Cagrilintide is a 37-residue acylated amylin analogue with activity at amylin receptors and the calcitonin receptor (CTR). Its molecular design combines an amylin-derived peptide scaffold with an N-terminal C20 fatty-diacid modification, a defined Cys2–Cys7 intramolecular disulfide bond, sequence engineering that reduces the aggregation tendency associated with native human amylin, and C-terminal amidation.

Unlike GLP-1 receptor agonists, cagrilintide interacts with members of the calcitonin receptor family. Amylin receptors are formed when the calcitonin receptor associates with receptor activity-modifying proteins RAMP1, RAMP2, or RAMP3, generating AMY₁R, AMY₂R, and AMY₃R, respectively.

This receptor profile makes cagrilintide a useful research peptide for studying amylin-receptor pharmacology, calcitonin-receptor signaling, ligand–GPCR interactions, peptide lipidation, receptor-complex structure, aggregation-resistant peptide design, and structure–activity relationships.

Alan Scientific supplies synthetic cagrilintide for laboratory research with batch-specific analytical documentation, including HPLC and mass spectrometry data as applicable.

Certificates of Analysis (COAs) are batch-specific. Please contact us to request the COA for your product, and we will provide it by email.

Product Information

Cagrilintide Sequence and Molecular Design

Sequence:

{diacid-C20-γ-Glu}KCNTATCATQRLAEFLRHSSNNFGPILPPTNVGSNTP-NH₂

Cagrilintide is derived from an amylin-related peptide scaffold but should not be viewed simply as lipidated native human amylin. Its sequence and terminal chemistry have been deliberately engineered to produce a distinct molecular structure suitable for receptor pharmacology and peptide-design studies.

The peptide contains two cysteine residues that form a defined intramolecular disulfide bond, an N-terminal lysine carrying the fatty-diacid modification, and a C-terminal prolinamide. These structural elements are part of the intended molecular identity and should be considered together when evaluating synthetic material.

The C-terminal region also contains several proline residues. This feature is particularly relevant when comparing cagrilintide with native human amylin, which is well known for its strong tendency to self-associate and form amyloid fibrils.

For experimental use, correct peptide identity therefore involves more than reproducing the linear amino-acid sequence. Lipidation, disulfide formation, terminal chemistry, molecular mass, and chromatographic purity all contribute to the final molecular form.

Cys2–Cys7 Disulfide Bond

Cagrilintide contains a single intramolecular disulfide bond between Cys2 and Cys7, using residue numbering beginning with the N-terminal lysine of the peptide backbone.

This short N-terminal disulfide loop is characteristic of amylin-family peptides and contributes to the conformational organization of the receptor-active molecule.

For synthetic cagrilintide, oxidation state is therefore an identity attribute rather than a secondary formulation detail. Material containing predominantly reduced cysteine residues would not represent the same molecular form as correctly oxidized cagrilintide.

Disulfide formation can also influence chromatographic behavior, folding state, and the interpretation of mass-spectrometric and HPLC data. This makes oxidation control particularly important during synthesis, purification, and final analytical assessment.

N-Terminal C20 Lipidation

The N-terminal lysine of cagrilintide is modified with a C20 fatty diacid through a γ-glutamyl linker.

This acylation substantially changes the physicochemical properties of the peptide relative to the corresponding non-lipidated backbone. The modification increases hydrophobic character and supports reversible association with albumin while also influencing chromatographic retention, solubility, purification behavior, and sample handling.

Recent structural studies indicate that cagrilintide can retain an amylin-like receptor-engaged conformation despite the presence of the lipid modification. From a peptide-design perspective, this makes the molecule useful for examining how a relatively large hydrophobic conjugate can be incorporated into a receptor-active peptide without replacing the underlying peptide–receptor recognition architecture.

The exact attachment site remains important. A peptide with the same amino-acid sequence but an incorrectly positioned lipid group would be a different molecular species and may exhibit different analytical and functional properties.

