Bimagrumab

Dosing from the Literature

Published for fat loss: trial doses by IV infusion: 10 mg/kg every 4 weeks, or 10 or 30 mg/kg every 12 weeks after two loading doses, for 48 weeks. Not published: an approved dose, or any obesity result from the under-the-skin dosing Lilly now tests.

No dose of bimagrumab is approved. The rows are trial doses and one registered regimen, as the documents give them; they are not recommendations. Most trials dosed by body weight: at 30 mg/kg, a 100 kg adult receives 3,000 mg in one infusion. Lilly’s registry entries for its under-the-skin trials give no amounts; its Phase 2 names them only “Dose 1” and “Dose 2” (ClinicalTrials.gov NCT06643728).

What It Is

Bimagrumab is “a fully human monoclonal antibody” (Hanna et al., 2019) against the activin type II receptors. FDA’s substance registry records it as an IgG1 lambda antibody made of four protein chains, two of 445 amino acids and two of 217, with a calculated mass of about 143,000 daltons (GSRS, UNII N15SW1DIV8). It is not a peptide. Novartis developed it under the code BYM338 and described it in 2014 as “a novel, human anti-ActRII antibody” (Lach-Trifilieff et al., 2014).

Novartis’s trials started in 2011, in people losing muscle: inclusion body myositis, sarcopenia, recovery after hip fracture, COPD and cancer cachexia (ClinicalTrials.gov). From 2017 to 2019 it ran a 48-week trial in adults with type 2 diabetes and obesity (Heymsfield et al., 2021). Versanis Bio, which Aditum Bio founded in 2021, then made bimagrumab its lead asset and took it into BELIEVE, an obesity trial alone and with semaglutide. Eli Lilly agreed to buy Versanis on July 14, 2023, for up to $1.925 billion in cash, and completed the purchase on August 14, 2023 (Lilly press releases). In Lilly’s trials the drug is LY3985863, and one completed Phase 1 study tested it coformulated with tirzepatide (ClinicalTrials.gov NCT06890611).

On September 29, 2026, PubMed returned 79 records naming bimagrumab or BYM338 in the title or abstract, 17 of them indexed as clinical trials. ClinicalTrials.gov lists 18 bimagrumab studies: 14 completed, 2 withdrawn before enrolling anyone, 1 active but no longer recruiting and 1 recruiting. Searches of FDA’s Drugs@FDA data and of DailyMed found no approved product.

Mechanism of Action

Receptor and pathway names below are the cited papers’ own.

• ActRIIA and ActRIIB (the target) — In crystal structures, bimagrumab binds the ligand-binding domains of both activin type II receptors “in a competitive manner at the critical myostatin/activin binding site,” with picomolar affinity (Morvan et al., 2017).
• Both receptors, not one — In cells, antibodies against one receptor cut myostatin and activin A signaling by only 30–50%. In mice, single-receptor antibodies raised body weight about 10%, against 16–22% with bimagrumab; the authors conclude that full neutralization needs both receptors blocked (Morvan et al., 2017).
• Myostatin, GDF11 and activins → Smad2/3 (the brake) — Myostatin, GDF11 and the activins signal through these receptors. Bimagrumab prevented myostatin- or activin A-induced atrophy by blocking Smad2/3 phosphorylation, and enhanced differentiation of primary human skeletal myoblasts (Lach-Trifilieff et al., 2014).
• ALK4 in muscle, ALK7 in fat — The BELIEVE authors describe two routes: myostatin and activin A signaling via ActRII and ALK4 in muscle, and activin signaling via ActRII and ALK7 in adipose tissue, which human exome studies of the INHBE gene (activin E) and the ACVR1C gene (ALK7) link to abdominal obesity. They write that by blocking ligand signaling in fat, bimagrumab increases lipid mobilization and lipolysis (Heymsfield et al., 2026).
• Food intake (apparently unaffected) — The same authors write that bimagrumab “does not appear to affect food intake.” At week 24, median daily intake fell 182.0 kcal on bimagrumab 30 mg/kg, 482.5 kcal on semaglutide 2.4 mg and 238.5 kcal on placebo (Heymsfield et al., 2026).
• Activin and FSH (the pituitary) — Activins also act on the pituitary. In healthy adults aged 55–75 given 10 mg/kg twice, FSH fell 42.16 IU/L more than on placebo in women at week 8; the effect reversed once the drug cleared, and gonadal and adrenal androgens were unaffected (Garito, Zakaria et al., 2018).
• Ligand build-up — Blocking both receptors raised circulating activin A in mice while muscle expression of its gene stayed unchanged, which the authors attribute to ligand no longer being taken up and degraded (Morvan et al., 2017).
• Pharmacokinetics — Blood levels are non-linear, which the authors attribute to target-mediated drug disposition (Rooks, Petricoul et al., 2020). About 40% of an under-the-skin dose reaches the blood, and weekly injections gave levels and effects comparable to monthly infusions (Petricoul et al., 2023). No half-life figure appears in the documents read for this page.

