Generalized Myasthenia GravisPhase 2THYMENCT06987539
A Study to Evaluate the Pharmacokinetics, Pharmacodynamics, Safety and Tolerability of Inebilizumab in Children With Generalized Myasthenia Gravis (gMG)
A Phase 2 study testing Inebilizumab in people with Generalized Myasthenia Gravis, run by Amgen at 14 sites in 8 countries.
Trial summary
The primary objectives of this study are to characterize the pharmacokinetics (PK) and pharmacodynamics (PD) of inebilizumab administered in pediatric participants with gMG, and to assess the safety and tolerability of inebilizumab administered in pediatric participants with gMG. Read more about this study
- Who is it for?
- Ages 2 to 17 years
- Conditions the study is for
- Generalized Myasthenia Gravis
- What is being tested?
- Inebilizumab
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 15 participants
- Where
- 14 sitesin 8 countries
- Study dates
- 21 Jul 2026to 13 Mar 2030
- Phase
- Phase 2
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 2 to 17 years
- All sexes
- No healthy volunteers
- Child
Who may be able to join
- Participant's legally authorized representative has provided informed consent when the participant is legally too young to provide informed consent and the participant has provided written assent based on local regulations and/or guidelines before any study-specific activities/procedures being initiated.
- Age ≥ 2 to < 18 years of age on the day of enrollment.
- Diagnosis of gMG defined as:
- Positive serologic test for anti-acetylcholine receptor (AChR) or anti-muscle-specific tyrosine kinase (MuSK) antibody (Ab) titers as confirmed at screening (1 retest allowed), and
- At least 1 of the following:
- History of abnormal neuromuscular transmission test results demonstrated by single-fiber electromyography or repetitive nerve stimulation; or
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- History of positive anticholinesterase test (eg, edrophonium chloride test); or
- Participant demonstrated improvement in gMG signs on oral cholinesterase inhibitors, as assessed by the treating physician; or
- Clinical syndrome consistent with a diagnosis of gMG, and not otherwise explained by another condition.
- Myasthenia Gravis Foundation of America Clinical Classification Class II, III, or IV at the time of screening.
- Participants must be on:
- Corticosteroids only, with no dose increase within 4 weeks prior to screening, or
- One allowed non-steroidal immunosuppressive therapies (IST), (azathioprine, mycophenolate mofetil, or mycophenolic acid) with continuous use for at least 6 months prior to screening and no dose increase within 4 months prior to screening, or
- Combination of (1) corticosteroids with no dose increase within 4 weeks prior to screening and (2) one allowed non-steroidal IST with continuous use for at least 6 months prior to screening and no dose increase within 4 months prior to screening.
- Note:
- The maximum allowed dose of prednisone at the time of enrollment will be 40 mg/day or 80 mg every other day, or equivalent corticosteroid dose.
- Tacrolimus is allowed in Japan only, with continued use for ≥ 6 months prior to screening and no dose increase within 4 months prior to screening.
- Participants may enter the study on a stable dose of acetylcholinesterase inhibitors (pyridostigmine dose). The acetylcholinesterase inhibitor dose must have been stable for at least 2 weeks prior to enrollment.
- Vital signs and laboratory parameters within the normal ranges at screening, or, if outside normal ranges, deemed not clinically significant by the investigator.
Who cannot join
- Employees of the Sponsor, contract research organization (CRO), site staff, and their family members.
- Thymectomy within 12 months prior to baseline (Day 1) visit or planned thymectomy during the duration of the treatment period.
- Unresected thymoma- Participants with benign thymoma resected > 12 months prior to screening may enroll.
- History of recurrent significant infections.
- Known immunodeficiency disorder, including current infection or positive test for human immunodeficiency virus (HIV).
- Positive test for chronic hepatitis B infection at screening.
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- History of untreated hepatitis C infection, or positive antibody test for hepatitis C virus (HCV).
- Active tuberculosis (TB); latent TB with no documented history of adequate treatment per local standard of care; or a positive QuantiFERON®-TB test at screening, unless treatment for TB was completed per local guidelines.
- History of progressive multifocal leukoencephalopathy.
- Participants diagnosed with congenital myasthenic syndromes.
- Receipt of any biologic B-cell-depleting therapy (eg, rituximab, ocrelizumab, obinutuzumab, ofatumumab, inebilizumab) or any experimental B-cell-depleting agent in the 6 months prior to screening.
- Receipt of any other monoclonal antibody (mAb) or large molecule biologic, including but not limited to FcRn inhibitors, anti-TNF mAbs, anti-janus kinase (JAK) Stat mAbs, and complement inhibitors within 6 months prior to screening.
- Receipt of the following medications or treatments at any time prior to enrollment: alemtuzumab, total lymphoid irradiation, bone marrow transplant, T-cell vaccination therapy, natalizumab.
- Participants who are pregnant or breastfeeding or planning to get pregnant.
- Receipt of intravenous immunoglobulin (IVIg) or subcutaneous immunoglobulin (SCIg) within 4 weeks prior to enrollment.
Trial locations and contacts
14 sites in 8 countries. Contact the study team or a site near you to ask about taking part.
