Clinical trials for Alzheimer’s drugs omit key populations

Racial and ethnic groups most at risk for Alzheimer's disease are underrepresented in U.S. clinical trials, according to UIC research.

Zhuoer Lin, an assistant professor in the School of Public Health, led a study analyzing patient populations in U.S. clinical trials for Alzheimer's treatments. He found that almost half of the trials did not report on race or ethnicity at all, and of those that did, more than 90% of participants identified as white. Comparatively few patients identified as Black, Hispanic, Native American and Asian or Pacific Islander.

Such a gap limits researchers' understanding of how new treatments affect underrepresented populations, many of whom have a higher risk, statistically, for Alzheimer's disease than white older adults do. Compared to white older adults, Black older adults are twice as likely to develop the neurodegenerative disease. For Hispanic older adults, the risk is 1.5 times more.

"Especially in a country as diverse as the U.S., clinical trials need to represent all populations," Lin said.

Lin and his colleagues looked at 71 clinical trials for Alzheimer's disease treatments conducted in the U.S. between 1997 and 2023. All were Phase 3 clinical trials: the final level of drug testing before FDA approval.

The researchers scanned the trials for any reporting on participants' race and ethnicity, including the language used to describe participants' race and ethnicity and whether any critical discussion was included (for example, if the report acknowledged any inequities present).

Of the 36 trials that did report on participants' race or ethnicity, that reporting was inconsistent. Yet it was clear that white patients made up 91.3% of participants in these trials.

Of the 36 trials with race and ethnicity information, 20 included Black participants, 13 included Hispanic participants, 11 had Asian or Pacific Islander participants and two had Native American participants.

None of the trials included in-depth discussion of how treatment safety or efficacy may vary across races and ethnicities.

Lin said these findings urge active recruitment to make clinical trials more inclusive of people in the U.S. with Alzheimer's disease. For example, trials could be made more inclusive with supports such as transportation to testing sites, language translation services, financial compensation for participants, culturally conscious staff and outreach materials tailored to specific populations.

"Implementing these changes requires coordinated, multilevel efforts from the research community," Lin said. "We want to raise a call to action for better practice, reporting and analysis focused on racial and ethnic differences."