Background

Natalizumab extended interval dosing (EID) is associated with lower risk of progressive multifocal leukoencephalopathy than every-4-week standard interval dosing (SID). Independent real-world (RW) studies suggest that natalizumab effectiveness is maintained in patients who switch from SID to EID. MS PATHS (Multiple Sclerosis Partners Advancing Technology and Health Solutions) is a learning health system comprised of a collaborative network of healthcare institutions that provides access to RW clinical and MRI data collected using standardized acquisition protocols.

Objectives

Compare the effectiveness of natalizumab EID and SID using quantitative MRI metrics from highly standardized RW images in MS PATHS.

Methods

An MRI segment was defined as 2 MRI acquisitions and associated interval duration. MS PATHS patients with ≥1 MRI segment, ≥2 infusion cycles (infusion interval >21 days and ≤84 days), and complete covariate information were eligible. MRI segments with average infusion cycle (AIC) ≤35 days and >35 days were defined as SID and EID, respectively. For each MRI segment, new T2 lesions and changes in T2 lesion volume (T2LV) and brain parenchymal fraction (BPF) were compared for SID and EID using inverse probability weighting (IPW) with logistic regression and robust linear regression.

Results

IPW analysis included 327 SID patients (596 MRI segments) and 67 EID patients (85 MRI segments). The mean AIC for SID was 29.5 (standard deviation [SD] 1.8) days and 40.8 (4.9) days for EID. Mean MRI segment duration for SID and EID was 9.7 (SD 5.5) and 9.6 (5.3) months, respectively. Proportions of patients with no new T2 lesions were similar for the SID and EID groups (75.6% vs 75.3%; adjusted odds ratio for 0 vs ≥1 lesion=0.967 [95% CI 0.500, 1.871]; P=0.921). SID and EID patients did not differ significantly in adjusted T2LV change (−0.070 [95% CI −0.129, 0.111] mL vs 0.022 [−0.132, 0.180] mL; P=0.233) or BPF change (−0.1222% [95% CI −0.1524%, −0.0921%] vs −0.1442% [−0.2234%, −0.0649%]; P=0.617).

Conclusions

MRI activity was low in SID and EID MS PATHS patients, and there were no significant differences in MRI outcomes between the 2 groups. These results confirm and extend previous RW studies of natalizumab EID effectiveness. Study limitations include modest EID sample size and potential channeling bias. The ongoing phase 3b randomized trial NOVA (clinicaltrials.gov NCT03689972) will further evaluate the effectiveness of natalizumab EID versus SID.

MS PATHS is supported by Biogen.

Background

Natalizumab 300 mg every 4 weeks (Q4W) is an effective therapy for relapsing-remitting multiple sclerosis (MS) but is also associated with increased risk of progressive multifocal leukoencephalopathy (PML) in anti–JC virus seropositive patients. Analysis of the TOUCH Prescribing Program safety database showed that natalizumab extended interval dosing (EID; average dosing interval approximately 6 weeks) is associated with lower risk of PML than Q4W dosing. Previous analysis of TYSABRI Observational Program (TOP) data showed no difference in relapse outcomes for patients on Q4W and every-6-week (Q6W) dosing. Comparative disability outcome data in well-matched real-world populations are lacking.

Objectives

Compare relapse and disability outcomes in propensity-score (PS)–matched TOP patients who switched to Q6W dosing with outcomes in patients who remained on Q4W dosing.

Methods

Intentional dosing data collected in TOP as of November 2019 were used to identify patients with ≥1 year of Q4W dosing who remained on Q4W or switched to Q6W dosing. Patients with dosing intervals ≥12 weeks or <3 weeks were excluded. Patients with similar exposures were PS-matched 1:1 with age, sex, Expanded Disability Status Scale score, time from MS onset, exposure duration, and relapse activity as covariates. Between-group comparisons were made for the post-switch follow-up period for Q6W patients and the matching time period for Q4W patients. Adjusted relapse rates (ARRs) were calculated using negative binomial regression with robust standard error estimation. Hazard ratios (HRs) for time to first relapse and 24-week confirmed disability worsening (CDW) were estimated with Kaplan-Meier and Cox methods.

Results

The analysis included 236 matched pairs of Q6W and Q4W patients. Mean (SD) follow-up times for Q6W and Q4W patients were 2.00 (1.30) and 1.89 (1.15) years, respectively. ARRs (0.146 vs 0.139; P=0.796), time to first relapse (HR [95% CI] 1.078 [0.723–1.608]; P=0.711), and time to CDW (HR [95% CI] 0.749 [0.270–2.074]; P=0.578) did not differ significantly for Q6W and Q4W patients.

Conclusions

Relapse and disability outcomes in TOP were similar for PS-matched patients who switched to Q6W or remained on Q4W dosing. These results are consistent with prior matched and unmatched analyses in real-world settings and underscore the need for the ongoing, prospective, randomized efficacy trial of natalizumab Q6W vs Q4W dosing (NOVA, clinicaltrials.gov NCT03689972).

The TOP study was supported by Biogen.

Background

Magnetic resonance imaging (MRI) can supplement clinical diagnostic criteria for multiple sclerosis (MS) by increasing diagnostic sensitivity and predicting the onset of clinically definite MS (CDMS).

Objectives

To determine whether the number of gadolinium-enhanced (Gd⁺) lesions and T2 volume at baseline (BL) may be predictors of CDMS.

Methods

RENEW (NCT01721161) was a randomised, double-blind, placebo-controlled study of participants with a first episode of acute optic neuritis who were treated with opicinumab 100 mg/kg once every 4 weeks (6 doses) and followed-up to week 32. Eligible participants were enrolled in RENEWED (NCT02657915), a 1-day follow-up (Day 1) at 2 years, to study the long-term electrophysiologic and clinical outcomes of treatment with opicinumab vs. placebo. Severity of disease using brain MRI was a secondary efficacy endpoint. In a post hoc analysis of brain MRI lesions, the number of Gd⁺ lesions and volume of T2 lesions at BL in RENEW were assessed for predicting CDMS at Day 1 of RENEWED for the intention-to-treat (ITT) and per protocol (PP) populations. Primary analyses were performed in the PP population.

Results

The numbers of RENEW participants who completed RENEWED were 52/82 in the ITT population (opicinumab, n=28; placebo, n=24) and 47/69 in the PP population (opicinumab, n=24; placebo, n=23). In the PP population, 40/47 (85%) did not have CDMS prior to enrollment in RENEW; 24/40 at-risk participants (opicinumab n=12; placebo n=12) developed CDMS from enrollment in RENEW up to Day 1 in RENEWED. Median time to CDMS diagnosis after enrollment in RENEW was 909.5 days in the opicinumab group and 386.0 days in the placebo group. CDMS developed in participants with Gd⁺ lesions and enlarged T2 volumes at RENEW baseline. The hazard ratios (95% CI; p-value) of MRI measures at BL were: presence of Gd⁺ lesions, 11.52 (2.20, 60.25; p<0.001); number of Gd⁺ lesions, 6.78 (1.97, 23.35; p=0.0024); and T2 volume, 1.80 (1.34, 2.43; p=0.0001). Participants who did not develop CDMS had no Gd⁺ lesions at BL and had lower T2 volumes compared with participants who developed CDMS. Results were comparable in the ITT population. No differences were found in the risk of converting to CDMS in participants treated with opicinumab vs. placebo in either the ITT or PP populations.

Conclusions

The number of Gd⁺ lesions and T2 volume at BL may predict the onset of CDMS. A limitation of this study is its small sample size.

Supported by: Biogen