What the Research Shows

Animal work first, then the two meta-analyses of the human trials; each trial is under Human Data.

• Muscle in mice — Bimagrumab increased skeletal muscle mass beyond what a myostatin inhibitor achieved, and protected mice from glucocorticoid-induced atrophy and weakness (Lach-Trifilieff et al., 2014). In mice given four weeks of weekly injections, hind-limb muscles were 18–38% heavier (Morvan et al., 2017).
• Fat in animals, then in people — The 2021 trial report says preclinical studies in several species found no reduction of white fat, “indicating that this pathway behaves differently in humans” (Heymsfield et al., 2021). A later study in diet-induced obese mice did find fat loss: about 10% more lean mass with less fat mass, and with semaglutide, more fat loss than semaglutide alone while lean mass was preserved (Nunn et al., 2024).
• Cancer cachexia in mice — A mouse version of the antibody, CDD866, protected against muscle loss in a colon-cancer model, alongside cisplatin or everolimus; both combinations slowed time to progression (Hatakeyama et al., 2016).
• Bone healing in rats — In 150 rats with a cut fibula, bimagrumab had no major effect on fracture healing; young rats had a slightly smaller immature callus at day 29 (Tankó et al., 2016).
• Muscle in people — A meta-analysis of seven randomized trials in sarcopenia found thigh muscle volume up 5.29%, fat-free mass up 1.90 kg and fat mass down 4.55 kg against placebo, with no significant gain in strength, gait speed or 6-minute walk except in slower walkers (Kanbay et al., 2024).
• Fat in people — A meta-analysis of four randomized trials in 268 adults with obesity, insulin resistance or type 2 diabetes found weight down 4.85 kg, fat mass down 4.72 kg, lean mass up 1.66 kg and HbA1c down 0.13% against placebo, with LDL cholesterol up 0.47 mmol/L and more discontinuations (risk ratio 5.75), muscle spasms (10.44) and diarrhoea (4.91) (Shao et al., 2026).

Human Data

PubMed indexes 17 trial reports (September 29, 2026). By use:

