Objective: In relapsing-remitting multiple sclerosis (RRMS), suboptimal adherence to injectable disease-modifying therapies (iDMTs; interferon β-1a/b, glatiramer acetate) is common, reducing their effectiveness. Patient retention on oral fingolimod and iDMTs was evaluated in PREFERMS, a randomized, parallel-group, active-controlled, open-label, 48-week study.
Methods: Patients were included if they had RRMS, were aged 18-65 years and had Expanded Disability Status Scale score up to 6, enrolled at 117 US study sites, were treatment naïve or had received only one iDMT class. Patients were randomized 1:1 (fingolimod 0.5 mg/day; preselected iDMT) by interactive voice-and-web-response system without blinding, followed up quarterly, and allowed one study-approved treatment switch after 12 weeks, or earlier for efficacy or safety reasons. The primary outcome was patient retention on randomized treatment over 48 weeks. Secondary endpoints included patient-reported outcomes, brain volume loss (BVL), and cognitive function.
Results: Analysis of 433/436 patients receiving fingolimod and 428/439 receiving iDMTs showed that patient retention rate was significantly higher with fingolimod than with iDMTs [352 (81.3%) versus 125 (29.2%); 95% confidence interval 46.4-57.8%; p < 0.0001]. The most common treatment switch was from iDMT to fingolimod for injection-related reasons. Patient satisfaction was greater and BVL less with fingolimod than with iDMTs, with no difference in cognitive function. Adverse events were consistent with established tolerability profiles for each treatment.
Conclusions: In RRMS, fingolimod was associated with better treatment retention, patient satisfaction and BVL outcomes than iDMTs. Patients may persist with iDMTs, but many may switch treatment if permitted. Treatment satisfaction fosters adherence, a prerequisite for optimal outcomes.
Keywords: adherence; disease-modifying therapy; fingolimod; glatiramer acetate; interferon; multiple sclerosis; randomized controlled trial; retention.