Phase 3 Study to Assess the Efficacy and Safety of Batoclimab as Induction and Maintenance Therapy in Adult Participants With Generalized Myasthenia Gravis

Phase 3Active Not RecruitingNCT05403541

Immunovant Sciences GmbH240 enrolled

Overview

The purpose of this 4-period study is to confirm the efficacy and safety of batoclimab in participants with gMG. In Period 1, participants will be randomized 1:1:1 to receive batoclimab 680 milligrams (mg) subcutaneously (SC) once a week (QW) or 340 mg SC QW or placebo. The primary efficacy endpoint will be assessed by change in the myasthenia gravis activities of daily living (MG- ADL) score in acetylcholine receptor antibody seropositive (AChRAb+) participants. In Period 2, participants previously treated with batoclimab will be re-randomized to stay on batoclimab (340 mg SC QW or 340 mg SC every two weeks) or receive placebo treatment. The secondary endpoint of maintenance of efficacy will be assessed by change in the MG- ADL score in AChRAb+ participants. Participants demonstrating a response to batoclimab during either Period 1 or 2 may enter the long-term extension (Period 3). Participants who complete Period 3 are eligible to participate in Period 4 (Optional Long-Term extension) according to their treatment assignment in Period 3.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

TRIPLE

Enrollment

240

Conditions

Generalized Myasthenia Gravis

Interventions

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: 1. Are ≥ 18 years of age at the Screening Visit. 2. Have mild to severe gMG by Myasthenia Gravis Foundation of America (MGFA) classification Class II, III, or IVa at the Screening Visit. 3. Have a QMG score ≥ 11 at the Screening and Baseline Visits. 4. Have a MG-ADL score of ≥ 5 at the Screening and Baseline Visits. 5. Additional inclusion criteria are defined in the protocol. Exclusion Criteria: 1. Have experienced myasthenic crisis within 3 months of the Screening Visit. 2. Have had a thymectomy performed \< 6 months prior to the Screening Visit or have a planned thymectomy during the study period. 3. Have any active or untreated malignant thymoma. 4. Have received any agent or therapy (exclusive of those identified within inclusion criteria) with immunosuppressive properties (e.g., stem cell therapy, chemotherapies) within the past year. 5. Have used anti-FcRn treatment within 3 months prior to the Screening Visit or have a documented history of non-response to prior anti-FcRn treatment. 6. Additional exclusion criteria are defined in the protocol.

Locations (105)

Site Number -1022

Phoenix, Arizona, United States

Site Number -1029

Scottsdale, Arizona, United States

Site Number -1002

Carlsbad, California, United States

Site Number -1009

Irvine, California, United States

Site Number - 1012

Olive View, California, United States

Site Number -1032

Outcomes

Primary Outcomes

Change from Baseline in Myasthenia Gravis Activities of Daily Living (MG-ADL) score in acetylcholine receptor (AChR) Ab seropositive (AChRAb+) participants

MG-ADL is an 8-item, participant-reported questionnaire that assesses gMG symptoms and their effects on activities of daily living. Each item is assessed on a 4-point scale where a score of 0 represents normal function and a score of 3 represents loss of ability to perform that function. Total score ranges from 0 to 24, with higher scores indicating greater functional impairment and disability.

Time frame: Baseline (Day 1) to Week 12

Secondary Outcomes

Change from Baseline in Quantitative Myasthenia Gravis (QMG) score in AChRAb+ participants

QMG is clinician-reported assessment to evaluate muscle weakness in participants with MG. The QMG consists of 13 items ranging from 0 to 3 with 3 being the most severe. Total score ranges from 0 to 39, with higher scores representing greater impairment.

Time frame: Baseline (Day 1) to Week 12

Change from Baseline in MG-ADL score for AChRAb+ randomized withdrawal participants

Time frame: Baseline (Week 12) to Week 24

Percentage of AChRAb+ participants with greater than equal to (>=) 3-point improvement in QMG score

Time frame: Up to Week 12

Percentage of AChRAb+ participants achieving MG-ADL score of 0 or 1 by Week 12

Time frame: Up to Week 12

Change from Baseline in MG-ADL score in AChRAB- (AChRAB negative) participants

Time frame: Baseline (Day 1) to Week 12

Percentage of Participants with Treatment Emergent Adverse Events (TEAEs)

An adverse event (AE) is defined as any untoward medical occurrence in a participant who has either been administered a study drug or has undergone study procedures.

Time frame: Up to 76 Weeks

Percentage of Participants With Clinically Significant Changes in Vital Sign Measurements

Vital signs, including systolic and diastolic blood pressures, pulse rate, respiratory rate, and temperature will be obtained and recorded at specified timepoints. All vital sign measures will be obtained with the participant in the supine position and having rested for at least 5 minutes.

Time frame: Up to 76 Weeks

Number of Participants with Clinically Significant Changes in Laboratory Results

Blood samples will be collected at specified timepoints for the analysis of laboratory parameters including clinical chemistry, hematology and urinalysis.

Time frame: Up to 76 Weeks

Percentage of participants with clinical laboratory-related TEAEs or treatment emergent laboratory abnormalities.

Time frame: Up to 76 Weeks