Study of Inebilizumab in Pediatric Subjects With Neuromyelitis Optica Spectrum Disorder

An Open-Label Multicenter Study to Evaluate the Pharmacokinetics, Pharmacodynamics, and Safety of Inebilizumab in Pediatric Subjects With Neuromyelitis Optica Spectrum Disorder

A Phase 2, open-label, multicenter study to evaluate the pharmacokinetics (PK), pharmacodynamics (PD), and safety of inebilizumab in eligible pediatric participants 2 to < 18 years of age with recently active neuromyelitis optica spectrum disorder (NMOSD) who are seropositive for autoantibodies against aquaporin-4 (AQP4-immunoglobulin [Ig]G).

Study Overview

• Status: Recruiting
• Conditions: Neuromyelitis Optica Spectrum Disorder
• Intervention / Treatment: Drug: Inebilizumab

Detailed Description

Approximately 15 participants to be enrolled and receive Inebilizumab administered intravenously over 28 weeks. The maximum trial duration per participant is approximately 80 weeks, including up to 4 week screening period, 9 visits during a 28 week open-label treatment period, and approximately 4 visits during a 52 week follow-up period. Safety evaluations will be performed regularly throughout the course of the study.

Acquired from Horizon in 2023.

• Study Type: Interventional
• Enrollment (Estimated): 15
• Phase: Phase 2

Expanded Access

Available outside the clinical trial. See expanded access record.

Contacts and Locations

• Study Contact: Name: Amgen Call Center; Phone Number: 866-572-6436; Email: medinfo@amgen.com

Study Locations

• Argentina
  • Ciudad Autónoma de BuenosAires
    • Parque Patricios, Ciudad Autónoma de BuenosAires, Argentina, C1245AAM
      • Recruiting
      • Hospital de Pediatría S.A.M.I.C.- Prof. Dr. Juan P. Garrahan
• Brazil
  • Porto Alegre/RS, Brazil, 90610-000
    • Recruiting
    • Hospital Sao Lucas Da Pontificia Universidade Catolica Do Rio Grande Do Sul (PUCRS)
  • São Paulo, Brazil, 05403-000
    • Recruiting
    • Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo
    • Contact: Neusa Sakita; Phone Number: +551126618676; Email: Neusa.sakita@hc.fm.usp.br
    • Principal Investigator: Barbosa Paolilo, MD
  • São Paulo, Brazil, 01228-000
    • Recruiting
    • CPQuali Pesquisa Clínica Sao Paulo
  • Estado de Bahia
    • Salvador, Estado de Bahia, Brazil, 40050-410
      • Recruiting
      • Hospital Santa Izabel-Rua Floriano Peixoto 300
• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5G 1X8
      • Recruiting
      • Hospital for Sick Children
• France
  • Val-de-Marne
    • Le Kremlin-Bicêtre, Val-de-Marne, France, 94275
      • Recruiting
      • Centre Hospitalier Universitaire de Bicêtre
      • Contact: Milanthika Nanediri; Phone Number: +33145213014; Email: milanthika.nanediri@aphp.fr
      • Principal Investigator: Deiva Kumaran, MD, PhD
• Netherlands
  • South Holland
    • Rotterdam, South Holland, Netherlands, 3015 GD
      • Recruiting
      • Erasmus MC Sophia Children's Hospital-Wytemaweg 80
• Poland
  • Gdansk, Poland, 80-952
    • Recruiting
    • Uniwersyteckie Centrum Kliniczne w Gdansku - Smoluchowskiego 17
• Serbia
  • Belgrade
    • Belgrade, Belgrade, Serbia, 11000
      • Recruiting
      • Clinic for Neurology and Psychiatry for Children and Youth
• Spain
  • Barcelona
    • Espluges de Llobregat, Barcelona, Spain, 08950
      • Recruiting
      • Hospital Sant Joan de Deu - PIN
• Sweden
  • Stockholm County
    • Stockholm, Stockholm County, Sweden, 17176
      • Recruiting
      • Karolinska Universitetssjukhuset Solna
• United Kingdom
  • London, City of
    • London, London, City of, United Kingdom, SE1 7EH
      • Recruiting
      • Evelina London Children's Hospital
    • London, London, City of, United Kingdom, WC1N 3JH
      • Recruiting
      • Great Ormond Street Hospital - PPDS
  • West Midlands
    • Birmingham, West Midlands, United Kingdom, B4 6NH
      • Recruiting
      • Birmingham Women's and Children's NHS Foundation Trust
• United States
  • California
    • La Jolla, California, United States, 92037-1337
      • Recruiting
      • UCSD Altman Clinical and Translational Research Institute Building
    • Loma Linda, California, United States, 92354
      • Recruiting
      • Loma Linda University Children's Hospital - PIN
  • Massachusetts
    • Boston, Massachusetts, United States, 02115
      • Recruiting
      • Massachusetts General Hospital
  • Texas
    • Dallas, Texas, United States, 78701
      • Recruiting
      • University of Texas Southwestern Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 2 years to 17 years (Child)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Male or female participants, minimum body weight of 15 kg, age 2 to < 18 years at the time of screening.
• Positive serum anti-AQP4-IgG result at screening and diagnosed with NMOSD according to the criteria of Wingerchuk et al, 2015.
• Documented history of one or more NMOSD acute relapses within the last year, or 2 or more NMOSD acute relapses within 2 years prior to screening.