Researchers developing related acylated amylin analogues, alternative fatty-acid chains, linker architectures, or site-specific lipidation strategies can use Alan Scientific's Custom Peptide Synthesis service for project-specific designs.

Amylin and Calcitonin Receptor Pharmacology

Cagrilintide interacts with the calcitonin receptor family, which has an unusual receptor architecture.

The calcitonin receptor can function independently as CTR or associate with one of three receptor activity-modifying proteins. Association with RAMP1, RAMP2, or RAMP3 produces the corresponding amylin receptor subtypes.

Structural studies have directly visualized cagrilintide bound to active Gs-coupled AMY₁R, AMY₂R, AMY₃R, and CTR complexes.

These structures provide a molecular basis for studying how one peptide ligand can engage multiple related receptor complexes while the associated RAMP proteins alter receptor environment and pharmacological behavior.

Cagrilintide adopts an amylin-like receptor-binding architecture, but its receptor complexes can display conformational dynamics that differ from those produced by other amylin- and calcitonin-family peptides. This makes cagrilintide particularly useful for comparative receptor pharmacology rather than simply categorizing it as an “amylin mimetic.”

Structural Features Relevant to Receptor Interaction

Structural work on cagrilintide has highlighted several sequence regions that are useful for structure–activity studies.

The central portion of the peptide contributes to stabilization of the receptor-engaged conformation, while residues in the C-terminal region participate in interactions with the extracellular portion of the receptor complex.

Phe23 is one residue of particular structural interest because it contributes to stabilization of the peptide within the receptor-bound complex. Intramolecular interactions within the central sequence have also been implicated in maintaining the conformation required for receptor engagement.

These observations create several experimentally useful variables for analog design, including individual residue substitutions, modifications to central helical stability, changes in the C-terminal sequence, altered lipidation chemistry, and modification of disulfide-constrained regions.

For SAR programs, these features are generally more informative when evaluated as parts of an integrated peptide architecture rather than as isolated modifications.

Why the C-Terminal Amide Matters

Cagrilintide terminates with a C-terminal prolinamide.

The amide is part of the defined molecular structure and should not be treated as an interchangeable terminal modification.

Amidation changes the terminal charge state relative to a free C-terminal carboxyl group and can influence peptide conformation and receptor interaction. For amylin-family peptides, the C-terminal region participates in recognition of the receptor extracellular domain, making terminal chemistry particularly relevant to receptor pharmacology.

When evaluating synthetic cagrilintide, the C-terminal amide should therefore be considered alongside the Cys2–Cys7 disulfide bond and N-terminal lipid conjugate.

A high chromatographic purity result does not compensate for an incorrect oxidation state, lipidation pattern, or terminal form.

Cagrilintide as a Lipidated Peptide Research Scaffold

Cagrilintide is useful not only as a receptor ligand but also as a reference structure for the design of chemically modified peptides.

Its molecular architecture combines a biologically active 37-residue backbone with disulfide constraint, terminal amidation, aggregation-related sequence engineering, and a site-specific fatty-diacid conjugate.

These features allow researchers to investigate how several peptide-engineering strategies interact within the same molecule.

For example, changing the lipid chain can alter hydrophobicity and protein association. Changing the linker can alter spacing and local polarity around the conjugation site. Moving the lipid attachment site can affect both synthetic accessibility and peptide conformation. Altering residues involved in aggregation can change physical stability while potentially influencing receptor activity.

This makes cagrilintide relevant to broader research in modified peptide design even when the primary experimental question is not focused exclusively on amylin pharmacology.

Research Applications

Cagrilintide is applicable to research involving amylin-receptor pharmacology, calcitonin-receptor signaling, class B GPCR activation, ligand–receptor interactions, receptor subtype profiling, RAMP-dependent receptor pharmacology, structure–activity relationships, lipidated peptide chemistry, albumin-association studies, peptide aggregation, and analytical characterization of modified peptides.

It can also serve as a reference molecule for comparative studies of native amylin, pramlintide-related sequences, modified amylin analogues, calcitonin-family peptides, and other receptor-active lipidated peptides.

