Real World Effectiveness of Natalizumab Extended Interval Dosing in a French Cohort (RELEVANT)

Caen University Hospital

Status: Completed

Conditions: Multiple Sclerosis, Relapsing-Remitting

Treatments: Drug: Natalizumab Injection [Tysabri]

Study type: Observational

Funder types: Other; Industry

Identifiers

NCT04580381

FRA-TYS-19-11504

Details and patient eligibility

About

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.

Enrollment: 500 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

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

Trial design

500 participants in 2 patient groups

Standard Interval Dosing (SID)

Description:

Patients continuing Natalizumab treatment with standard interval dosing defined as \> 11 infusions per year

Treatment:

Drug: Natalizumab Injection [Tysabri]

Extended Interval Dosing (EID)

Description:

Patients switching to extended interval dosing defined as ≤ 10 infusions per year

Treatment:

Drug: Natalizumab Injection [Tysabri]