Study Finds ICI Outcomes Differ by Ethnic/Racial Background

The development of immune checkpoint inhibitors (ICIs) has revolutionized cancer treatment since the first agents were approved to treat melanoma in 2011.¹ In multiple solid tumors, programmed death 1 (PD-1) and programmed death ligand 1 (PD-L1) have been successfully targeted in treatment.¹ In non–small-cell lung cancer (NSCLC), PD-1 and PD-L1 inhibitors have been found to improve survival and since 2015 have become standard of care.¹

Despite this advancement, disparities persist in cancer diagnosis and treatment delivery for patients with advanced or metastatic cancer.¹ Most cancer-related phase 3 clinical trials fail to report patient ethnicity. Moreover, <25% of participants in cancer-related clinical trials are racial minorities.¹

To understand this disparity and the presence of immune-related adverse events, a retrospective analysis on all patients with NSCLC treated with ICIs from 2014 to 2020 at 3 hospitals in Los Angeles, CA, was performed by Resnick and colleagues. They identified 186 patients with NSCLC who were treated with ICIs. The average body mass index was 25.1 and the mean participant age was 66 years. Asian/Pacific Islander represented 34.9% of participants, non-Hispanic white 32.2%, Hispanic/Latino 17.7%, black/African American 9.7%, and 5.4% reported other.

The all-group progression-free survival (PFS) was 7.1 months, and the overall survival (OS) was 17.3 months. For Asian/Pacific Islanders, the PFS was 18.7 months, and the OS was 20.3 months. For non-Hispanic white patients, the PFS was 7.37 months, and the OS was 25.3 months. For Hispanic patients, the PFS was 4.1 months, and the OS was 11.0 months. Black/African American patients had a PFS of 7.2 months, and the OS was 24.4 months for this patient group.

The rate of immune-related adverse events was 36%, with grade 1-2 adverse events accounting for 68.7% and grade 3 and above 31.3%. Hispanic/Latino patients had a 24.2% rate of adverse events, Asian/Pacific Islanders 41.5%, non-Hispanic white patients 41.7%, and black/African American patients 22.2%. The endocrine system was involved in 28.4% of adverse events followed by 19.4% dermatologic and 17.9% gastrointestinal systems. Steroids were given to 23.9% of the patients experiencing immune-related adverse events.

For the group overall, the presence of immune-related adverse events was significantly associated with improved median PFS and OS. When OS was examined, the degree of improvement was statistically significant by ethnic/racial group.

Reference:

1. Florez MA, Kemnade JO, Chen N, et al. Persistent ethnicity-associated disparity in antitumor effectiveness of immune checkpoint inhibitors despite equal access. Cancer Res Commun. 2022;2(8):806-813.

Source: Resnick K, Zang P, Larsen T, et al. Impact of ethnicity and immune-related adverse events (IRAE) on outcomes for non-small cell lung cancer (NSCLC) patients treated with immune checkpoint inhibitors. J Clin Oncol. 2022;40(suppl 16):e21115.