NCT04372615 · University of Utah
The ExTINGUISH Trial of Inebilizumab in NMDAR Encephalitis
(ExTINGUISH)
What this study is about
Determine the difference in the modified Rankin score at 16 weeks in participants with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis treated with "first-line" immunomodulatory therapies provided as standard-of-care, and either inebilizumab (experimental agent) or placebo.
View original scientific description
Determine the difference in the modified Rankin score at 16 weeks in participants with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis treated with "first-line" immunomodulatory therapies provided as standard-of-care, and either inebilizumab (investigational agent) or placebo.
Interventions
DRUG
Inebilizumab
RCP: Blinded treatment on Day 1, Day 15, * Inebilizumab group: Inebilizumab 300 mg intravenous (IV) * Placebo group: IV matching placebo Prior to enrollment, all participants will receive standard of care, including high-dose corticosteroids (minimum of 3 days of treatment, 1 g methylprednisolone daily or equivalent) AND either IVIg (total dose range between 1.2 and 2 g/kg) OR plasmapheresis (defined as 5 or 6 exchanges). Rescue therapy will be given to participants in either treatment group based on the results of the Week 6 assessments. Rescue therapy is cyclophosphamide 750 mg/m2 IV followed by additional doses every 28-30 days until the mRS score is ≤ 3 (at site Principal Investigator's discretion under standard of care).
DRUG
Placebo
The placebo group will receive IV matching placebo on Day 1 and Day 15,
Primary outcome measures
Change of modified Rankin score at 16 weeks
Time frame: 16 weeks
Change in modified Rankin score (mRS) (0 to 6; 0=normal and 6=death) at 16 weeks determined by rank analyses, integrating need for rescue therapy and time to achievement of the mRS.
Inebilizumab safety measures by the number of treatment-emergent adverse events and serious adverse events
Time frame: 96 weeks
Inebilizumab safety, as measured by the number of treatment-emergent adverse events (TEAEs) and treatment-emergent serious adverse events (TESAEs)
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Diagnosis of NMDAR encephalitis, defined by both a and b: 1. A subacute onset of change in mental status consistent with autoimmune encephalitis, 2. A positive cell-based assay for anti-NMDA receptor IgG antibody in the CSF confirmed in study-specified laboratories. 2. Participants, ≥ 12 years of age at the time of informed consent. Participants under 18 years of age must weigh ≥40 kilograms. 3. Written informed consent and any locally required authorization (e.g., Health Insurance Portability and Accountability Act \[HIPAA\] in the United States of America \[USA\], European Union \[EU\] Data Privacy Directive in the EU) obtained from the participant/legal representative prior to performing any protocol-related procedures, including screening evaluations. 4. Non-sterilized participants who are sexually active with a partner capable of becoming pregnant must use a condom with spermicide from Day 1 through to the end of the study and must agree to continue u
Where
- Birmingham, Alabama
- Phoenix, Arizona
- Scottsdale, Arizona
- Orange, California
- Sacramento, California
- Aurora, Colorado
- New Haven, Connecticut
- Jacksonville, Florida
- Miami, Florida
- Atlanta, Georgia
- Chicago, Illinois
- Iowa City, Iowa
And 19 more locations — see the full list below.
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jul 1, 2025 · Source of record for eligibility and locations