The Importance of Age Diversity in Clinical Trials

It is often the case that elderly subjects are omitted from clinical trials. Consequently, physicians know very little about how a given treatment may affect their older patients. Is a medication effective for the elderly? Is it safe?  Without data, how is a physician to know?

Although there is an industry trend toward increased patient centricity and trial diversity, expanding trials to include older patients poses a challenge for research teams because it brings two tenets of quality research into conflict with one another-representative study populations and patient safety.  

The fundamental assumption of clinical research is that we can take data from a relatively small, representative selection of subjects and generalize the results to the larger patient population. If our sample is too constrained or poorly selected, we hinder the broad applicability of our results. This is not merely a statistical concern, but an ethical one. Unfortunately, our industry has long struggled with underrepresentation of important demographic groups, especially women, racial and ethnic minorities, and the elderly. 

At the same time, researchers are keenly concerned about protecting subject safety in trials. 

There is broad reluctance to conduct trials in what we deem “vulnerable populations,” namely children, cognitively impaired, pregnant women, and the elderly. The risk of doing more harm than good in these patient groups often leads us to play it safe and exclude these populations from trials. No case illuminates the challenging catch-22 we face like the awful thalidomide debacle of the 1950s-60s. Thalidomide, which was widely regarded as safe, was prescribed off-label for pregnant women to treat morning sickness. Tragically, the drug was later linked to severe birth defects and banned for expecting mothers.

On one hand, the physicians prescribing thalidomide did so based on limited knowledge of the drug’s safety in pregnant women. Had a trial had been conducted that demonstrated the risk to children, they would clearly know not to prescribe it to expecting mothers. Yet, the very risk of such dangerous complications is why such trials are not conducted in vulnerable populations in the first place. Risks for the elderly are different than for pregnant women, but the principal of protecting sensitive populations is the same.  

So, how do we negotiate this apparent impasse? A recent New York Times article, The Clinical Trial is Open. The Elderly Need Not Apply., by Paula Span offers a few general suggestions for increased inclusion, including restructuring studies and authorizing the FDA to require and incentivize the inclusion of older adults. Changing the laws and enforcement can certainly drive change, but what can we do in the near term, short of legislative intervention?  

A few additional suggestions:

• Reconsider age limits and avoid an all-or-none mentality to enrolling geriatric subjects. Instead, consider evaluating eligibility on a subject-by-subject basis, which will still allow exclusion of patients deemed too frail, risky, or comorbid for the trial.  

• Actively recruit older subjects. The lack of geriatric patients in our trials is a result of many years of both passively and actively excluding them, so effort is needed to reverse these trends. Beyond recruitment for an individual trial, researchers and providers should seek to educate older adults about clinical research.   

• Learn from other efforts to recruit marginalized populations. Improving trial diversity starts with an effort to thoroughly understand your patient population and their needs and reduce obstacles to their participation.  

• Engage patient advocacy groups that focus on elderly patients. Ask how trials can be better designed to meet their needs and include them. Partner with these groups to aid in information sharing and outreach.

• Learn what is already expected from agencies like the FDA and NIH when it comes to inclusivity.
• A recent NIH policy revision (stemming from the 21st Century Cures Act) will require new NIH grantees to have a plan for including children and older adults in their research.

• In 2012, the Food and Drug Administration Safety and Innovation Act (FDASIA) required the FDA to create an action plan to improve data quality and completeness for demographic subgroups (sex, age, race, and ethnicity) in applications for medical products.

• Design studies to examine effectiveness (demonstrating that a treatment produces desired results in ‘real world’ circumstances) not just efficacy (demonstrating that a treatment produces desired results in ideal conditions). 

Age diversity in clinical trials benefits both the patient experience and the success of the trial. The goal of clinical research is to develop treatments that help patients and gain FDA approval. Researchers need not shy away from including diverse patient populations, but they may need to revise their recruitment and retention strategies to be more inclusive, accommodating, and protective of those that are more vulnerable. With the FDA paying close attention to age diversity in clinical trials, it makes good business sense to study a drug within all of the patient populations that may need it.

Ryan Bailey, Senior Clinical Researcher, Rho, Inc.