14 sites in 8 countries
United States4 sites, 4 recruiting
- Recruiting
Austin Neuromuscular Center
Austin, Texas, 78759
- Recruiting
Ann and Robert H Lurie Childrens Hospital of Chicago
Chicago, Illinois, 60611
- Recruiting
The Childrens Hospital of Philadelphia
Philadelphia, Pennsylvania, 19104
- Recruiting
Seattle Childrens Hospital
Seattle, Washington, 98105
Argentina2 sites, 2 recruiting
- Recruiting
Hospital Italiano de Buenos Aires
CABA, Buenos Aires, C1199ABB
- Recruiting
Hospital Britanico de Buenos Aires
CABA, Buenos Aires, C1280AEB
Brazil2 sites, 2 recruiting
- Recruiting
Hospital Santa Izabel
Salvador, Estado de Bahia, 40050-410
- Recruiting
Instituto da Crianca - Hospital das Clinicas Fmusp
São Paulo, São Paulo, 05403-000
Poland2 sites, 2 recruiting
- Recruiting
Medicover Integrated Clinical Services Spolka Z Ograniczona Odpowiedzialnoscia
Bydgoszcz, 85-065
- Recruiting
Lech Szczechowski Wielospecjalistyczna Poradnia Lekarska Synapsis
Katowice, 40-123
France1 site, 1 recruiting
- Recruiting
Hopital Armand Trousseau
Le Kremlin-Bicêtre, 94275
Italy1 site, 1 recruiting
- Recruiting
Azienda Ospedaliera Universitaria Meyer
Florence, 50139
Spain1 site, 1 recruiting
- Recruiting
Hospital Universitari i Politecnic La Fe
Valencia, 46026
United Kingdom1 site, 1 recruiting
- Recruiting
John Radcliffe Hospital
Oxford, OX3 9DU
About this study
Official title: A Phase 2 Open-label Multicenter Study to Evaluate the Pharmacokinetics, Pharmacodynamics, Safety and Tolerability of Inebilizumab in Children From 2 Years to Less Than 18 Years of Age With Generalized Myasthenia Gravis (gMG)
The primary objectives of this study are to characterize the pharmacokinetics (PK) and pharmacodynamics (PD) of inebilizumab administered in pediatric participants with gMG, and to assess the safety and tolerability of inebilizumab administered in pediatric participants with gMG.
- Conditions
- Generalized Myasthenia Gravis
- Being tested
- Inebilizumab
- Keywords
- Generalized Myasthenia Gravis, Inebilizumab, AMG 335, Uplizna
- Medical subject headings
- Myasthenia Gravis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
InebilizumabDrug
Inebilizumab will be administered IV.
| Study group | Role | What they receive |
|---|---|---|
| Inebilizumab | Experimental | Inebilizumab will be administered intravenously (IV). Receives: Drug: Inebilizumab |
What is being measured
The primary outcome is the main question the study is designed to answer.
Maximum Observed Concentration (Cmax) of Inebilizumab
Measured: Up to Week 52
Area Under the Concentration-time Curve (AUC) of Inebilizumab
Measured: Up to Week 52
Half-life (t1/2) of Inebilizumab
Measured: Up to Week 52
Clearance (CL) of Inebilizumab
Measured: Up to Week 52
Volume of Distribution at Steady State (Vss) of Inebilizumab
Measured: Up to Week 52
Change from Baseline in Cluster of Differentiation 20 (CD20)+ B-cell Counts
Measured: Baseline and Week 78
Number of Participants Experiencing Treatment-emergent Adverse Events
Measured: Up to Week 78
Number of Participants Experiencing Clinically Significant Changes in Laboratory Parameters
Measured: Up to Week 78
Number of Participants Experiencing Clinically Significant Changes in Vital Signs
Measured: Up to Week 78
Secondary outcomes (5)
Change from Baseline in Quantitative Myasthenia Gravis (QMG) Score
Measured: Baseline and Week 78
Change from Baseline in Myasthenia Gravis Activities of Daily Living (MG-ADL) Score
Measured: Baseline and Week 78
Change from Baseline in Euro Quality of Life-5 Dimension Youth (EQ-5D-Y) Score
Measured: Baseline and Week 78
Change from Baseline in Neurological Quality of Life (Neuro-QoL) Pediatric Fatigue Score
Measured: Baseline and Week 78
Number of Participants with Anti-drug Antibodies (ADAs) Present
Measured: Up to Week 78
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 May 2025
- Study start21 Jul 2026
- Primary completion13 Mar 2030 (estimated)
- Study completion13 Mar 2030 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Generalized Myasthenia GravisStudies of the same condition, open and under way.
- More trials run by AmgenThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 15 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Amgen
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- MD, Study director, Amgen
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06987539
- Sponsor's protocol ID
- 20240236
- Other IDs
- 2025-520993-20, 2025
- Acronym
- THYME
- Status last verified
- Oct 2026
- First submitted
- 16 May 2025
- Last updated
- 23 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: De-identified individual patient data for variables necessary to address the specific research question in an approved data sharing request.