Multiple Sclerosis, Relapsing-Remitting
Conditions
Keywords
Natalizumab, Extended Interval Dosing
Brief summary
Natalizumab (NTZ) use in Multiple Sclerosis (MS) in highly active patients has been largely established during the last Rationale 10 years in both clinical trials and real-world practice. Along with its efficacy, NTZ use has been limited by potential risk of progressive multifocal leukoencephalopathy (PML). Thus, several studies have tried to assess how to minimize this risk. One suggested approach is to move from the standard interval dose (SID) of 4 weeks to an extended interval dose (EID) of 5 weeks or longer. Extending the dosing interval of NTZ has been practiced by some physicians with the intention of improving the benefit/risk of the treatment by reducing the exposure-dependent risk of progressive multifocal leukoencephalopathy (PML) while maintaining efficacy. We propose to retrospectively analyze data from clinical records coming from RRMS patients treated in France at 5 different centers; Caen, Nice, Bobigny and Toulouse hospitals as well as Percy Military Hospital, to evaluate the effectiveness of natalizumab EID in subjects who have previously been treated with natalizumab SID for 12 months, in relation to continued SID treatment. In the clinical practice of these centers, patients are shifted after minimum 12 months under SID to an EID of 6 weeks regardless antibody JC serum status. Clinical, magnetic resonance imaging (MRI) and serum anti-JCV antibody status data are collected when available. The objective of this study is to assess the efficacy in term of ARR and safety.
Interventions
DRUGNatalizumab Injection [Tysabri]
Natalizumab infusion interval according to local practice defining the patient's group
Sponsors
Biogen
University Hospital, Caen
Study design
Observational model
CASE_CONTROL
Time perspective
RETROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patients receiving at least 11 infusions of natalizumab as disease-modifying monotherapy for RRMS that is consistent with the approved dosing
Exclusion criteria
* Patients for whom the NTZ infusion history and/or MRI and clinical history is not available. * Patients with dosing gap defined as \>=12 weeks between any two doses. * Patients with over dose defined as \<3 weeks between any two doses. * Pregnancy during the follow-up period
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Annualized Relapse Ratio | baseline to 12 month follow-up | relapse rate per patient per year |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Disability progression | baseline to 12 month follow-up | Increase in EDSS score during the follow-up period |
| NEDA-3 achievement | baseline to 12 month follow-up | Estimation of the proportion of patients achieving NEDA-3 criteria at the end of the follow-up period |
| Radiological activity | baseline to 12 month follow-up | Detection of increase MRI activity defined as new or enlarged T2 lesions and/or new gadolinium enhancing lesions |
Other
| Measure | Time frame | Description |
|---|---|---|
| Safety outcome | baseline to 12 month follow-up | Description of PML cases and variations in anti-JCV antibody status when available |
Countries
France
Outcome results
None listed