Kenneth A. Getz

New data suggests that under-representation of minority volunteers in clinical trials has a lot to do with the race and ethnicity of the clinical research investigator. This is one of the major findings of a study that my colleague, Laura Faden, and I recently completed. The Tufts Center for the Study of Drug Development (Tufts CSDD) study found that minority physicians participate in clinical research far less often than their white counterparts—most notably in FDA-regulated clinical trials funded by industry. Whereas 9.3% of all white physicians actively participate as principal investigators in industry-funded clinical trials, only 3.7% of minority physicians do.

Although minority physicians are no less interested in participating in clinical research than white physicians, minority investigators tend to conduct and initiate only about half the number of trials annually as their white counterparts. They're also younger and have a more limited clinical research infrastructure.

"The discrepancy between government- and industry-funded trials should come as no surprise," said Priscilla Igho-Pemu, MD, MS, director of clinical trials in the Clinical Research Center at Atlanta's Morehouse School of Medicine. "Only trials funded by the National Institutes of Health (NIH) are required to involve minorities. If not, you need a strong scientific rationale to not include them...not just that it's inconvenient or they're slow to recruit or noncompliant."

Since the mandate went into effect in 1993, the NIH has "constantly refined inclusion requirements [and] monitored and publicly reported progress toward more balanced representation," commented Alfonso Alanis, MD, chairman and chief executive officer of Anaclim, an Indianapolis, IN-based clinical research organization that specializes in minority participation. The regulations, he believes, drove a lot of positive change in NIH-funded clinical research.

"Minorities are woefully underrepresented even in studies of diseases, like diabetes, that disproportionately affect them," explained Alanis. To not have proper representation of impacted populations creates issues of scientific integrity and relevance. "There is now ample evidence that different racial and ethnic groups can respond differently to the same treatments. Given the significant growth of minority populations in the U.S., exclusion is also hard to justify from a social justice perspective," he said. According to the U.S. Census Bureau, by the year 2050, more than half of the U.S. population will be comprised of minority communities, up from 37% in 2004.

The commonly held belief that under-representation of minority volunteers in clinical trials is due to the legacy of Tuskegee and distrust of the research establishment was challenged by a December 2005 PLoS Medicine article, conducted by David Wendler, PhD, and his colleagues. "We found that minorities are at least as willing to participate in clinical research studies as long as they are eligible, know about it, and are invited to volunteer," said Wendler, director of the unit on vulnerable populations in the department of bioethics at the NIH. Wendler believes the largest barrier to minority participation is access. "A lot of studies are conducted largely by white investigators in inaccessible places to many minorities," said Wendler. There are also a host of socioeconomic barriers, including the inability to take time off from work or to afford the transportation costs.

"In inner city Baltimore, it has been relatively easy to attract male African-Americans to participate in research at the National Institute of Drug Abuse simply because that's their home turf," Wendler said.