WEST PALM BEACH, FLA. –
MS disease activity typically declines with age. At the same time, evidence to support the efficacy of MS drugs in older patients is limited, said Yinan Zhang, MD, a researcher at Icahn School of Medicine at Mount Sinai, New York. Clinical trials have tended to enroll younger patients and to include only patients with active disease, which is not representative of most older patients in the real world, Dr. Zhang said.
“DMTs for MS may be less efficacious in the elderly, especially in the absence of active disease, yet real-world prescribing patterns still show widespread use of DMTs in older patients,” Dr. Zhang and colleagues said. Physicians may be able to use the presence of disease activity to identify older patients who should receive therapy. “Continuing DMTs in elderly patients who have no evidence of disease activity should be questioned rather than accepted,” they said at the meeting held by the Americas Committee for Treatment and Research in Multiple Sclerosis.
To investigate whether age affects the efficacy of DMTs in patients with relapsing-remitting MS and how often DMTs are used in different age groups, Dr. Zhang and coinvestigators conducted a meta-analysis of group-level data from clinical trial, analyzed individual-level data from one of the trials, and reviewed survey data from two registries.
The meta-analysis included 26 clinical trials of 13 DMTs with more than 12,400 patients. Participants had an average age of about 37 years. “An age-dependent relationship of DMTs on relapse rate in RRMS [relapsing-remitting MS] cannot be established with currently published aggregate summary data,” the researchers said. “The meta-analysis was limited by the use of group-level data resulting in a narrow range of mean age.”
In an effort to overcome the limitations of group-level data, they analyzed individual-level data from approximately 1,000 patients in the CombiRx trial, which compared interferon beta-1a plus glatiramer acetate versus the agents alone. Thirty-seven of the patients were aged 55 years or older. The results suggest that each “1-year increase in baseline age was associated with a 3.2% reduction in the odds of having a relapse” during the trial, the investigators said. Change in annualized relapse rate was not significantly associated with age group, which may have resulted from “enrollment criteria selecting for patients with active disease, where DMTs are expected to show the greatest efficacy,” the researchers said.
Finally, Dr. Zhang and colleagues reviewed data on DMT use by age group from the North American Research Committee on Multiple Sclerosis (NARCOMS) and the Multiple Sclerosis Surveillance Registry (MSSR) from Veterans Affairs. In a 2018 survey of nearly 7,000 patients in the NARCOMS registry, 39.2% of patients older than 60 years were taking a DMT, including 44.5% of patients aged 61-70, 28.6% of patients aged 71-80, and 11% of patients aged 81 years and older. In comparison, about 62% of patients aged 41-50 years were taking DMT.
A 2019 survey of about 1,700 veterans in the MSSR found that 36.3% of patients older than 60 years were taking a DMT, including 41.1% of patients aged 61-70, 27.2% of patients aged 71-80, and 7.1% of patients aged 81 years and older. Among patients aged 41-50 years, more than 72% were taking a DMT. “The continued use of DMTs in the elderly may be the result of the perceived notion that disease inactivity is due to the effect of DMTs rather than the natural disease course with aging,” they said.
Dr. Zhang had no relevant disclosures. Coauthors disclosed consulting for and grant support from various pharmaceutical companies.
SOURCE: Zhang Y et al. ACTRIMS Forum 2020. Abstract P263.