• Insulin resistance, one dose (Garito, Roubenoff et al., 2018) — 16 people with a mean BMI of 29.3. At week 10, lean mass rose 2.7% and fat mass fell 7.9% against placebo, with body weight unchanged; HbA1c fell 0.21% at week 18, and insulin sensitivity improved by about 20% (clamp) to 40% (intravenous glucose tolerance test).
• Type 2 diabetes with obesity, 48 weeks (Heymsfield et al., 2021; NCT03005288) — 75 adults at 9 US and UK sites; 58 completed. Against placebo: fat mass −20.5% (−7.5 kg) vs −0.5%, lean mass +3.6% (1.70 kg) vs −0.8%, body weight −6.5% (−5.9 kg) vs −0.8%, waist −9.0 cm vs +0.5 cm, HbA1c −0.76 vs +0.04 percentage points (as corrected in 2021). Only participants who completed a full treatment regimen were analyzed, and the trial used a one-sided 10% significance level, which the authors say reflected the sponsor’s “willingness to accept a liberal standard of evidence.”
• BELIEVE, obesity, 72 weeks (Heymsfield et al., 2026; NCT05616013) — 507 adults without diabetes at 26 sites in the United States, Australia and New Zealand, in nine groups; 377 (74.4%) completed week 48. Weight change at 48 weeks: −3.3 kg on placebo; −6.0 kg on bimagrumab 10 mg/kg (not significantly different from placebo, p = 0.133) and −9.3 kg on 30 mg/kg; −9.8 and −14.2 kg on semaglutide 1.0 and 2.4 mg; −12.7 to −17.8 kg on the combinations. Lean mass changed +1.0% to +1.1% on bimagrumab alone, −4.7% to −6.9% on semaglutide alone and −0.8% to −2.3% on the combinations. At 72 weeks, in a post hoc analysis, weight was down 10.8% on bimagrumab 30 mg/kg, 15.7% on semaglutide 2.4 mg and 22.1% on the two together at those doses. Semaglutide was open-label, P values were nominal, and the authors write that without multiplicity adjustment “these results should not be used to infer definitive treatment effects.” Lilly funded the study, with Versanis funding part of it before the acquisition; Versanis designed and oversaw it.
• Heart, 6 months (Rooks et al., 2026) — 68 healthy adults aged 60–86 at one commercial site: no clinically relevant change in left ventricular mass or ejection fraction on cardiac MRI; lean mass +5.5% and fat mass −14% against placebo.
• Dosing studies — Single infusions in 16 older adults and 8 adults with obesity (Rooks, Petricoul et al., 2020); infusions against under-the-skin doses in 91 adults aged 70 or older, in whom lean mass rose 4–6% except on the lowest dose (Petricoul et al., 2023).
• Inclusion body myositis — In 14 patients given one dose of bimagrumab (11) or placebo (3), right thigh muscle volume rose 6.5% against placebo at 8 weeks, and 6-minute walk distance 14.6% at 16 weeks (Amato et al., 2014). RESILIENT, 251 patients at 38 sites: 6-minute walk distance at week 52 did not differ from placebo at any dose (Hanna et al., 2019); in its extension (211 patients), walking declined in every group through week 104 and the study was stopped early (Amato et al., 2021). An open-label extension after a single-dose study (10 patients, up to 2 years) found lean mass up and “no evidence of clinical improvement” (Sivakumar et al., 2020).
• Sarcopenia — In 40 adults aged 65 or older, thigh muscle volume rose 8.01% vs 0.35% at week 8; slower walkers gained 0.15 m/s of gait speed and 82 m of 6-minute walk more than on placebo at week 16 (Rooks, Praestgaard et al., 2017). In 180 adults aged 70 or older on diet and home exercise, lean mass rose 7% vs 1%, but physical performance scores (+1.34 vs +1.03, P = .13) and walk distance (P = .16) did not differ (Rooks, Swan et al., 2020).
• Hip fracture — 250 adults aged 60 or older: lean mass +1.9 kg on 210 mg and +2.8 kg on 700 mg against +0.2 kg on placebo, with no difference in gait speed or physical performance (Hofbauer et al., 2021).
• COPD and disuse — In 67 people with COPD, thigh muscle volume was +5.0% vs −1.3% at week 24, and walk distance did not rise significantly in either group (Polkey et al., 2019). In 24 young men after 2 weeks in a leg cast, thigh muscle volume was 5.1% above its pre-cast level at week 12 vs −0.1% on placebo; strength recovered in both groups within 6 weeks (Rooks, Laurent et al., 2017).
• Unpublished — A Novartis trial in 57 people with advanced lung or pancreatic cancer (NCT01433263) posted results on ClinicalTrials.gov; no paper on it was found in PubMed. Lilly’s trials with tirzepatide (NCT06643728, 252 adults; NCT06890611) and in healthy Chinese adults (NCT07030127) list no posted results, and its Phase 2b in type 2 diabetes (NCT06901349) was withdrawn before enrolling anyone, “for strategic business reasons.”

The evidence meter on the bimagrumab card reads “Human trials”: it counts published controlled trials for fat loss, the use on its tag. None has led to an approval.

Reconstitution & Storage

There is nothing to reconstitute in the documents. In Novartis’s inclusion body myositis trials, bimagrumab was “a 150 mg/mL concentrate for solution for i.v. infusion,” supplied in glass vials (ClinicalTrials.gov NCT01925209). Trial sites gave it as an intravenous infusion: in 5% dextrose solution (Heymsfield et al., 2021), over 30 minutes (Heymsfield et al., 2026) or over 2 hours (Rooks, Petricoul et al., 2020). Lilly’s current trials give it under the skin; their registry entries don’t describe that formulation.

• Dose sizes — Trial doses included 52.5 mg a week under the skin and 1,500 mg by subcutaneous infusion (Petricoul et al., 2023), and infusions of 30 mg/kg (Heymsfield et al., 2026), which is 3,000 mg for a 100 kg adult.
• Storage — No document read for this page gives storage conditions for the trial material. The two laboratory-reagent listings read give −20°C for their research-grade copies, which they label for research use only.

