African-American patients with MS on fingolimod were 50.2% more likely to remain true to their treatment regimen than those treated with injectable disease-modifying therapies.
Mark Cascione, MD
A new subgroup analysis from a phase IV trial of fingolimod (Gilenya, Novartis) has revealed that the multiple sclerosis (MS) therapy is associated with better treatment adherence with African-American patients.
In the trial, African-American patients with MS that were given the oral fingolimod 0.5 mg/day were more 50.2% more likely to remain true to their treatment regimen than those who were treated with injectable disease-modifying therapies (DMTs).1
Led by Mark Cascione, MD, a neurologist with Tampa Neurology Associates in Florida, the full phase IV PREFERMS study explored the treatment retention of fingolimod in comparison with first-line DMTs in adult patients with relapsing-remitting MS (RRMS). The trial included 48-week data in comparison with 2 injectable DMTs: interferon ß-1a/b and glatiramer acetate.
In total, the multicenter trial randomized 875 patients to fingolimod or an injectable DMT, of which 16.1% (n = 141) were African-American. In analyzing the data, Cascione and colleagues found that among those receiving fingolimod, the retention rate over the course of 48 weeks was 80.6% (n = 54 of 67) compared with 30.4% (n = 21 of 69) of those administered injectable DMTs for a difference of more than 50% (95% CI, 35.8 to 64.6; P <.0001).
This finding was consistent with the findings of the full study cohort, which found that 81.3% of patients given fingolimod were retained compared to 29.2% of those on injectable DMTs (P <.0001).2
Cascione and colleagues conducted a sensitivity analysis to determine if the treatment history of patients impacted the retention rates but found it consistent with the overall analysis. Those who were treatment-naïve had retention rates of 80.6% (n = 29 of 36) of those on fingolimod compared to 30.3% (n = 10 of 33) of those on injectable therapy, for a group difference of 50.3% (95% CI, 29.9 to 70.6; P <.0001). Similarly, among patients who had previously been treated and received fingolimod (n = 31), retention rates were 80.6%, compared to 30.6% (n = 11) for the patients on other therapy (n = 36), totaling a difference of 50% (95% CI, 29.6 to 70.6; P <.0001).
This finding is promising, as less than optimal adherence to injectable DMTs is common among patients with MS, and in turn, reduces treatment efficacy. This is especially true among African-Americans, who, as Cascione and colleagues noted, “may experience a more aggressive disease course than Caucasian patients, with a greater risk of developing ambulatory difficulties and other disabilities and may also have a diminished response to some disease-modifying therapies compared with patients of other ethnicities.”
The assessment also featured a treatment satisfaction outcome, as measured by the Medication Satisfaction Questionnaire (MSQ). The results revealed that 80.6% (n = 54) of patients treated with fingolimod expressed satisfaction—either ‘somewhat’, ‘very’, or ‘extremely’ so—compared to 49.3% (n = 34) of those treated with an injectable therapy (difference, 31.3%; 95% CI, 16.2 to 46.5; P <.0001). These were also consistent with the overall findings of the PREFERMS study.
Among the African-American patients who discontinued injectable DMTs, those who switched to fingolimod were significantly more likely to express treatment satisfaction after switching. All told, 73.5% expressed satisfaction in the randomized treatment phase, while 92.7% did so during the switched-treatment phase (odds ratio [OR], 5.5; 95% CI, 1.3 to 22.9; P = .0178). Among the 3 (6.7%) patients who discontinued fingolimod, satisfaction decreased after switching to injectable DMT. According to the authors, 1 patient who switched between injectable DMTs displayed increased satisfaction.
In terms of discontinuation, 18.8% (n = 13) patients on fingolimod withdrew from the study, in comparison with 27.8% (n = 10) in the DMT group. The main reason for discontinuation was withdrawn consent in the fingolimod group (n = 4) and adverse events (AEs) in the DMT group (n = 7).
During the randomized phase, 86.6% (n = 58) of fingolimod patients reported ≥1 AE in comparison with 78.3% (n = 54) in the DMT arm. The most common AEs reported with fingolimod were arthralgia, nasopharyngitis, and fatigue (rates per patient-year of 0.115, 0.114, and 0.114, respectively). In patients receiving DMTs, the most common AEs were injection-site reaction, injection-site pain, and influenza-like illness (rates per patient-year of 0.301, 0.291, and 0.290, respectively). “The large difference in treatment retention rate between the fingolimod and DMT groups meant that patient exposure to fingolimod was greater than that to DMTs in the randomized phase. To allow for this difference, data for AEs were adjusted for treatment exposure and reported as rates per patient-year,” the authors noted.
1. Cascione M, Tenenbaum N, Wendt J, et al. Treatment retention on fingolimod compared with injectable multiple sclerosis therapies in African-American patients: A subgroup analysis of a randomized phase 4 study. Mult Scler Relat Dis. 2018;25(1):50-56.
2. Cree BA, Arnold DL, Cascione M, Fox EJ, et al. Randomized phase 4 study of retention on fingolimod vs injectable multiple sclerosis therapies. Ther Adv Neuro. Disord. 2017;11:1-15.