Minorities Remain Underrepresented in ICI Cancer Trials

TOPLINE:

Racial and ethnic minority groups, particularly Hispanic/Latinx and Black patients, remain underrepresented in immune checkpoint inhibitor (ICI) cancer trials, although recent years have shown an upward trend in the representation of these groups.

METHODOLOGY:

• Historically, there have been disparities in the representation of racial and ethnic minority groups in all phases of cancer clinical trials. These disparities may be even more pronounced in trials involving novel therapies such as ICIs.
• Researchers examined 471 ICI clinical trials published between 2007 and 2022. Most trials (68%) were published between 2019 and 2022, with the highest number of publications in 2020 (23%). The majority of trials were conducted as phase 2 (41%) or phase 3 (26%) studies.
• The enrollment-incidence ratio (EIR) was calculated to compare the proportion of racial/ethnic minority group patients in US-based trials with age-adjusted cancer incidence data available for the US population. An EIR above 1 indicated overrepresentation, whereas an EIR below 1 indicated underrepresentation.
• More than half of the trials (51%) recruited patients internationally, including the United States; 37% recruited from study sites within the United States only; and 12% recruited from sites outside the United States.
• Data on racial and ethnic composition were extracted from published papers or ClinicalTrials.gov, and differences in participation by publication year, ICI agent, and cancer site were analyzed.

TAKEAWAY:

• Of the 471 trials examined, 45% reported data on racial composition. Only 5% reported Hispanic/Latinx ethnicity in published papers as a separate category from race, and another 5% reported it together with race.
• In US-only trials, White patients were overrepresented (EIR, 1.20), whereas Hispanic/Latinx patients were the most underrepresented (EIR, 0.35), followed by Black patients (EIR, 0.66). American Indian/Alaska Native patients constituted only 0.2% of the trial population and were underrepresented, though researchers noted the figure was not statistically significant (EIR, 0.72; 95% CI, 0.33-1.21).
• Subgroup analyses indicated consistent overrepresentation of White patients across publication years (EIR, 1.19-1.24), ICI classes, and cancer sites, whereas Hispanic/Latinx patients were consistently underrepresented.
• However, an upward trend in trial representation and reporting was observed for all minoritized racial/ethnic groups over time (trend P values, < .05), with American Indian/Alaska Native patients and Black patients experiencing a small but statistically significant average annual percentage increase in representation of 0.06 and 0.04, respectively, across all years.

IN PRACTICE:

“Our findings underscore the continuous need to address disparities in cancer clinical trial representation and reporting to ensure equitable access to novel cancer treatments such as ICls,” the authors wrote.

“Concerted efforts from policymakers, institutions, clinicians, researchers, patients, and advocates are necessary to improve diversity in trial enrollment and reporting to better understand treatment efficacy and safety across all patient populations.”

SOURCE:

The study was led by Alfredo V. Chua Jr, MD, Roswell Park Comprehensive Cancer Center in Buffalo, New York. It was published online on August 22, 2024, in JCO Oncology Practice.

LIMITATIONS:

The study’s limitations included the use of delayed-adjusted incidence rates from the Surveillance, Epidemiology, and End Results (SEER) database, which only provided data up to 2020. This may have affected the accuracy of the EIR calculations. Additionally, the SEER data combined Asian and Pacific Islander patients into one group, potentially masking differences between these populations. The study also noted that cancer incidence in American Indian/Alaska Native patients is underreported, leading to less reliable estimates for this group.

DISCLOSURES:

Xin-Wei Huang disclosed employment with Merck and the Roswell Park Comprehensive Cancer Center. Shipra Gandhi reported receiving honoraria from OncLive/MJH Life Sciences and consulting fees from Hologic/Biotheranostics, AstraZeneca, Novartis, and MedPage Today. Igor Puzanov disclosed stock ownership in IDEAYA Biosciences and Compugen and consulting roles with Iovance Biotherapeutics and Nouscom. Prantesh Jain reported employment with Athenex and consulting roles with Amgen and Boehringer Ingelheim. Additional disclosures are noted in the original article.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.