Exclusion Criteria:

• Any condition that, in the opinion of the Investigator, would interfere with the evaluation or administration of the Investigational Product or interpretation of participant safety or study results.
• Concurrent/previous enrollment in another clinical study involving an investigational treatment within 4 weeks or 5 published half-lives of the investigational treatment, whichever is the longer, prior to Day 1.
• Evidence of significant hepatic, renal, or metabolic dysfunction or significant hematological abnormality (one repeat test may be conducted to confirm results within the same screening period).
• B-cell counts < one-half of the lower limit of normal (LLN) for age according to the central laboratory.

• Receipt of the following at any time prior to Day 1:

  1. Alemtuzumab
  2. Total lymphoid irradiation
  3. Bone marrow transplant
  4. T-cell vaccination therapy
• Receipt of rituximab or any experimental B-cell depleting agent within 6 months prior to screening unless B-cell counts have returned to ≥ one-half the LLN.
• Receipt of intravenous immunoglobulin (IVIG) within one month prior to Day 1.

• Receipt of any of the following within 2 months prior to Day 1:

  1. Cyclosporine
  2. Methotrexate
  3. Mitoxantrone
  4. Cyclophosphamide
  5. Tocilizumab
  6. Satralizumab
  7. Eculizumab
• Receipt of natalizumab (Tysabri®) within 6 months prior to Day 1.
• Severe drug allergic history or anaphylaxis to 2 or more food products or medicine (including known sensitivity to acetaminophen/paracetamol, diphenhydramine or equivalent antihistamine, and methylprednisolone or equivalent glucocorticoid).
• Diagnosed with a concurrent autoimmune disease that is uncontrolled (unless approved by the medical monitor).
• Recent receipt of live/attenuated vaccine or blood transfusion.

Receipt of any of the following:

1. Any live or attenuated vaccine within 4 weeks prior to Day 1 (administration of killed vaccines and nucleoside-modified mRNA-based vaccines is acceptable; the Sponsor recommends that Investigators ensure all participants are up to date on required vaccinations prior to study entry).
2. Bacillus Calmette Guérin vaccine within one year of screening.

3. Blood transfusion within 4 weeks prior to screening or during screening.

   • Clinically significant serious active or chronic viral, bacterial, or fungal infection that requires treatment with anti-infectives, hospitalization, or, in the Investigator's opinion, represents an additional risk to the participant, within 2 months prior to Day 1.
   • Known history of congenital or acquired immunodeficiency (e.g., due to human immunodeficiency virus [HIV] infection, splenectomy, immunosuppression-related or idiopathic T-cell deficiencies) that predisposes the participant to infection.
   • Positive test for chronic hepatitis B infection at screening, defined as either:

a. Positive hepatitis B surface antigen (HBsAg), or b. Positive hepatitis B core (HBc) antibody (anti-HBc) plus negative hepatitis B surface (HBs) antibody (anti-HBs).

• Positive test for hepatitis C virus antibody.
• Negative test for varicella zoster virus (VZV)-IgG.
• History of cancer, apart from squamous cell or basal cell carcinoma of the skin treated with documented success of curative therapy > 3 months prior to Day 1.
• History of active or latent tuberculosis (TB), or a positive QuantiFERON®-TB Gold test at screening, unless treatment for TB was completed per local guidelines. Participants with latent TB or a positive QuantiFERON®-TB Gold test who are actively on anti-TB treatment can enroll if they have completed at least one month of anti-TB treatment and intend to complete the full course of anti-TB treatment. Participants with an indeterminate QuantiFERON®-TB Gold test result can enroll if a repeat QuantiFERON®-TB Gold test is negative or a tuberculin skin test is negative.

• For participants who may undergo MRI scans:

