Efficacy and Safety of Bimagrumab/BYM338 at 52 Weeks on Physical Function, Muscle Strength, Mobility in sIBM Patients

A randomized, double-blind, placebo-controlled, multicenter, parallel group, dose-finding, pivotal, phase IIb/III study to evaluate the efficacy, safety and tolerability of intravenous BYM338 at 52 weeks on physical function, muscle strength, and mobility and additional long-term safety up to 2 years in patients with sporadic inclusion body myositis

Status

Unknown

Phases

Phase 3

Study type

Interventional

Source

JPRN

Registry ID

JPRN-jRCT2080222316

Enrollment

240

Registered

2013-12-03

Start date

2013-12-03

Completion date

Unknown

Last updated

2026-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Sporadic Inclusion Body Myositis

Interventions

investigational material(s) Generic name etc : BYM338 INN of investigational material : Bimagrumab Therapeutic category code : 399 Agents affecting metabolism, n.e.c. Dosage and Administration for In

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: Diagnosed with sporadic inclusion body myositis; Must be able to walk (assistive aids allowed, including intermittent use of wheelchair)

Exclusion criteria

Exclusion criteria: Must not be using corticosteroids. Must not have used systemic corticosteroid (at daily dose >=10mg prednisone) for the past 3 months; Must not be pregnant or nursing; Must not have a chronic active infection (e.g., HIV, hepatitis B or C, tuberculosis, etc); Other protocol-defined inclusion/exclusion criteria may apply -Any non-sIBM conditions or other neurologic, neuromuscular diseases that significantly limit mobility (polymyositis, dermatomyositis, polymyalgia rheumatica, fibromyalgia, significant dementia/Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, stroke, cerebral palsy, epilepsy, multiple sclerosis, spinal cord injury, muscular dystrophy, myasthenia gravis, ). -Significant cardiovascular diseases. -Ongoing immunosuppressive therapy (antibody therapy within past 6 months or non-antibody therapy within past 3months prior to randomization).

Design outcomes

Primary

Measure	Time frame
Change from Baseline in 6 Minute Walking Distance Test (6MWD) meters to Week 52 [ Time Frame: Baseline, Week 52 ] Change from baseline to Week 52 in the distance a patient can walk in a set timeframe. 6 Minute Walking Distance Test measures the distance (in meters) that a patient can walk in a 6 minute timeframe.	—

Secondary

Measure	Time frame
Change from Baseline in lean body mass (LBM) at Week 52 [ Time Frame: Baseline, Week 52 ] Change from baseline to Week 52 in the total and appendicular lean body mass Change from Baseline in quadriceps Quantitative Muscle Testing (QMT) at Week 52 [ Time Frame: Baseline, Week 52 ] Change from baseline to Week 52 in quadriceps QMT. Change from Baseline in Patient-Reported Physical Function at Week 52 [ Time Frame: Baseline, Week 52 ] Change from baseline to Week 52 in a patient reported outcome instrument. Rate of Fall Events [ Time Frame: Baseline, Day 1, Weeks 2, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 76, 80, 84, 88, 92, 96, 100, 104, 108 ] Number of falls Change from Baseline in Short Physical Performance Battery score at Week 52 [ Time Frame: Baseline, Week 52 ] Change from baseline to Week 52 in physical performance as measured by the Short Physical Performance Battery (SPPB). Safety and Tolerability of different i.v. BYM338 doses [ Time Frame: Baseline, Day 1, Weeks 2, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 76, 80, 84, 88, 92, 96, 100, 104, 108 ] Safety and tolerability Change from Baseline in 6MWD meters to Week 52 [ Time Frame: Baseline, Week 52 ] Dose-response relationship	—

Measure

Time frame

Change from Baseline in lean body mass (LBM) at Week 52 [ Time Frame: Baseline, Week 52 ] Change from baseline to Week 52 in the total and appendicular lean body mass Change from Baseline in quadriceps Quantitative Muscle Testing (QMT) at Week 52 [ Time Frame: Baseline, Week 52 ] Change from baseline to Week 52 in quadriceps QMT. Change from Baseline in Patient-Reported Physical Function at Week 52 [ Time Frame: Baseline, Week 52 ] Change from baseline to Week 52 in a patient reported outcome instrument. Rate of Fall Events [ Time Frame: Baseline, Day 1, Weeks 2, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 76, 80, 84, 88, 92, 96, 100, 104, 108 ] Number of falls Change from Baseline in Short Physical Performance Battery score at Week 52 [ Time Frame: Baseline, Week 52 ] Change from baseline to Week 52 in physical performance as measured by the Short Physical Performance Battery (SPPB). Safety and Tolerability of different i.v. BYM338 doses [ Time Frame: Baseline, Day 1, Weeks 2, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 76, 80, 84, 88, 92, 96, 100, 104, 108 ] Safety and tolerability Change from Baseline in 6MWD meters to Week 52 [ Time Frame: Baseline, Week 52 ] Dose-response relationship

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Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Jul 3, 2026