1 in 5 MS Patients Don’t Adhere to Daily Oral DMTs, Real-world Study Finds

About 20%, or 1 in 5, multiple sclerosis (MS) patients fail to adhere to oral disease-modifying therapies (DMTs) taken each day, and about 1 in 4 stop using a prescribed daily oral treatment within one year, a study based on reported real-world use found.

The study “Real-world adherence to, and persistence with, once- and twice-daily oral disease-modifying drugs in patients with multiple sclerosis: a systematic review and meta-analysis” was published in the journal BMC Neurology.

Current guidelines recommend DMDs for people diagnosed with relapsing forms of MS, including relapsing-remitting MS and active secondary progressive disease. These medications have been shown to lower relapses rate, slow MS progression, and improve outcomes in the long term. Monitoring of adherence to these prescribed medications, adverse events, and tolerability is recommended.

Poor adherence to DMTs and their discontinuation are linked to worse clinical outcomes, higher rates of relapse and disease progression, and greater use of medical resources.

Oral DMTs are thought to improve adherence to treatment, because they are thought to be easier for patients to use than injectable treatments. However, several recent real-world studies suggest that adherence and persistence to once or twice daily oral DMTs — such as Gilenya (fingolimod, by Novartis), Tecfidera (dimethyl fumarate, by Biogen), and Aubagio (teriflunomide, by Sanofi Genzyme) — is actually similar to self-injectable therapies.

Researchers conducted a systematic review of real-world studies to assess the extent of non-adherence to oral DMTs by MS patients, searching for oral DMTs approved between January 2010 and April 2018.

Of note, two of its six researchers are employees of EMD Serono (known as Merck KGaA outside North America), which markets the MS injectable therapy Rebif (interferon beta-1a), and the oral short-course treatment Mavenclad (cladribine tablets; approved in early 2019).

From an initial 510 selected studies, 31 studies were analyzed, covering 16,398 MS patients treated daily with oral DMTs.

Most of these studies (18) were conducted in the U.S., followed by Europe (eight). Twelve studies (38.7%) were retrospective analysis of electronic medical records, eight (25.8%) were analyses of administrative claims databases, seven (22.6%) were prospective observational group studies, three (9.7%) used patient registries, and one (3.2%) was a patient survey.

Patients were followed in these studies between three months and three years, but more than half (67.7%) reported data at one year of follow-up. In 20 studies, the discontinuation rate for oral DMDs after one year ranged between 5.1% and 42.3%.

Two measures — called medication possession ratio (MPR) and the proportion of days covered (PDC) — were used to assess adherence to treatment. MPR is calculated as the total number of days between the first prescription and the last prescription, divided by the total days of the follow-up. PDC corresponds to the number of days in which a medication is available to a person (“covered” days) divided by the duration of the follow-up period.

Data from four studies reporting at one year of follow-up showed that the overall mean adherence to oral DMTs (taken once or twice a day) was 83.3%, while the overall mean PDC for the same period was 76.5%.

An MPR showing at least 80% adherence over one year was 78.5% across six studies, meaning that about 20% of the patients followed that year (1 in 5) failed to adhere to medication. During this period, a PDC of at least 80% was reported in 71.8%.

Pooled data from studies with one-year of follow-up found a discontinuation rate of 25.4% for oral maintenance DMTs, equivalent to 1 in 4 patients stopping the treatment.

“This meta-analysis of real-world studies showed that approximately one in five patients with MS do not adhere to once- or twice-daily oral maintenance DMD [disease-modifying drug] treatment regimens, and one in four patients with MS discontinue once- or twice-daily oral maintenance DMDs before 1 year,” the researchers wrote.

Such a finding is important because, they noted, that “adherence to newly initiated DMDs (oral or injectable) over 1 year among patients in the US” — compared with non-adherence “was associated with a decrease of 42% in the likelihood of relapse, 38% in emergency visits, and 52% in hospitalizations, as well as an average of 0.7 fewer outpatient visits annually

No significant differences were found for treatment discontinuation rates in the U.S. and other countries — 25.6% in U.S. vs. 25.3% in others. The largest proportions of patients discontinuing DMTs were found in administrative claims databases (29%).

“Opportunities to improve adherence and ultimately patient outcomes, such as patient education, medication support/reminders, simplified dosing regimens, and reducing administration or monitoring requirements, remain,” the researchers concluded.

“Implementation of efforts to improve adherence are essential to improving care of patients with MS.”