Bimagrumab (BYM338): dosing
> Updated:
Human schedule
Bimagrumab (BYM338) is a monoclonal antibody that in clinical studies was given mainly by intravenous infusion. The table below is a generalized reference to regimens described in phase I–II studies.
This is a concise reference to regimens described for adults; it is not an individual prescription.
Bimagrumab (BYM338) dosing is always tied to an intravenous infusion at a clinical site on a fixed visit schedule every 4 weeks, unlike subcutaneous peptides that a person injects themselves; that structure is what shapes the schedule below.
| Period / condition | Dose | Escalation |
|---|---|---|
| Early studies (phase I) | 210–700 mg IV every 4 weeks | Starting dose |
| Main phase II regimen | 10 mg/kg (max 1200 mg) IV every 4 weeks | Increase if needed |
| Later studies | 10–30 mg/kg IV every 12 weeks | Maximum in this schedule |
Practical dosage and effect notes
In a trial by Heymsfield and colleagues (JAMA Network Open, 2021), adults with obesity and type 2 diabetes received bimagrumab on exactly the table's "Main phase II regimen": 10 mg/kg (max 1200 mg) intravenously every 4 weeks, 12 infusions over 48 weeks. Body fat mass fell by 20.5% on average (minus 7.49 kg) versus 0.5% with placebo, while lean mass rose 3.6% (plus 1.70 kg), against a 0.8% decline with placebo.
That is why bimagrumab's dose is scaled to body weight (mg/kg) rather than fixed as a flat number the way most peptides are: the same 10 mg/kg dose delivers a different milligram amount to a 60 kg person than a 100 kg one. The infrequent dosing, every 4–12 weeks, reflects the monoclonal antibody's long half-life, not a chosen interval.
This is background for planning a research protocol, not a medical recommendation and not instructions for self-administration.
This reference is research-use material. The information is not medical advice and is not intended for diagnosis, treatment or prevention of disease.