Real-World Outcomes of Axi-cel for LBCL by Race and Ethnicity

Despite several clinical trials of chimeric antigen receptor T-cell (CAR-T) therapies and real-world studies published to date, there are limited data on outcomes by race and ethnicity. Outcomes by race and ethnicity among patients with large B-cell lymphoma (LBCL) who received axicabtagene ciloleucel (axi-cel) in the real-world setting were presented at the 2022 American Society for Clinical Oncology Annual Meeting.

Patients with LBCL were identified from a non-interventional post-authorization safety study as having received commercial axi-cel between October 2017 and August 2020. Race (African American or Asian vs White) and ethnicity (Hispanic vs non-Hispanic) were self-reported. Patients were excluded if they were enrolled in clinical trials, had received prior nontransplant cellular therapy (including CAR-T therapy), had primary central nervous system lymphoma, were without reported comorbidities, or had no efficacy or safety follow-up. Median follow-up was 12.7 months (mo). Outcomes included overall response rate (ORR), complete response (CR) rate, duration of response (DOR), progression-free survival (PFS), overall survival (OS), grade ≥3 cytokine release syndrome (CRS), and grade ≥3 immune effector cell–associated neurotoxicity syndrome (ICANS). ORR and CR were evaluated in patients with ≥18 days of follow-up. Kaplan-Meier estimates were calculated for PFS and OS. Multivariate logistic and Cox regression models were used to assess the associations of race and ethnicity with efficacy and safety end points of interest, while adjusting for other potential risk factors.

Of 1389 patients, 1127 (81%) were White, 70 (5%) were African American, and 81 (6%) were Asian; 152 (11%) were Hispanic, including 104 White, 2 Black, and 1 Asian Hispanic. African-American patients, compared to White patients, were more likely to be <65 years (40% vs 24%), more likely to have pulmonary impairment (41% vs 28%), and more likely to receive axi-cel ≥12 mo from diagnosis (71% vs 59%). Among patients with ≥180 days of follow-up, ORR was 74% (CR, 57%; 12-mo PFS, 48%; 12-mo OS, 63%) for White patients, 57% (CR, 45%; 12-mo PFS, 36%; 12-mo OS, 62%) for African-American patients, 67% (CR, 53%; 12-mo PFS, 55%; 12-mo OS, 65%) for Asian patients, 73% (CR, 55%; 12-mo PFS, 50%; 12-mo OS, 65%) for Hispanic patients. No significant differences were found in OS and PFS across races, nor in any efficacy outcome between Hispanic and non-Hispanic patients.

Being classified as African American was associated with inferior ORR (odds ratio [OR], 0.40; 95% confidence interval [CI], 0.24-0.69) and CR rate (OR, 0.55; 95% CI, 0.32-0.93) compared with White patients. The 6-mo DOR rate was 70% in White patients, 66% in African-American patients, 81% in Asian patients, and 71% in Hispanic patients. Asian patients had a favorable DOR compared with both White (hazard ratio [HR], 0.46; 95% CI, 0.24-0.87) and African-American patients (HR, 0.39; 95% CI, 0.17-0.88). Grade ≥3 CRS and ICANS occurred in 7% and 18% of African-American patients, 10% and 19% of Asian patients, and 8% and 27% of White patients, respectively. Hispanic patients had lower rates of grade ≥3 CRS and ICANS (4% and 15%) compared with non-Hispanic patients (9% and 27%). Asian patients had a lower risk of grade ≥3 ICANS compared to White patients (OR, 0.52; 95% CI, 0.29-0.96), and Hispanic patients had a lower risk compared to non-Hispanic patients (OR, 0.51; 95% CI, 0.31-0.85).

Overall, outcomes with axi-cel in patients with relapsed or refractory LBCL were consistent in the real-world setting, regardless of race or ethnicity. No differences in efficacy outcomes were observed for Hispanic patients compared to non-Hispanic patients. However, lower response rates in African-American patients compared to White patients were observed. This discrepancy warrants further dissection of possible underlying factors, such as higher disease burden and differential access to care.

Source

Locke FL, Siddiqi T, Jacobson CA, et al. Real-world outcomes of axicabtagene ciloleucel for the treatment of large B-cell lymphoma by race and ethnicity. J Clin Oncol. 2022;40:16. Abstract 7571.