non-Black groups, patients who had a pCR had significantly longer event-free survival and overall survival than those who did not have a pCR. Three-year overall survival rates were 96.8 percent for patients with a pCR and 81.8 percent for those without. Three-year event-free survival rates were 90.3 percent and 66.7 percent among those with a pCR and those without, respectively.
“This study underscores the importance of including all demographics in clinical trials and that underserved populations can and should be included. Our study demonstrates that if patients are given similar treatment and similar follow-up, the differences in outcomes between Black and non-Black patients are reduced,” said Dr. Pusztai. “By improving healthcare access and delivery, we could mitigate some of the healthcare disparities that exist in our society.”
The study was supported by AstraZeneca, a Komen Leadership Grant (SAC 160076), and an R01 grant from the National Cancer Institute of the National Institutes of Health (1R01CA219647-01).
Additional Yale authors include: Adriana Kahn, Andrea Silber, Tao Qing, Neal Fischbach, Justin Persico, Kerin Adelson, Anamika Katoch, Anees Chagpar, Tristen Park, Adam Blanchard, Kim Blenman, and David L. Rimm.