Practicing evidence-based medicine requires evidence, but the evidence for efficacy and safety of new and evolving cancer therapies in older adults is wanting due to their underrepresentation in oncology clinical trials. “It is difficult to practice evidence-based medicine in an older population because the data [aren’t] there,” according to Stuart M. Lichtman, MD, FACP, FASCO, a medical oncologist at Memorial Sloan-Kettering Cancer Center, Commack, New York; Professor of Medicine at Weill Cornell Medical College, New York; and President of the International Society of Geriatric Oncology (SIOG).

A recent analysis by the U.S. Food and Drug Administration of enrollment of older adults in oncology clinical trials found that during the period 2005 to 2015, the cancer incidence rate for patients older than age 65 was 56%, but the rate of participation in clinical trials was 40%.¹ Among the acknowledged barriers to participation by older adults in clinical trials are physician bias and patient attitudes and overall health.

Overcoming Physician Barriers

A 2014 article in the Journal of Clinical Oncology reported that most older people have a positive attitude toward oncology clinical trials and would be willing to participate, but “physician bias can be one of the main barriers to the enrollment of older patients.”² That same year, accepting the B.J. Kennedy Award for Scientific Excellence in Geriatric Oncology, Dr. Lichtman said the barriers “are us—physicians—to a large extent” and stressed “physician education is really the key.”³

Since then, ASCO, SIOG, and the European Society for Medical Oncology (ESMO) have developed physician education tools that are available on line, Dr. Lichtman noted. “How much they are utilized, I am never quite sure, but they are available and not difficult to obtain.”

Patient Barriers to Clinical Trials

Physicians may be reluctant to recommend clinical trials to older adults out of concern for patients’ overall health and comorbidities, and patients themselves may be put off by having to travel, sometimes long distances, to cancer centers and overnight stays. “Travel and caregiver issues are always concerns,” Dr. Lichtman said, but trials with immunotherapy agents with reduced toxicities are “encouraging” and making it more likely that older patients will be able to tolerate treatment.

Increased news coverage of clinical trials has led to greater awareness of and what it means to participate in a clinical trial. Physicians should help patients interpret issues concerning potential risks and benefits and “explain how a trial either is appropriate or inappropriate for their particular situation,” Dr. Lichtman advised. Patient information about clinical trials, including benefits, risks, and questions to ask before enrolling in a trial, is available online from the National Institute on Aging.⁴

“Placebo and randomized trials are always difficult,” Dr. Lichtman said. “Older people are willing to go on a study if you present it as appropriate for them. If they are overly concerned about side effects or don’t want to be randomized, then obviously they shouldn’t participate.” ■

DISCLOSURE: Dr. Lichtman reported no conflicts of interest.

References

1. Singh H, Kanapuru B, Smith C, et al: FDA analysis of enrollment of older adults in clinical trials for cancer drug registration: A 10-year experience by the US Food and Drug Administration. 2017 ASCO Annual Meeting. Abstract 10009. Presented June 5, 2017.

2. Hurria A, Dale W, Mooney M, et al: Designing therapeutic clinical trials for older and frail adults with cancer: U13 conference recommendations. J Clin Oncol 32:2587-2594, 2014.

3. Bath C: ‘Physician education is key’ to continued advances in geriatric oncology. The ASCO Post. July 10, 2014.

4. National Institute on Aging: Why do clinical trials need older and diverse participants? Available at https://www.nia.nih.gov/health/why-do-clinical-trials-need-older-and-diverse-participants. Accessed July 25, 2017.