Back To Results

The ExTINGUISH Trial of Inebilizumab in NMDAR Encephalitis

UCI Specialty Area: Neurology
Principal Investigator: Xiao-Tang Kong
Official Title: A Phase-2b, Double-Blind, Randomized Controlled Trial to Evaluate the Activity and Safety of Inebilizumab in Anti-Nmda Receptor Encephalitis and Assess Markers of Disease
A Study On:
Brain - Neurologic/ Psychologic
Encephalitis

Study Description

N-methyl-D-aspartate receptor (NMDAR) encephalitis is one of the most common causes of autoimmune encephalitis, with prevalence exceeding herpes encephalitis in industrialized nations. Typically, the disease affects patients age 10-50 causing prominent psychiatric symptoms, altered consciousness, seizures, movement disorders and life-threatening dysautonomia. Intensive care, including cardiorespiratory support is required in 75% of cases. The diagnosis is confirmed by detection of IgG autoantibodies against central nervous system NMDAR in the cerebrospinal fluid. Despite the severity of the illness, NMDAR encephalitis is a treatable neurological disease, with retrospective case series establishing the benefit of off-label intravenous steroids and immunoglobulins. These treatments are presumed to work through effects on IgG NMDAR autoantibody levels in the CSF, although prospective data informing predictors of treatment responses are limited. Even with prompt treatment, ~50% of patients remain disabled, requiring prolonged hospital admissions. Various off-label therapies have been proposed as "second-line" treatments in NMDAR encephalitis. The majority of second-line treatments target circulating B-cells with various degrees of blood brain penetrance and efficacy, and poor consensus on the timing, dose and route of delivery of candidate agents. High-quality evidence is needed to inform the treatment of NMDAR encephalitis. Inebilizumab is a promising therapeutic monoclonal antibody for the treatment of NMDAR encephalitis. This humanized monoclonal antibody against the B-cell surface antigen CD19 was recently shown to be safe and efficacious in the treatment of neuromyelitis optica spectrum disorder-another antibody-mediated disorder of the central nervous system. Compared to other off label B-cell depleting therapies, such as rituximab, inebilizumab not only depletes CD20+ B-cells, but also CD20- plasmablasts and plasma cells, resulting in robust and sustained suppression of B-cell expression. The ExTINGUISH Trial will randomize 116 participants with moderate-to-severe NMDAR encephalitis to receive either inebilizumab or placebo in addition to first-line therapies. Patient outcomes will be ascertained at standard intervals using the modified Rankin scale and accepted safety measures (primary outcomes at 16 weeks), together with comprehensive validated neuropsychological tests, bedside cognitive screening tools, quality of life/ functional indices, and outcome prediction measures. Clinical data will be combined with quantitative measures of NMDAR autoantibody titers and cytokines implicated in B-cell activation and antibody production within the intrathecal compartment to identify treatment responders, inform the biologic contributors to outcomes, and evaluate for biomarkers that may serve as early predictors of favorable outcomes in future clinical trials in NMDAR encephalitis. The ExTINGUISH Trial will prospectively study an optimized B-cell depletion therapy to promote better long-term outcomes in NMDAR encephalitis, to determine more meaningful cognitive endpoints, and to identify better biologic biomarkers to predict outcome.

Eligibility

Inclusion Criteria:

  • Inclusion Criteria 1. 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.
  1. Age ≥ 18 years 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.
  1. Females of childbearing potential who are sexually active with a nonsterilized male partner must agree to use a highly effective method of contraception beginning at screening or upon discharge from hospitalization/inpatient rehabilitation (for participants who were incapacitated at the time of screening), and to continue precautions for 6 months after the final dose of investigational product.
  1. Nonsterilized males who are sexually active with a female partner of childbearing potential must agree to use a highly effective method of contraception at screening or upon discharge from hospitalization/inpatient rehabilitation (for participants who were incapacitated at the time of screening), and to continue precautions for 3 months after the final dose of investigational product. Male patients with female partners of childbearing potential must have that female partner use at least one form of highly effective contraception, starting at least one menstrual cycle before (the male patient's) first study drug administration and continuing until at least 3 months after their male partner's last dose of the study drug.
  1. Willing to forego other immunomodulatory therapies (investigational or otherwise) for NMDAR encephalitis during the study.
  1. Patient must have received at least 3 days of methylprednisolone 1000 mg IV or equivalent corticosteroid within 30 days prior to randomization (Day 1). In addition, patients must have received EITHER of the following treatments within 30 days before randomization.
  1. IVIg, at a minimum dose of 2 g/kg
  2. Plasma exchange or plasmapheresis, with a minimum of 5 treatments. NOTE: These treatments may be provided during the screening period, but must be completed prior to randomization.
  1. mRS of ≥3 at the screening visit, indicating at least moderate disability. 9. Ability and willingness to attend study visits and complete the study
A female nurse attentively holds a tablet, ready to assist with patient care and medical information.

