The chimeric antigen receptor (CAR) T-cell therapy idecabtagene vicleucel may offer an overall survival benefit in patients with multiple myeloma, regardless of their race or ethnicity, according to a novel study published by Peres et al in Blood Advances.
Background
Multiple myeloma—a cancer of the plasma cells in the bone marrow—is the second most common hematologic malignancy in the United States and the most common hematologic malignancy among Black and Hispanic populations. The disease has an overall 5-year survival rate of 56%. Although several treatments exist, multiple myeloma remains incurable, and most patients who achieve remission eventually experience relapse.
In CAR T-cell therapies, physicians remove patients’ T cells from their blood, add a gene for a receptor that binds to a specific tumor protein to help the T cells find and destroy the cancer cells, and infuse the modified cells back into the patient. In March 2021, idecabtagene vicleucel became the first CAR T-cell therapy to gain approval from the U.S. Food and Drug Administration (FDA) to treat patients with relapsed and refractory multiple myeloma.
“Non-Hispanic Black individuals are twice as likely to develop multiple myeloma compared [with] their White counterparts,” stressed lead study author Laura Peres, PhD, an epidemiologist at the Moffit Cancer Center. “We also know that Black patients are less likely to receive these novel CAR-T therapies and are less represented in clinical trials. So, with this study, we wanted to look at how outcomes differ between racial and ethnic groups,” she added.
Study Methods and Results
In the new retrospective study, investigators used the U.S. Multiple Myeloma Immunotherapy Consortium to identify 207 patients with multiple myeloma—72% (n = 149) of whom identified as non-Hispanic White, 17% (n = 30) of whom identified as non-Hispanic Black, and 11% (n = 22) of whom identified as Hispanic. The investigators then analyzed the remission rates, overall survival, and prevalence of complications associated with CAR T-cell therapy in the patients with relapsed or refractory multiple myeloma who received idecabtagene vicleucel.
After a follow-up of 9 months posttreatment, the investigators found that the non-Hispanic Black patients (97%) were more likely to develop cytokine-release syndrome compared with non-Hispanic White patients (85%) and Hispanic patients (77%). However, they did not find any statistically significant differences in the patients’ risk of developing severe complications, incidence of intensive care unit admissions, likelihood of reaching complete remission when comparing outcomes by race and ethnicity. Further, there were no statistically significant differences in the overall survival rates between Black and White patients.
Although the overall response rates were lower among Hispanic patients compared with non-Hispanic Black patients and non-Hispanic White patients, the investigators suggested that these findings may be attributed to the limited number of Hispanic patients involved in the study.
Conclusions
“These results highlight the need for diverse patient cohorts in research and clinical trials. Clinical trials often lack diversity for many reasons such as recruitment barriers, financial considerations, medical mistrust, and cultural insensitivity. [S]tringent trial eligibility criteria also often exclude racial and ethnic minorities. In fact, 75% of our study population would not have been eligible for the trial that led to FDA approval of [idecabtagene vicleucel]. A lack of clinical trial representation can limit underrepresented groups’ access to life-saving care,” emphasized Dr. Peres.
“With this study, we see that Black and White patients with multiple myeloma both respond well to [idecabtagene vicleucel]. We hope that these findings encourage the use of [idecabtagene vicleucel] in all patients with multiple myeloma,” she concluded.
Disclosure: For full disclosures of the study authors, visit ashpublications.org.
