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.
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
Study summary
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
Eligibility
Sex
ALL
Min age
12 Years
Max age
—
Healthy volunteers
No
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.
Primary outcome measure(s)
Change in CASE score in the NMDAR population — up to week 24 CASE= Clinical Assessment Scale in Autoimmune Encephalitis; NMDAR=N-methyl-D-aspartate receptor; Neuropsychological Status. The CASE (Clinical Assessment Scale in AIE) includes an assessment of 9 items: seizure, memory dysfunction, psychiatric symptoms, consciousness, language problems, dyskinesia/dystonia, gait instability and ataxia, brainstem dysfunction, weakness. This overall CASE total score ranges from 0 to 27, with a higher score indicating a greater degree of disability.
This page summarises publicly available registry data for informational purposes — not medical advice. Eligibility is determined by each study team; patients should discuss participation with their clinician.
We use cookies to analyse site traffic and improve your experience. With your consent, we may also use cookies for advertising. You can change your choice at any time on our Cookie Policy page. See also our Privacy Policy.