Glucagon-like peptide-1 Glucagon-like peptide-1 ( GLP-1 ) is a 30- or 31-amino-acid-long peptide hormone deriving from tissue-specific posttranslational processing of the proglucagon peptide
Unlike many single-pathway peptides, GHK-Cu has been observed to interact with multiple biological systems simultaneously collagen regulation, oxidative stress response, immune modulation, and neural regeneration making it a high-value compound for multi-pathway research protocols
10.1016/0891-5849(93)90139-l 138 SomogyiA.RostaK.PusztaiP.TulassayZ.NagyG
Biased Agonism: Does It Work?# The Evidence So Far# Two drugs in this comparison -- ecnoglutide and CT-388 -- were specifically engineered with biased agonism to improve tolerability: Ecnoglutide (cAMP-biased at GLP-1R): Discontinuation due to AEs: approximately 2%, among the lowest reported for any GLP-1 agonist Weight loss of 13.2% at 40 weeks is competitive with semaglutide-class efficacy The tolerability-to-efficacy ratio appears favorable CT-388 (signal-biased at both GLP-1R and GIPR): Despite very high Phase 1b GI rates during titration (83% nausea), Phase 2 showed only 5.9% AE discontinuation Weight loss of 22.5% at 48 weeks is among the highest in the field The tolerability-to-efficacy ratio is notable: comparable weight loss to tirzepatide with a lower discontinuation rate What the Data Suggest# The biased agonism hypothesis appears to be supported by early clinical data, though with important caveats: Biased agonists do not eliminate GI side effects -- they may reduce their severity and duration The key metric is discontinuation, not incidence -- a drug with high nausea rates but low discontinuation may indicate transient, manageable symptoms Longer and larger trials are needed -- both ecnoglutide and CT-388 have limited Phase 3 data available Patterns and Insights# More Receptors, More Side Effects# A general pattern emerges: adding receptor targets increases both efficacy and GI side effect burden