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Side Effects & Risks

• Muscle spasms — The most common adverse event on bimagrumab alone in BELIEVE: 46.4% on 10 mg/kg and 73.7% on 30 mg/kg, against 5.5% on placebo; they ended treatment for five people, all on bimagrumab alone (Heymsfield et al., 2026). 41% vs 3% in the 2021 diabetes trial (Heymsfield et al., 2021); 57.1% vs 6.1% in healthy older adults (Rooks et al., 2026); 40–68% vs 21% in RESILIENT (Hanna et al., 2019).
• Diarrhea — 41.1% and 49.1% vs 5.5% in BELIEVE (Heymsfield et al., 2026); 41% vs 11%, most often after the first dose, in the 2021 trial (Heymsfield et al., 2021); 32–52% vs 18% in RESILIENT (Hanna et al., 2019).
• Acne — 33.9% and 43.9% vs 3.6% in BELIEVE, where four people stopped treatment for it (Heymsfield et al., 2026); 14.3% vs 0% in healthy older adults (Rooks et al., 2026).
• Stopping treatment — In BELIEVE, adverse events ended treatment for 21.4% (10 mg/kg) and 14.0% (30 mg/kg) on bimagrumab alone, against 3.6% on placebo; serious adverse events were 12.5% and 8.8% against 3.6%, and no one died (Heymsfield et al., 2026). A 2026 meta-analysis put the risk ratio for discontinuation at 5.75 (Shao et al., 2026).
• Pancreas — BELIEVE had three serious pancreatitis events: one each on placebo, bimagrumab 10 mg/kg and semaglutide 1.0 mg. Lipase rose transiently with bimagrumab (Heymsfield et al., 2026). In the 2021 trial one participant on bimagrumab was hospitalized with pancreatitis (Heymsfield et al., 2021).
• Cholesterol — LDL cholesterol rose in the first 12 weeks on bimagrumab. At week 72 it was 17.6% above baseline on 30 mg/kg alone and +0.1% on 30 mg/kg with semaglutide 2.4 mg (Heymsfield et al., 2026). The 2026 meta-analysis found LDL 0.47 mmol/L higher than on placebo (Shao et al., 2026).
• Heart — The cardiac-safety study’s authors note that in preclinical studies “an increase in cardiac size and weight accompanied the large gain in skeletal muscle mass and was reversible with drug withdrawal”; in their 68 healthy older adults, six months of 10 mg/kg a month brought no clinically relevant change in left ventricular mass or ejection fraction on cardiac MRI (Rooks et al., 2026). RESILIENT recorded no significant adverse cardiac effects on electrocardiography or echocardiography (Hanna et al., 2019).
• Bone — In BELIEVE, total-hip bone density fell significantly more than on placebo (−0.8%) with semaglutide 2.4 mg (−2.1%) and three combination groups (−2.0% to −2.3%); on bimagrumab alone it fell 1.1% and 1.5% (Heymsfield et al., 2026). A rat study found no major effect on fracture healing (Tankó et al., 2016).
• Skin cancers — Through week 48, four BELIEVE participants reported basal or squamous cell skin carcinoma, two on bimagrumab alone and two on semaglutide 2.4 mg alone; in the open-label extension, two participants reported basal cell skin carcinoma, in the bimagrumab 30 mg/kg and semaglutide 1.0 mg groups (Heymsfield et al., 2026).
• Cancer cachexia (registry results only) — In 57 people with advanced lung or pancreatic cancer, serious adverse events were posted for 18 of 29 on bimagrumab 30 mg/kg and 4 of 28 on placebo during the core period, most often “malignant neoplasm progression” (6 vs 0). The posted results don’t say whether any event was caused by the drug (ClinicalTrials.gov NCT01433263).
• Antibodies against the drug — Two participants in the 2021 trial developed non-neutralizing anti-drug antibodies that didn’t change exposure (Heymsfield et al., 2021); the 2026 cardiac study reported no immunogenicity signal (Rooks et al., 2026).
• Pregnancy — BELIEVE required women who could become pregnant to use an intrauterine device and a barrier method through at least 4 months after the last bimagrumab dose (Heymsfield et al., 2026).
• WADA prohibited — Named under S4.3, prohibited at all times. Anti-doping researchers have validated a method that detects bimagrumab in serum (Walpurgis et al., 2018).
• Identity and purity — The only copies outside trials documented here are laboratory reagents labelled for research use only. No document read for this page tests them or compares them with the trial material.
• Drug interactions — The only combination with published results is semaglutide, in BELIEVE (Heymsfield et al., 2026). Lilly’s Phase 1 study measuring blood levels of bimagrumab and tirzepatide given together (NCT06890611) and its Phase 2 with tirzepatide (NCT06643728) have no posted results.