  1. Unable to undergo an MRI scan (e.g., hypersensitivity to Gd-containing MRI contrast agents, implanted pacemakers, defibrillators, or other metallic objects on or inside the body that limit performing MRI scans), or
  2. Unable to tolerate or comply with the MRI procedure.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Inebilizumab; Infusion of Inebilizumab	Drug: Inebilizumab; Inebilizumab administered intravenously (IV) over a total of 28 weeks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Maximum Observed Concentration (Cmax) of Inebilizumab	Day 1 to Week 28
Area Under the Concentration Versus Time Curve of Inebilizumab from Time 0 to 14 Days Post-dose (AUC0-14d)	Day 1 to pre-dose on Day 15
Area Under the Concentration Versus Time Curve of Inebilizumab from Time 0 Extrapolated to Infinity (AUC0-Inf)	Day 1 to Week 80
Systemic Clearance (CL) of Inebilizumab	Day 1 to Week 80
Terminal Elimination Half-life (t½) of Inebilizumab	Day 1 to Week 80
Volume of Distribution at Steady State (VSS) of Inebilizumab	Day 1 to Week 80
Change from Baseline in Peripheral Cluster of Differentiation (CD)20-positive B-cell Counts	Week 1, Week 2, Week 28, Week 80
Number of Participants Experiencing Treatment-emergent Adverse Events (TEAEs), Serious Adverse Events (SAEs), and Adverse Events of Special Interest (AESIs)	Day 1 to Week 80
Change from Baseline in Serum Chemistry	Week 1, Week 2, Week 28, Week 80
Change from Baseline in Hematology	Week 1, Week 2, Week 28, Week 80
Change from Baseline in Serum Immunoglobulins	Week 1, Week 2, Week 28, Week 80
Change from Baseline in Systolic Blood Pressure	Week 1, Week 2, Week 28, Week 80
Change from Baseline in Diastolic Blood Pressure	Week 1, Week 2, Week 28, Week 80
Change from Baseline in Pulse Rate	Week 1, Week 2, Week 28, Week 80
Change from Baseline in Respiratory Rate	Week 1, Week 2, Week 28, Week 80
Change from Baseline in Body Temperature	Week 1, Week 2, Week 28, Week 80

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Disease Activity: Time to First Relapse		Day 1 to Week 80
Disease Activity: Proportion of Relapse-free Participants		Day 1 to Week 80
Disease Activity: Annualized Relapse Rate		Day 1 to Week 80
Health-Related Quality of Life (HRQoL) change from baseline in Euro Quality of Life-5 Dimension Youth score	Change in baseline for the 5 dimensions: mobility, looking after myself, doing usual activities, having pain or discomfort, and feeling worried, sad, or unhappy. A higher score indicates onset or worsening of an affective disorder.	Day 1 to Week 80
HRQoL change from baseline in Pediatric Quality of Life Inventory	Change in baseline comprised from 4 generic core scales: Physical Functioning, Emotional Functioning, Social Functioning, and School Functioning. A higher score indicates a better quality of life.	Day 1 to Week 80
Visual Acuity change from baseline		Day 1 to Week 80
Change From Baseline in Expanded Disability Status Scale	Change in baseline comprised from results of 8 Functional Systems: Visual, Brainstem, Pryamidal, Cerebellar, Sensory, Bowel, Bladder, and Cerebral. A higher score indicates a higher grade of impairment and disability.	Day 1 to Week 80
Anti-drug antibody (ADA) rate		Day 1 to Week 80

Collaborators and Investigators

• Sponsor: Amgen
• Investigators: Study Director: MD, Amgen

Publications and helpful links

Helpful Links

• AmgenTrials clinical trials website

Study record dates

Study Major Dates

• Study Start (Actual): July 3, 2023
• Primary Completion (Estimated): April 13, 2027
• Study Completion (Estimated): April 13, 2027

Study Registration Dates

• First Submitted: July 22, 2022
• First Submitted That Met QC Criteria: September 19, 2022
• First Posted (Actual): September 22, 2022

Study Record Updates

• Last Update Posted (Actual): December 5, 2025
• Last Update Submitted That Met QC Criteria: December 3, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: NMOSD
• Additional Relevant MeSH Terms: Nervous System Diseases; Autoimmune Diseases; Immune System Diseases; Eye Diseases; Demyelinating Autoimmune Diseases, CNS; Autoimmune Diseases of the Nervous System; Demyelinating Diseases; Myelitis, Transverse; Optic Neuritis; Optic Nerve Diseases; Cranial Nerve Diseases; Neuromyelitis Optica; inebilizumab
• Other Study ID Numbers: VIB0551.P2.S2.NMO; 2023-510007-22 (EudraCT Number)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified individual patient data for variables necessary to address the specific research question in an approved data sharing request.
• IPD Sharing Time Frame: Data sharing requests relating to this study will be considered beginning 18 months after the study has ended and either 1) the product and indication have been granted marketing authorization in both the US and Europe or 2) clinical development for the product and/or indication discontinues and the data will not be submitted to regulatory authorities. There is no end date for eligibility to submit a data sharing request for this study.
• IPD Sharing Access Criteria: Qualified researchers may submit a request containing the research objectives, the Amgen product(s) and Amgen study/studies in scope, endpoints/outcomes of interest, statistical analysis plan, data requirements, publication plan, and qualifications of the researcher(s). In general, Amgen does not grant external requests for individual patient data for the purpose of re-evaluating safety and efficacy issues already addressed in the product labelling. Requests are reviewed by a committee of internal advisors. If not approved, a Data Sharing Independent Review Panel will arbitrate and make the final decision. Upon approval, information necessary to address the research question will be provided under the terms of a data sharing agreement. This may include anonymized individual patient data and/or available supporting documents, containing fragments of analysis code where provided in analysis specifications. Further details are available at the URL below.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No