Analysis: Lack of diversity dogs trials

By OLGA PIERCE, UPI Health Business Correspondent

WASHINGTON, May 2 (UPI) -- Vigorous efforts are under way to increase racial and ethnic diversity in clinical trials, but more needs to be done, researchers and advocates say.

"We need to know the right dose and side effects (of drugs) for these patients," said Howard McLeod, director of the Institute for Pharmacogenomics and Individualized Therapy at the University of North Carolina at Chapel Hill.


"The only way to know is to plan studies to answer those questions," McLeod told United Press International.

A growing body of evidence suggests race and ethnicity are sometimes key factors in predicting how patients will respond to a drug. Some drugs tend to function better for patients in certain groups, while other treatments are ineffective or even harmful in specific subpopulations.

As a prospective drug is tested for safety and efficacy, those positive or negative effects can only be detected if enough trial participants are drawn from a spectrum of racial and ethnic groups.


But trials rely largely on volunteer participants, and the average volunteer is a white male between 18 and 40 years old. The number of female and non-white participants -- often low -- becomes largely a matter of chance.

If race or ethnicity appears to be a factor in the drug's effects, researchers are forced to try to piece together information with data from the limited number of non-white patients in the study. If side effects or other problems are rare, or the number of non-white participants particularly small, no statistically significant conclusions can be drawn.

Some researchers have even had to repeat trials to investigate such effects. For example, the world's first phase 3 trial of an AIDS vaccine produced inconclusive results because of a lack of non-white participants, and further research was required. More often, the effects are undetected or not understood in detail.

Efforts to correct the problem range from consumer education to a dramatic redesign of the way trial subjects are recruited, but daunting barriers to clinical trial diversity remain.

"There are so many researchers and drug companies facing shortages of minority volunteers," said Diane Simmons, president and chief executive officer of the Center for Information & Study on Clinical Research Participation, a group that is partially supported by pharmaceutical companies and researcher groups.


As a result, "some advances in medicine are not happening on behalf of all folks," she told UPI.

The number of individuals of all races wanting to participate in clinical trials is very low, said Simmons, whose organization sponsors educational events in cities across the United States designed to inform the public about clinical trials.

Potential trial subjects often have deep concerns about the safety of trials and how much work they will require, she said. For members of the African-American community, that natural wariness can be compounded by the history of abuse of African-Americans in clinical trials. The infamous Tuskegee Syphilis Experiment, for example, denied poor black sharecroppers treatment for their syphilis in order to study the disease's progression.

"Rebuilding trust for the medical community is an important step," Simmons said.

Pharmaceutical giant Eli Lilly said it is launching a trial specifically recruiting subjects based on their ethnicity.

The company will be testing an anti-lung-cancer agent in a phase 3 trial with 200 African-American participants, and an equal number of Asian- and Hispanic-Americans and white subjects.

"Typically in a treatment study, you have some ethnic minority patients represented, but not enough to know if (that) group is a factor in how the treatment affects them," said Edward Stepanski, vice president of scientific affairs at Accelerated Community Oncology Research Group, which is managing the study.


The study is expected to be completed in two years, but recruiting those minority volunteers could be a challenge, Stepanski told UPI.

"We think this study is of great significance," he said. "We don't see a lot of these studies being done.

"It takes a major effort."

Instead of drawing volunteers to trials, it may be better to bring trials to patients, McLeod of the University of North Carolina said.

Moving trial sites to Asia and Africa, as some researchers have done, still leaves distinct populations like African- and Hispanic-Americans underrepresented, he said. Instead, resources should be invested to create research infrastructure in states like Mississippi or Tennessee where there are large minority communities but where little research takes place.

"It may need to not be Seattle and New York all the time," he said. "We're not doing our nation any favors."

The best long-term solution, however, will be the development of personalized medicine, McLeod said. Race is used as an imperfect proxy for the specific genetic characteristics of each individual. Once medical advances allow us to identify the specific genetic traits of an individual that make a drug more or less likely to work, the idea of race can be cast off altogether.


"Race is a means to an end," McLeod said.

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