Bloodwork & Monitoring

No document read for this page gives monitoring guidance for bimagrumab outside trial protocols. What the trials measured, and what changed:

• Lipids — Total and LDL cholesterol rose in the first 12 weeks on bimagrumab (Heymsfield et al., 2026).
• Liver and muscle enzymes — Alkaline phosphatase and creatine kinase rose, ALT and AST rose transiently, and bilirubin and GGT fell (Heymsfield et al., 2026). In the cardiac study, mean creatine kinase at 6 months was 3.7 µkat/L on bimagrumab and 1.4 on placebo (Rooks et al., 2026).
• Lipase and amylase — Early, transient rises (Heymsfield et al., 2021; Heymsfield et al., 2026).
• Magnesium — Mean levels fell on bimagrumab but stayed in the normal range (Heymsfield et al., 2026).
• FSH, LH and urate — In women, FSH fell 42.16 IU/L more than on placebo at week 8 and LH rose 2.5 IU/L (P = .08), both reversible (Garito, Zakaria et al., 2018). FSH and urate fell in the 2021 trial (Heymsfield et al., 2021).
• Heart — The trials used electrocardiography and echocardiography (Hanna et al., 2019), and cardiac MRI, CK-MB and NT-proBNP (Rooks et al., 2026).
• Body composition — DXA for fat and lean mass, and MRI for thigh muscle, in the trials above.
• Which tests fit a given person — A question for a licensed healthcare provider. This page can’t answer it.

Commonly Stacked With

Two combinations have been tested in trials: semaglutide in BELIEVE, and tirzepatide in Lilly’s trials; a hospital trial of the tirzepatide combination is recruiting. No document read for this page shows people combining bimagrumab with anything outside a trial.

