Research methods: Clinical trials in geriatric oncology

Abstract

For various reasons, older adults are underrepresented in cancer clinical trials. As the selection criteria in randomized controlled trials are well controlled, younger and fitter patients are usually only eligible, making it difficult for clinicians to draw conclusions on the effects of drugs in older, frail, or unfit adults. With an aging world population, more attention needs to be focused on geriatric oncology, but the challenge lies in designing trials that capture the heterogeneity of an entire population, particularly the elderly and frail. Separate trials for older patients are needed that incorporate more appropriate end points and suitable control arms. Pharmacokinetic studies should also be undertaken given the effect of aging organs on drug pharmacokinetics. How to design such trials in the absence of global standardized geriatric assessment tools and definitions is, however, challenging. Randomized or single-arm phase II trials in older adults can provide important information on efficacy and toxicity where a phase III randomized controlled trial (RCT) is not feasible. Observational cohort studies are proposed as an adjunct to RCTs. Large and well-designed observational cohort studies can capture relevant and clinically meaningful data in realworld settings on older patients ineligible for RCTs. Better clinical trial design is crucial to understanding the impact of new cancer therapies on older patients. Trials in older cancer patients should be compulsory.