Starting MS Treatment with Mild-to-Moderate Efficacy DMT More Likely to Result in Switch to High-Efficacy DMT

Multiple sclerosis (MS) is characterized by lesion formation along the central nervous system that can lead to symptom flare-ups (relapses). The disease progresses at variable speeds and can affect cognitive and motor function as well as various body systems, such as the gastrointestinal and urinary tracts. Disease-modifying therapies (DMTs) are designed to reduce relapses and new lesion formation and slow diseased progression.

The number of DMTs available to manage MS is vast. They are broadly divided into mild-to-moderate efficacy DMTs and high-efficacy DMTs. Mild-to-moderate efficacy DMTs are generally older drugs that may have lower potency but fewer side effects. High-efficacy DMTs are typically newer monoclonal antibodies that tend to be more potent but are associated with higher safety risks and costs.

Common treatment plans for MS involve using a step-therapy approach in which patients start treatment with a mild-to-moderate efficacy DMT and later switch to a high-efficacy DMT as the disease progresses. Some evidence suggests that starting MS treatment with a high-efficacy DMT may minimize relapses and delay long-term disability accumulation.

A group of researchers led by Niklas Frahm from the German MS Registry conducted a real-world registry study to compare the characteristics of patients with MS who switched from their first DMT with those of patients who continued taking their first DMT. The study results were published recently in Therapeutic Advances in Neurological Disorders.

Frahm and his colleagues used data from the German MS Registry to identify 2,722 patients who started DMT treatment between 2014 and 2021. A total of 1,361 patients who discontinued their first DMT treatment were matched by age and sex, with 1,361 patients who did not switch treatment.

Over half of the switchers (55.5%) changed their therapy within 1.5 years of treatment initiation. The first DMT for most patients (77.1%) was the mild-to-moderate efficacy treatment glatiramer acetate. More patients who switched DMTs changed to a high-efficacy DMT than to another mild-to-moderate efficacy DMT (36.6% versus 35.9%)

The most common reasons for switching from the first DMT were disease activity despite DMT (63.1%), followed by side effects (17.1%) and patient request (8.3%). The most common second DMTs were Gilenya (fingolimod) and Ocrevus (ocrelizumab).

The three strongest predictors for switching from the first DMT were beginning treatment with a mild-to-moderate efficacy DMT, starting the first DMT between 2014 and 2017, and spending a shorter period on the first DMT.

The authors conclude that most people with MS started treatment with a mild-to-moderate efficacy DMT, and disease activity is the most common reason for switching DMTs. This highlights that DMT switching is led by inadequate disease control. They propose that longer treatment strategy studies are necessary to investigate the initial use of high-efficacy DMTs in people with MS.