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Natalizumab-PML survivors with subsequent MS treatment: Clinico-radiologic outcome
Elisabeth Maillart1, Jean-Sebastien Vidal1, David Brassat1
1Department of Neurology (E.M., C. Louapre, C. Lubetzki, C.P.), Pitié-Salpêtrière Hospital, APHP, Paris; Department of Gerontology (J.-S.V.), Broca Hospital, APHP, Paris; Department of Neurology (D.B.), University Hospital of Toulouse; Department of Neurology (B.S.), Saint-Antoine Hospital, APHP, Paris; Department of Neurology (A.F., T.M.), University Hospital of Dijon; Department of Neurology (J.d.S.), University Hospital of Strasbourg; Department of Neurology (F.T., P.C.), University Hospital of Clermont-Ferrand; Department of Neurology (B.B.), University Hospital of Rouen, France; Department of Neurology (V.D.), University Hospital of Liège, Belgium; APHM (A.R., J.P.), Hôpital de la Timone, Pôle de Neurosciences Cliniques, Service de Neurologie, Marseille; Department of Neurology (P.L.), University Hospital of Montpellier; Department of Neurology (A.T.), University Hospital of Reims, URCA Reims, and LPN EA 2027 University Paris 8, Saint-Denis; and Department of Neurology (C. Lebrun), University Hospital of Nice, France.
Objective:
To describe the clinico-radiologic outcome of MS patients with natalizumab-related progressive multifocal leukoencephalopathy (Nz-PML) surviving and receiving disease-modifying therapy (DMT).
Methods:
We describe clinical and radiologic evolution of Nz-PML survivors in an observational retrospective multicenter cohort to clarify the effect of different subsequent MS DMT strategies. Twenty-three patients from 11 centers were analyzed. Outcomes were (1) clinical efficacy of post-PML MS DMT, (2) radiologic efficacy of post-PML MS DMT, (3) radiologic evolution of PML lesion, and (4) disability progression.
Results:
There was no clinical worsening of PML symptoms with a stability of Expanded Disability Status Scale at the last follow-up. No relapse was reported with fingolimod and dimethyl fumarate. No radiologic worsening of Nz-PML lesion was observed at the end of the follow-up.
Conclusion:
In this large cohort of patients with Nz-PML, MS therapies given after Nz discontinuation were not associated with PML worsening. A larger cohort with longer follow-up will be necessary to confirm this therapeutic strategy.
Insights
Multiple sclerosis (MS) patients surviving natalizumab-related progressive multifocal leukoencephalopathy (Nz-PML) showed no worsening of PML or disability after subsequent disease-modifying therapies (DMTs). This suggests DMTs may be safe for Nz-PML survivors.
Area of Science:
- Neurology
- Immunology
- Infectious Diseases
Background:
- Natalizumab is associated with progressive multifocal leukoencephalopathy (PML) in multiple sclerosis (MS) patients.
- Survivors of natalizumab-related PML (Nz-PML) require careful management regarding subsequent disease-modifying therapies (DMTs).
- Understanding the safety and efficacy of post-PML DMTs is crucial for patient outcomes.
Purpose of the Study:
- To evaluate the clinical and radiologic outcomes of MS patients who survived Nz-PML and received subsequent DMT.
- To clarify the effect of different MS DMT strategies after Nz-PML.
- To assess disability progression in Nz-PML survivors on DMT.
Main Methods:
- Observational, retrospective, multicenter cohort study.
- Analysis of 23 Nz-PML survivors from 11 centers.
- Assessment of clinical efficacy, radiologic efficacy, PML lesion evolution, and disability progression.
Main Results:
- No clinical worsening of PML symptoms or disability progression (Expanded Disability Status Scale) was observed.
- No MS relapses occurred in patients treated with fingolimod or dimethyl fumarate.
- No radiologic worsening of Nz-PML lesions was noted at the final follow-up.
Conclusions:
- MS therapies initiated after natalizumab discontinuation in Nz-PML survivors were not associated with PML worsening.
- Subsequent DMTs appear safe in Nz-PML survivors, showing stable clinical and radiologic outcomes.
- Further research with larger cohorts and longer follow-up is needed to confirm these findings.