Interested in Participating in this Trial?

Thank you for your interest with our team.

One of our specialists will be in contact with you soon.

Privacy Policy

University of California, Irvine - Study Information Sheet

UCI Center for Clinical Research Potential Participant Database

Lead Researcher
Maheswari Senthil, MD
UCI Center for Clinical Research

In the instance of parental permission, “You” refers to “Your child.”

  • Please read the information below and ask questions about anything that you do not understand. A
    researcher listed above will be available to answer your questions.
  • You are being asked to participate in a clinical research potential participant database to identify
    potential clinical research studies you may be eligible for. Participation in this database is voluntary.
    You may choose to skip any question. You may refuse to participate or discontinue your involvement
    at any time without penalty or loss of benefits. You are free to withdraw from this database at any
    time. If you decide to withdraw from this database you should notify the research team
    immediately    .
  • You are eligible to participate in this study if you may be interested in participating in a research trial at UCI Health
  • We would like to interview you to learn more about your eligibility for current clinical research studies at UCI. The interview will last about 5-30 minutes, depending on the extent of your medical history.
  • Possible risks/discomforts associated with the database are hearing about potential clinical research studies that may not be of interest to you, invasion of your privacy, or a potential breach of confidentiality.
  • There are no direct benefits from participation in the database. However, this database may help inform you on clinical research studies that you may be eligible for. Participation in UCI clinical research studies help us gain important data and knowledge that may lead to improved treatment options for people with similar conditions to you in the future.
  • There are no alternative procedures available. The only alternative is not to participate in this study.
  • There is no compensation for your participation in this database.
  • There is no cost to you for participation in this database.
  • All information collected will be stored confidentially in a world-class securely-hosted application, “RealTime CTMS,” with robust data protections and encryption. This application has HIPAA compliant architecture and application rules to ensure data privacy and regulatory compliance.
  • Researchers will use your information to assess your eligibility for current and future clinical research studies at UCI. You may opt out at any time.
  • The research team, authorized UCI personnel, and regulatory entities, may have access to your study records to protect your safety and welfare.
  • While the research team will make every effort to keep your personal information confidential, it is possible that an unauthorized person might see it. We cannot guarantee total privacy.
  • Future Research Use
    Researchers will use your information to conduct this study. Once the study is done using your information, we may share them with other researchers so they can use them for other studies in the future. We will not share your name or any other private identifiable information that would let the researchers know who you are. We will not ask you for additional permission to share this de-identified information
  • Data Retention - In accordance with UC Office of the President policy, information will be retained for 10 years after the end of the calendar year in which the research is completed.
  • If, during the course of this study, significant new information becomes available that may relate to your willingness to continue to participate, this information will be provided to you by the research team listed at the top of the form.
  • If you have any comments, concerns, or questions regarding the conduct of this research please contact the researchers listed at the top of this form
  • Please contact the UCI Institutional Review Board by phone, (949) 824-8170, by e-mail at IRB@research.uci.edu or at 160 Aldrich Hall, Irvine, CA 92697-7600 if you are unable to reach the researchers listed at the top of the form and have general questions; have concerns or complaints about the research; have questions about your rights as a research subject; or have general comments or suggestions.
What is an IRB? An Institutional Review Board (IRB) is a committee made up of scientists and nonscientists. The IRB’s role is to protect the rights and welfare of human subjects involved in research. The IRB also assures that the research complies with applicable regulations, laws, and institutional policies. UCI