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Legal Status

Related Compounds

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Next Steps

References

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11. Polkey MI, Praestgaard J, Berwick A, et al. Activin Type II Receptor Blockade for Treatment of Muscle Depletion in Chronic Obstructive Pulmonary Disease. A Randomized Trial. Am J Respir Crit Care Med. 2019;199(3):313-320. PMID: 30095981.
12. Garito T, Roubenoff R, Hompesch M, et al. Bimagrumab improves body composition and insulin sensitivity in insulin-resistant individuals. Diabetes Obes Metab. 2018;20(1):94-102. PMID: 28643356.
13. Garito T, Zakaria M, Papanicolaou DA, et al. Effects of bimagrumab, an activin receptor type II inhibitor, on pituitary neurohormonal axes. Clin Endocrinol (Oxf). 2018;88(6):908-919. PMID: 29566437.
14. Heymsfield SB, Coleman LA, Miller R, et al. Effect of Bimagrumab vs Placebo on Body Fat Mass Among Adults With Type 2 Diabetes and Obesity: A Phase 2 Randomized Clinical Trial. JAMA Netw Open. 2021;4(1):e2033457. PMID: 33439265. Errata: JAMA Netw Open. 2021;4(2):e211376 and 2021;4(3):e212581 (the second corrects the placebo group’s HbA1c change to +0.04 points).
15. Rooks D, Petricoul O, Praestgaard J, Bartlett M, Laurent D, Roubenoff R. Safety and pharmacokinetics of bimagrumab in healthy older and obese adults with body composition changes in the older cohort. J Cachexia Sarcopenia Muscle. 2020;11(6):1525-1534. PMID: 33264516.
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17. Heymsfield SB, Aronne LJ, Montgomery P, et al.; BELIEVE trial investigators. Bimagrumab plus semaglutide alone or in combination for the treatment of obesity: a randomized phase 2 trial. Nat Med. 2026;32(3):869-882. PMID: 41772149.
18. Rooks D, Yates DP, Neelakantham S, et al. Cardiac safety of chronic inhibition of the myostatin-activin pathway with bimagrumab in healthy older adults. J Clin Endocrinol Metab. 2026;111(9):2573-2582. PMID: 41873146.
19. Nunn E, Jaiswal N, Gavin M, et al. Antibody blockade of activin type II receptors preserves skeletal muscle mass and enhances fat loss during GLP-1 receptor agonism. Mol Metab. 2024;80:101880. PMID: 38218536.
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21. Tankó LB, Goldhahn J, Varela A, et al. Does Activin Receptor Blockade by Bimagrumab (BYM338) Pose Detrimental Effects on Bone Healing in a Rat Fibula Osteotomy Model? Calcif Tissue Int. 2016;99(3):310-321. PMID: 27167138.
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27. Eli Lilly and Company; Versanis Bio. Lilly to Acquire Versanis to Improve Patient Outcomes in Cardiometabolic Diseases. Press release (PR Newswire), July 14, 2023. prnewswire.com/news-releases/lilly-to-acquire-versanis-to-improve-patient-outcomes-in-cardiometabolic-diseases-301877184.html. Read September 29, 2026.
28. Eli Lilly and Company. Lilly Completes Acquisition of Versanis Bio. Press release (PR Newswire), August 14, 2023. prnewswire.com/news-releases/lilly-completes-acquisition-of-versanis-bio-301899755.html. Read September 29, 2026.
29. PubMed. Search for bimagrumab or BYM338 in title or abstract: 79 records, 17 with clinical-trial publication types. September 29, 2026.
30. ClinicalTrials.gov. Search for “bimagrumab OR BYM338 OR LY3985863”: 18 studies (API v2), September 29, 2026.
31. ClinicalTrials.gov. NCT01925209 and NCT02573467 (RESILIENT and its extension): intervention description, “a 150 mg/mL concentrate for solution for i.v. infusion.” Read September 29, 2026.
32. ClinicalTrials.gov. NCT01433263 (bimagrumab in cachexia with non-small cell lung cancer or pancreatic adenocarcinoma, Novartis): posted results. Read September 29, 2026.
33. ClinicalTrials.gov. NCT06643728, NCT06890611, NCT07030127 and NCT06901349 (Eli Lilly); NCT05933499 (Massachusetts General Hospital). Read September 29, 2026.
34. World Anti-Doping Agency. Prohibited List 2026 (in effect January 1, 2026). S4.3, Agents preventing activin receptor IIB activation. wada-ama.org.
35. FDA. Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act (categories 1–3). Updated May 14, 2026. fda.gov/media/94155/download.
36. 21 CFR 216.23. Bulk drug substances that can be used to compound drug products in accordance with section 503A of the Federal Food, Drug, and Cosmetic Act. ecfr.gov, current as of September 25, 2026.
37. FDA. Drugs@FDA data (api.fda.gov/drug/drugsfda.json) and drug labels (api.fda.gov/drug/label.json), and NLM DailyMed (dailymed.nlm.nih.gov): searches for “bimagrumab,” no records, September 29, 2026.
38. FDA. Orphan Drug Designations and Approvals, record 369012: bimagrumab, designated June 18, 2012, treatment of inclusion body myositis, sponsor Novartis Pharmaceuticals Corp. accessdata.fda.gov/scripts/opdlisting/oopd/. Read September 29, 2026.
39. FDA/NCATS Global Substance Registration System. Bimagrumab, UNII N15SW1DIV8. gsrs.ncats.nih.gov. Read September 29, 2026.
40. Selleck Chemicals. Bimagrumab (Anti-ACVR2B), Cat. No. A2595, product page. selleckchem.com/products/bimagrumab-anti-acvr2b.html. Read September 29, 2026.
41. Thermo Fisher Scientific. ACVR2B (Bimagrumab Biosimilar) Recombinant Human Monoclonal Antibody, Invitrogen MA5-41992, product page. thermofisher.com. Read September 29, 2026.

Related Research

• SemaglutideGLP-1 Receptor Agonist (the drug BELIEVE combined with bimagrumab)
• TirzepatideDual GIP/GLP-1 Receptor Agonist (in Lilly’s bimagrumab trials)
• Follistatin-344Myostatin / Activin-Binding Glycoprotein (same WADA class, S4.3)
• FLGR-242Branded Follistatin Construct (no published study)
• MariTideMaridebart Cafraglutide, Peptide-Antibody Conjugate (obesity, Amgen)