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Immunoadsorption Therapy in Managing NMDAR Antibodies Encephalitis

Phase 2
Recruiting
Conditions
Anti-NMDAR Encephalitis
Interventions
Drug: IA session
Drug: Rituximab
Registration Number
NCT03274375
Lead Sponsor
Assistance Publique - H么pitaux de Paris
Brief Summary

The purpose of the study is to assess the efficacy of immunoadsorption therapy (IA) on improving the neurological status of severe pediatric anti-NMDAR encephalitis patients.

Detailed Description

Anti-NMDA-Receptor (NMDAR) encephalitis, the most frequent autoimmune encephalitis after Acute Demyelinating encephalomyelitis (ADEM), affects children with predominant movement disorders, decline of consciousness, psychiatric symptoms, language dysfunction, seizures, dysautonomic symptoms. The cerebrospinal fluid (CSF) is most often abnormal with lymphocytic pleocytosis, CSF-specific oligoclonal bands with intrathecal synthesis of anti-NMDAR antibodies. Antibody titres in CSF and serum seem correlated with clinical outcome. Early start of immunotherapy has been reported to improve clinical outcome and associated with less relapses. In a recent large series (211 children/577), 77% of the patients were admitted to Intensive Care Unit (ICU) at the beginning. Within the group of children, first-line immunotherapy (95%) consisted of corticosteroids (89%), and/or intravenous immunoglobulins (IgIV) (83%), and/or plasma exchange (28%) with failure in 46%. The second-line immunotherapy consisting in rituximab (24%) and/or cyclophosphamide (16%) was proposed in 32%, and tended to be associated with good outcome (OR=3.35, CI: 0.86-12.98, p=0.081 for 53 children; statistical significance was achieved for the entire population including adults (OR: 2.69, CI: 1.24-5.80, p = 0.012) and less relapses.

In investigators' experience, the clinical benefit of rituximab is delayed over one month, while children go on worsening (50% admitted in ICU) thus claiming for faster removal of the antibodies. Plasma exchange is proposed in most of the series as alternative or combined treatment in the acute stage (first-line immunotherapy); recently, another plasmatherapy, immunoadsorption therapy (IA), has been reported as an efficient therapeutic approach in 11/13 patients. In this retrospective study, patients received a median of 6 IA sessions within a median period of 8 days with relevant clinical improvement. However these encouraging results and investigators' experience in few children need further prospective and standardized evaluation.

In IANMDAR study, each patient will receive 10 IA sessions during 28 days maximum. Rituximab will be given each week for 4 weeks (one injection by week +/- 3 days):

* at least 1 day before each IA session

* the 4 injections should be done before V2 (Day 28 after the inclusion)

To assess the efficacy of IA-therapy at short term, the neurological status of patients will be evaluated before and after the 10 IA sessions using the Pediatric Cerebral Performance Category Scale (PCPCS) and the modified Rankin Scale (mRS).

To assess the efficacy of IA-therapy at long term, patients will have a standardized follow-up during two years including neuropsychological evaluation at 1 year and at 2 years (see below for further details).

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
20
Inclusion Criteria
  • Age: 0-18 years inclusive
  • Autoimmune encephalitis with positive anti-NMDAR antibodies in CSF (definite anti-NMDAR encephalitis according to Graus's criteria (Graus et al., 2016).
  • PCPCS and mRS at 4 or over at the inclusion after first line therapy (steroids and/or IgIV) when Rituximab therapy is warranted
  • Parents or legal guardians signed the Informed consent form
  • Social insurance affiliation
Read More
Exclusion Criteria
  • Autoimmune encephalitis without NMDAR antibodies

  • PCPCS and mRS scores under 4 after first-line therapy

  • Contraindication to perform central vascular access

  • Pregnancy, breastfeeding or absence of effective contraception (including abstinence) in a pubertal patient.

  • Contraindication to perform IA therapy :

    • Clinical conditions that prohibit transitory volume changes
    • Indications that prohibit anticoagulation using Heparin and/or ACD-A solutions
    • History of hypercoagulability
    • Generalized viral, bacterial and/or mycotic infections
    • Severe immune deficiencies (e.g. AIDS)
    • Suspected allergies against sheep antibodies or agarose
Read More

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
IA sessionIA session* 4 Rituximab injections * 10 IA sessions
IA sessionRituximab* 4 Rituximab injections * 10 IA sessions
Primary Outcome Measures
NameTimeMethod
Change in Neurological status evaluated with the modified Rankin Scale (mRS)before and after the 10 IA sessions, 28 days maximum

at least reduction of 1 point in mRS between the two evaluations is expected

Change in Neurological status evaluated with the Pediatric Cerebral Performance Category Scale (PCPCS)before and after the 10 IA sessions, 28 days maximum

at least reduction of 1 point in PCPCS between the two evaluations is expected

Secondary Outcome Measures
NameTimeMethod
CMS to assess memory2 years
Number of adsorbers used for each patient28 days

