The efficacy of MAYZENT was demonstrated in Study 1, a randomized, double-blind, parallel-group, placebo-controlled, time-to-event study in patients with secondary progressive multiple sclerosis (SPMS) who had evidence of disability progression in the prior 2 years, no evidence of relapse in 3 months prior to study enrollment, and an Expanded Disability Status Scale (EDSS) score of 3.0 to 6.5 at study entry (NCT 01665144).

Patients were randomized to receive either once daily MAYZENT 2 mg or placebo, beginning with a dose titration [see Dosage and Administration (2.2)]. Evaluations were performed at screening, every 3 months during the study, and at the time of a suspected relapse. MRI evaluations were performed at screening and every 12 months.

The primary endpoint of the study was the time to 3-month confirmed disability progression (CDP), defined as at least a 1-point increase from baseline in EDSS (0.5-point increase for patients with baseline EDSS of 5.5 or higher) sustained for 3 months. A prespecified hierarchical analysis consisted of the primary endpoint and 2 secondary endpoints, the time to 3-month confirmed worsening of at least 20% from baseline on the timed 25-foot walk test and the change from baseline in T2 lesion volume. Additional endpoints included annualized relapse rate (relapses/year) and MRI measures of inflammatory disease activity.

Study duration was variable for individual patients (median study duration was 21 months, range 1 day to 37 months).

Study 1 randomized 1651 patients to either MAYZENT 2 mg (N = 1105) or placebo (N = 546); 82% of MAYZENT-treated patients and 78% of placebo-treated patients completed the study. Median age was 49.0 years, 95% of patients were white, and 60% female. The median disease duration was 16.0 years, and median EDSS score at baseline was 6.0 (56% of patients had ≥ 6.0 EDSS at baseline); 36% of patients had one or more relapses in the 2 years prior to study entry; 22% of those patients with available imaging had one or more gadolinium-enhancing lesions on their baseline MRI scan; 78% of patients had been previously treated with an MS therapy.

Results are presented in Table 4. MAYZENT was superior to placebo in reducing the risk of confirmed disability progression, based on a time-to-event analysis (hazard ratio 0.79, p < 0.0134; see Figure 1). MAYZENT did not significantly delay the time to 20% deterioration in the timed 25-foot walk, compared to placebo. Patients treated with MAYZENT had a 55% relative reduction in annualized relapse rate, compared to patients on placebo (nominal p-value < 0.0001). The absolute reduction in the annualized relapse rate was 0.089. Although MAYZENT had a significant effect on disability progression compared to placebo in patients with active SPMS (e.g., SPMS patients with an MS relapse in the 2 years prior to the study), the effect of MAYZENT in patients with non-active SPMS was not statistically significant (see Figure 2).

Figure 1 Time to Confirmed Disability Progression Based on EDSS (Study 1)

Figure 2 Time to Confirmed Disability Progression Based on EDSS (Study 1), Subgroup Analysis

*HR and 95% CI presented are model-based estimates for a range of values of age and Expanded Disability Status Scale (EDSS).