Retatrutide

Compound Overview

Retatrutide (development code LY3437943) is a 39-residue synthetic peptide designed for triple agonism at the GIP, GLP-1, and glucagon receptors. Nexus publishes the current-lot chromatogram and mass spectrometry metadata directly on this product page so researchers can review the batch represented by the shipping inventory.

Within incretin-pathway research, retatrutide is differentiated by simultaneous engagement of three G-protein-coupled receptor systems associated with energy intake, energy expenditure, and glucose homeostasis research. Semaglutide is used as a GLP-1-only comparator; Tirzepatide is used as a GIP/GLP-1 comparator; Retatrutide adds glucagon receptor agonism as a third mechanistic axis studied in published preclinical models.

Structurally, Retatrutide is a 39-residue peptide made by solid-phase synthesis and incorporates three non-coded amino acid modifications: 2-aminoisobutyric acid (Aib) at positions 2 and 20 for DPP-4 resistance, plus α-methyl-leucine (αMeL) at position 13 to optimize GIP receptor activity. A C20 fatty diacid moiety is attached to the lysine residue at position 17 through an AEEA-γGlu linker, supporting albumin binding and an extended pharmacokinetic half-life in research models. That lipid modification also contributes to the late HPLC retention time shown above (∼17.8 min), reflecting greater hydrophobicity than smaller research peptides.

Research Background & Published Literature

Retatrutide is a prominent incretin-family research peptide in recent published pharmacology literature. Jastreboff and colleagues reported phase 2 clinical-study findings for the LY3437943 program, while Coskun et al. described receptor binding, signaling profile, and proof-of-concept pharmacology in preclinical systems. These sources are provided for literature context only and do not change the Nexus research-use-only status of this material.

Researchers reviewing the literature around this compound can use the peer-reviewed resources below for additional context on mechanism of action, signaling pathways, and controlled laboratory research applications:

• Jastreboff et al. (2023) — N Engl J Med
• Rosenstock et al. (2023) — Lancet

Storage, Handling & Stability Guidelines

Store lyophilized Retatrutide at -20°C for long-term stability. Because this compound is a larger 39-amino-acid peptide with a long fatty acid modification, reconstituted aliquots should be used within 14 days when stored at 2–8°C, and freeze-thaw exposure should be reduced through aliquoting according to laboratory standard operating procedures.

• Keep ambient-temperature handling time as short as practical to support compound integrity.
• Reseal vials promptly after each withdrawal to limit moisture exposure.
• Use appropriate personal protective equipment and follow institutional chemical safety protocols at all times.
• For traceability, label all aliquots with compound name, concentration, reconstitution date, and operator initials.

Lab Verification

Nexus maintains batch-level verification records for research compounds in the Lab Verified archive, including HPLC purity review and Mass Spectrometry identity confirmation where current lot data is available.