Baclofen Discontinuation Rates for MS Spasticity Indicate Need for Alternatives

Despite high rates of treatment discontinuation, younger patients with incident and prevalent multiple sclerosis (MS) received treatment with baclofen more often for spasticity than older patients, according to a Swedish large, population-based study published in the Journal of Neurology, Neurosurgery, & Psychiatry.

Spasticity is one of the common symptoms in MS. However, there is limited research that describes spasticity treatment patterns. Baclofen is the first-line option for managing spasticity in MS in Sweden. In an effort to better understand treatment patterns with baclofen, Swedish researchers assessed the associations with spasticity treatment via oral baclofen use among patients with MS.

They conducted a longitudinal cohort study from July 1, 2005 to December 31, 2014 of 1826 and 3519 individuals with incident and prevalent MS, respectively. The researchers analyzed trends in MS treatments for spasticity using data obtained from Swedish registers such as the Epidemiological Investigation of MS (EIMS), Genes and Environment in MS (GEMS), and Immunomodulation and MS Study (IMSE).

Approximately 10% of patients with incident MS and 19% of patients with prevalent MS received baclofen for spasticity. Those with incident MS often were prescribed baclofen within the first 6 months after diagnosis, while those with prevalent MS received this prescription within 3 years following diagnosis.

Younger patients between the ages of 18 and 44 years were 3 times more likely to receive baclofen treatment compared with patients aged 45 years and older, despite similar disability levels according to Expanded Disability Severity Scores (EDSS).

• EDSS scores of 3.0-5.0; hazard ratio [HR], 5.62; 95% CI, 2.91-10.85 in younger patients vs. HR, 2.05; 95% CI, 1.10-3.82 in older patients
• EDSS scores of 6+; HR, 15.41; 95% CI, 7.07-33.58 in younger patients vs. HR, 4.26; 95% CI, 1.96-9.17 in older patients

Discontinuation of baclofen was very high, occurring in 49% of patients with incident MS within the first 150 days of initiation and 90% within 2 years, including those with higher EDSS scores and more progressive courses of MS. Patients with prevalent MS demonstrated similar rates of discontinuation.

The researchers acknowledged that spasticity can occur earlier in patients with MS than previously believed. This can inform clinicians who help their patients manage MS symptoms.

“High rates of baclofen discontinuation highlight the need for more tolerable and efficacious spasticity treatments and monitoring of spasticity among people with MS.”

Study limitations included lack of information about spasticity severity, potential underestimation of spasticity, inability to analyze effects of disease-modifying therapies along with concomitant baclofen use.

Disclosures: Several study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see original source for full list of disclosures.