There is limited evidence on the effects of disease modifying therapies (DMTs) on MS symptoms, health-related quality of life (HRQoL) and employment outcomes, particularly the comparative effectiveness between different available DMTs.
By using the prospectively collected patient-reported data in the Australian MS Longitudinal Study (AMSLS) from 2015 to 2017, we aimed to compare natalizumab to other DMTs in relation to employment outcomes, MS symptom severity, HRQoL, and progression in the previous 12 months.
Medication and Disease Course surveys were conducted in 2015, 2016 and 2017, and collected data on DMTs, severity of 13 MS symptoms (0-10 scale), disability, HRQoL by European Quality of Life with five dimensions (EQ-5D) and work productivity loss (absenteeism, presenteeism, total work productivity loss in the previous 4 weeks). We used marginal structural models to estimate causal effect of natalizumab versus other DMT comparators (any other DMT, classic injectables, oral therapies (teriflunomide and dimethyl fumarate), higher efficacy DMTs (fingolimod, alemtuzumab and mitoxantrone), fingolimod, and alemtuzumab), while adjusting for time-varying confounders and intermediates of treatment effects.
The analysis included 2836 observations. Compared to any other DMTs, natalizumab was associated with superior effects over time on improving balance, vision symptoms, sensory symptoms, bladder symptoms, sexual dysfunction, and feelings of anxiety. The strongest effect was seen for improving sensory problems (mean coefficient -0.44 (-0.66 to -0.22) per year). There was no evidence of an effect of natalizumab over time on improving HRQoL measured by the EQ-5D, but use of any other DMTs were associated with a significant decrease in EQ-5D. The use of natalizumab was associated with a marginal decrease in self-reported progression in the previous 12 months while the use of injectable DMTs and fingolimod were associated with an increased self-reported progression. The use of natalizumab was associated with a reduction in work productivity loss due to absenteeism compared to a worsening for any other DMT, and similar trends were less pronounced for presenteeism and total work productivity loss.
Compared to other DMTs, the use of natalizumab was associated with superior effects over time for several MS symptoms and absenteeism.