Efficacy and tolerability of natalizumab in relapsing–remitting multiple sclerosis patients: a post-marketing observational study

Abstract

To evaluate the efficacy and safety of natalizumab in patients with active relapsing-remitting multiple sclerosis (MS). We included 285 MS patients receiving natalizumab. Clinical, neuroradiological and safety data were registered every 6 months. Neutralizing antibodies (NABs) were tested after 6 months of treatment. After 1 year, the annualized relapse rate decreased to 0.26, with a significant reduction compared to the previous year (2.13). At 24 months the proportion of "relapse free" patients was 78% while that of "MRI free" patients was 69%. Considering clinical and MRI cumulative activity, "disease free" patients were 63% at 24 months. A total of 18 patients showed NABs positivity. We reported 34 cases of treatment interruptions. In conclusion, our data confirm the remarkable efficacy of natalizumab in a group of patients with higher disease activity than that of pivotal studies.

Multiple Sclerosis Treatment with Natalizumab: Analysis of a Hospital-Based Cohort

“…In general, our results fit those earlier reported in other post-marketing studies, regarding efficacy and safety. [5][6][7][8][9][10][11] Our data are also consistent with previous findings in terms of baseline patients' profile: age at NZ starting, ARR in the year prior to NZ and clinical MS form. [5][6][7][8][9][10][11] Exception for consistency with other previous findings is made for baseline EDSS and disease duration until NZ, both found to be higher in our study than others 'real-world' studies.…”

“…[5][6][7][8][9][10][11] Our data are also consistent with previous findings in terms of baseline patients' profile: age at NZ starting, ARR in the year prior to NZ and clinical MS form. [5][6][7][8][9][10][11] Exception for consistency with other previous findings is made for baseline EDSS and disease duration until NZ, both found to be higher in our study than others 'real-world' studies. [5][6][7][8][9][10][11] It's possible that patients were included too late in the disease evolution; it may be explained by some initial reluctance in NZ prescription, regarding safety concerns, namely PML.…”

“…[5][6][7][8][9][10][11] Exception for consistency with other previous findings is made for baseline EDSS and disease duration until NZ, both found to be higher in our study than others 'real-world' studies. [5][6][7][8][9][10][11] It's possible that patients were included too late in the disease evolution; it may be explained by some initial reluctance in NZ prescription, regarding safety concerns, namely PML. On the other hand, this may reflect initial expectations about a new treatment; in fact, when NZ was first licensed in Portugal, it was seen as a last 'hope' for some patients, who were later found to be in a progressive phase of disease.…”

From injection therapies to natalizumab: views on the treatment of multiple sclerosis

“…Following the development of a risk management strategy, the drug was reintroduced into the marketplace in June 2006. Since that time, the postmarketing experience has substantiated the impressive efficacy of natalizumab, but also confirmed the ability of this agent to increase the development of PML in a small percentage of patients [Sangalli et al 2011;Kappos et al 2011;Biogen Idec, 2011]. The dynamics of the JC virus infection, the host immune response (the presence of JC virus IgG appears to portend a higher risk of PML than patients who are seronegative), and the influence of antecedent treatments (e.g.…”

Effectiveness of Natalizumab in Patients with Highly Active Relapsing Remitting Multiple Sclerosis

“…A subsequent post-hoc analysis introduced the concept of freedom from disease and showed that 37% of patients included in the AFFIRM study remained free of both clinical activity and radiological activity at 2 years [3,4]. Since then, several post-marketing studies have confirmed the effectiveness of NTZ in daily clinical practice [5,6,7,8,9,10,11], although only a few have exclusively evaluated the effectiveness of NTZ in patients with highly active RRMS (HA-RRMS) [12,13]. …”