To assess tolerance of IA therapy

Biological evolution of NMDAR antibodies tested in CSF28 days

at diagnosis and after IA sessions

Duration of hospitalization in ICU and pediatric neurology unit28 days

To assess immunoadsorption therapy at short term in pediatric severe anti-NMDAR encephalitis patients

Movement disorders assessment with video taping6 months

To assess Immunoadsorption therapy at long term

Proteinorachia1 year

titration at 1 year

Need for mechanical ventilation28 days

To assess immunoadsorption therapy at short term in pediatric severe anti-NMDAR encephalitis patients

Need of hospitalization in ICU and pediatric neurology unit28 days

To assess immunoadsorption therapy at short term in pediatric severe anti-NMDAR encephalitis patients

Movement disorders assessment with the Movement Disorder Childhood Scale2 years

To assess Immunoadsorption therapy at long term

Occurrence of hypotension with need for vasopressive treatment28 days

To assess tolerance of IA therapy

Total number of sessions28 days

To assess tolerance of IA therapy

Duration of hospitalization in functional rehabilitation unit2 years

To assess Immunoadsorption therapy at long term

Neuropsychological assessment for cognitive and behavioral status with Brief Inventory of Executive Functions (BRIEF)at 2 years
Rey's figure test to evaluate visuospatial abilities and memory2 years
Digit span to assess memory2 years
Need for vasopressive treatment28 days

To assess immunoadsorption therapy at short term in pediatric severe anti-NMDAR encephalitis patients

Time of recovery of independent daily-life activities28 days

independent ambulation, enteral feeding, responsiveness to simple instructions and verbal communication (first word)

Evolution of movement disorders assessed by the Movement Disorder Childhood Scale with video-taping, performed before and after IA therapy28 days

To assess immunoadsorption therapy at short term in pediatric severe anti-NMDAR encephalitis patients

Titration of NMDAR antibodies in serum before and after the first and the last (tenth) IA session28 days

To assess immunoadsorption therapy at short term in pediatric severe anti-NMDAR encephalitis patients

Duration of each immunoadsorption treatment28 days

To assess tolerance of IA therapy

Occurrence of vascular access complications : Infections (number, duration of antibiotics used), inadvertent removal, inefficiency (duration of retention of each vascular access)28 days

To assess tolerance of IA therapy

Adverse events of associated treatments28 days

To assess tolerance of IA therapy

PCPCS scoreat 2 years

To assess Immunoadsorption therapy at long term

Neuropsychological assessment for cognitive and behavioral status with Wechsler scalesat 2 years
Neuropsychological assessment for cognitive and behavioral status with Child Behavior Checklist (CBCL)at 2 years
Visual attention evaluated with NEPSY scaleat 2 years
Name and duration of medication for behavioral disorders and sleep disorders28 days

To assess immunoadsorption therapy at short term in pediatric severe anti-NMDAR encephalitis patients

Biological evolution of NMDAR antibodies tested in serum28 days

before and after IA sessions

Duration of use of medication for sedation by pharmaceutical class28 days

to assess need of sedation

Total duration of the immunoadsorption therapy28 days

To assess tolerance of IA therapy

School attendance (special school or not) and rehabilitation attendance2 years

To assess Immunoadsorption therapy at long term

Neuropsychological assessment for cognitive and behavioral status with Pediatric Quality of Life questionnaire (PedsQL)at 2 years
Movement disorders assessment with video-tapingat 2 years

To assess Immunoadsorption therapy at long term

Presence of NMDAR antibodies in CSF1 year

titration at 1 year

Presence of oligoclonal bands in serum6 months

checked at 6 months

Presence of oligoclonal bands in CSF1 year

checked at 1 year

Occurrence of dysautonomic events (linked to the pathology): cardiac arrhythmia and heart rate events, flush, apnea28 days

To assess tolerance of IA therapy

mRS scoreat 2 years

To assess Immunoadsorption therapy at long term

Presence of NMDAR antibodies in serum1 year

titration at 1 year

Need of hospitalization in functional rehabilitation unit2 years

To assess Immunoadsorption therapy at long term

Occurrence and date of relapses2 years
Number of lymphocytes in serum1 year

checked at 1 year

Number of lymphocytes in CSF1 year

checked at 1 year

Trial Locations

Locations (1)

H么pital Necker Enfants-Malades

馃嚝馃嚪

Paris, France

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