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Why are Older Adults Underrepresented in COVID Vaccine Clinical Trials?

Jul 21, 2020 by CenTrial

Excluding the elderly from COVID vaccine trials

Older adults are the most adversely affected by COVID with 8 out of 10 COVID deaths occurring in those over the age of 65, so why are they so underrepresented in COVID-19 vaccine clinical trials?

A preliminary study by the Harvard Medical School found that 15% of COVID-19 trials systematically exclude adults aged 65 and older. This oversight could lead to inaccurate data, making it even harder to create a vaccine that is effective for older adults who are already in the highest risk group.

Another 12% of trials excluded older adults by using exclusion criteria that eliminates those with health conditions such as diabetes and hypertension, which disproportionally affect the elderly.

"With vaccine research, if we only test a vaccine in a younger population, we run the risk of having a vaccine that doesn't work on older adults," says Marina Martin, assistant professor and section chief of Geriatric Medicine at Stanford Medicine. "And then, the most vulnerable population will still be at an increased risk and will remain a group in which the virus can thrive and proliferate."

Ageism is not limited to just the COVID vaccine trials and can be found in other clinical trials as well. As more and more people in their 80s and 90s are functional and on minimal medications, researchers need to redesign trial studies to make them more elderly-friendly.

Researchers may find it more convenient and get quicker results by studying younger patients, but the downside is that trial results are less inclusive, and therefore less effective for the excluded groups.

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