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Not yet recruiting NCT07583641

A Study to Learn About How Well the Medicine Efgartigimod Works to Treat Autoimmune Encephalitis In Children 12 Years or Older and Adults

Phase II Interventional Autoimmune Encephalitis (AE)

For patients and families

In plain language

An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.

What is being studied
The protocol lists: Efgartigimod PH20 (ARGX-113) SC, Placebo PH20 SC.
Who it may be relevant to
Registry conditions: Autoimmune Encephalitis (AE). Basic parameters: from 12 years · All.
What needs checking
Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
Where it takes place
Center list to be confirmed — check the primary protocol.
Next step
Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →

Unsure about the terms? Read our patient guide →

Official title

A Global, Multicenter, Randomized, Double-Blinded, Placebo-Controlled, Phase 2 Study to Evaluate the Efficacy, Safety, and Tolerability of Efgartigimod PH20 SC in Adult and Adolescent Participants With Autoimmune Encephalitis

Overview

The POLARIS study is designed to evaluate how well efgartigimod PH20 SC may work (called "efficacy") and how safe it is for people diagnosed with Autoimmune Encephalitis (AIE). The study consists of 4 parts: in part A participants will receive efgartigimod SC; in part B, participants will be randomized to receive either efgartigimod SC or placebo; in part C, participants who completed part B will receive efgartigimod SC; in part D, participants who completed part C will be observed after their last dose of efgartigimod SC. If AIE symptoms return, efgartigimod SC treatment may be restarted during this time. The maximum overall study duration for participants is up to 3 years. More information can be found in clinicaltrials.argenx.com/polaris

Detailed description

The study is designed to address the unmet need for effective immunomodulatory therapy in AIE, enrolling patients across multiple antibody-defined subgroups, with the anti-NMDAR encephalitis group serving as the primary cohort for statistical analysis.

Interventions

  • Biological Efgartigimod PH20 (ARGX-113) SC
    subcutaneous administrations of efgartigimod PH20 SC given by prefilled syringe (PFS). For participants aged 12 to \<18 years with body weight ≤50 kg, the study drug will be administered by vial and syringe.
  • Other Placebo PH20 SC
    subcutaneous administrations of placebo PH20 SC given by prefilled syringe (PFS). For participants aged 12 to \<18 years with body weight ≤50 kg, the study drug will be administered by vial and syringe

Primary outcome measures

  • Change in CASE score in the NMDAR population [Time frame: up to week 24]
Secondary outcome measures (12)
  • Change in mRS [Time frame: up to week 8]
  • Change in CASE score [Time frame: up to week 8]
  • Change in MoCA total score [Time frame: up to week 8]
  • Change in NPI-C total score [Time frame: up to week 8]
  • Change from baseline in CGI-S [Time frame: up to week 8]
  • Change from baseline in PGI-S [Time frame: up to week 8]
  • Change from baseline in CGI-C [Time frame: up to week 8]
  • Change from baseline in PGI-C [Time frame: up to week 8]
  • Incidence and severity of AEs [Time frame: up to week 8]
  • Incidence and severity of SAEs [Time frame: up to week 8]
  • Trough efgartigimod serum concentrations over time [Time frame: up to week 8]
  • Percent change from baseline in total IgG levels in serum over time [Time frame: up to week 8]

Eligibility criteria

Inclusion criteria

  • Is at least 12 years of age.
  • Meeting at least the criteria for possible AIE according to the Graus criteria.
  • Part A:

Must not have received prior treatment for AIE with PLEX or Ig (participants may have received glucocorticoids); and must not have received PLEX or Ig for any other medical condition in the last 3 months

\- Part B: Either completing Part A, or If directly entering Part B, must have received first-line treatment for AIE (i.e. corticosteroids, PLEX, and/or Ig) and have a CASE score of 3 or higher, or a score of 2 or higher in a single sub-item

Exclusion criteria

  • Known anti-myelin oligodendrocyte glycoprotein (anti-MOG) antibody positivity.
  • Any medical condition that would interfere with an accurate assessment of clinical symptoms of AIE.
  • Recent major surgery (within 3 months of screening) or intention to have major surgery during the study, except for surgeries for AIE-related teratomas and thymomas.
  • History (within 12 months before screening) of current alcohol, drug (including recreational or prescribed cannabinoids), or medication abuse.
  • Psychiatric or cognitive impairment unrelated to AIE.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation
Randomized
Model
Parallel assignment
Masking
Triple blind
Primary purpose
Treatment

Study locations

Center list to be confirmed — check the primary protocol.

Identifiers

NCT: NCT07583641 · ARGX-113-22-AIE-2001

Primary sources (government registries)

View this study on ClinicalTrials.gov ↗