Researchers investigating alternative fatty-acid conjugates, linker designs, disulfide variants, terminal modifications, or sequence substitutions can use cagrilintide as a defined starting architecture for analog development.

Synthetic and Analytical Considerations

Cagrilintide is more complex to synthesize and characterize than a conventional unmodified linear peptide of similar length.

Its final molecular form requires successful assembly of the 37-residue peptide backbone together with correct N-terminal acylation, formation of the Cys2–Cys7 intramolecular disulfide bond, and retention of the intended C-terminal amide.

The lipid modification increases hydrophobicity and can substantially alter purification behavior. At the same time, the amylin-derived sequence requires attention to aggregation and physical stability during synthesis, purification, concentration, and sample preparation.

For this reason, analytical evaluation should not rely solely on a nominal HPLC purity percentage.

A suitable assessment considers molecular identity, lipidation state, oxidation state, terminal chemistry, molecular mass, and chromatographic purity together.

HPLC and Mass Spectrometry

Analytical HPLC provides information about chromatographic composition and the relative abundance of the principal peptide component. For a lipidated peptide, retention behavior may differ markedly from the corresponding non-acylated precursor because the fatty-diacid moiety contributes substantial hydrophobic character.

Mass spectrometry provides complementary information supporting the expected molecular mass of the final modified peptide.

Neither technique alone establishes every structural feature. A species with an incorrect modification state may still appear highly pure chromatographically, while an HPLC trace alone cannot confirm the precise location of a covalent modification.

For cagrilintide, HPLC and MS data are therefore most useful when interpreted together with the known sequence, defined lipidation chemistry, disulfide state, and terminal form.

More information about analytical documentation is available through our Peptide Quality Control resource.

Purity and Experimental Planning

The appropriate purity specification depends on the experimental workflow.

Exploratory analytical studies and method-development experiments may have different requirements from quantitative receptor assays, binding experiments, or sensitive cell-based systems.

For a modified peptide such as cagrilintide, researchers may also need to consider counterion content, residual solvent, peptide content, water content, and endotoxin specification where these parameters are relevant to the planned assay.

The practical objective should be to confirm that the peptide has the correct molecular form and an analytical specification appropriate for the experiment, rather than evaluating material solely by the highest available HPLC percentage.

Our Recommended Peptide Purity guide provides additional application-oriented considerations for selecting peptide specifications.

Cagrilintide Analogs and Custom Peptide Synthesis

Research projects frequently require cagrilintide-related analogues rather than the reference molecule itself.

Alan Scientific can support project-specific sequences incorporating alternative amino-acid substitutions, modified lipid chains, different linker structures, alternative conjugation sites, disulfide variants, terminal modifications, isotopic labels, fluorescent labels, and other research-oriented peptide modifications.

For these molecules, synthesis difficulty is determined by more than peptide length. Hydrophobicity, aggregation tendency, modification chemistry, oxidation requirements, purification behavior, and the analytical specification all influence project design.

Researchers can contact our Custom Peptide Synthesis team for project-specific feasibility assessment and quotation.

Frequently Asked Questions

What is cagrilintide?

Cagrilintide is a 37-residue acylated amylin analogue with activity at amylin receptors and the calcitonin receptor. Its molecular architecture includes an N-terminal C20 fatty-diacid modification, a Cys2–Cys7 disulfide bond, and C-terminal amidation.

How many amino-acid residues are in cagrilintide?

Cagrilintide contains 37 amino-acid residues. The peptide backbone begins with an N-terminal lysine that carries the fatty-diacid modification and terminates with an amidated proline.

What receptors does cagrilintide interact with?

Cagrilintide has activity at AMY₁R, AMY₂R, AMY₃R and CTR. The three amylin receptor subtypes consist of the calcitonin receptor associated with RAMP1, RAMP2, or RAMP3, respectively.

Is cagrilintide a GLP-1 receptor agonist?

Cagrilintide is characterized primarily through amylin receptors and the calcitonin receptor rather than GLP-1R. This makes it useful for research comparing different peptide-receptor systems involved in metabolic signaling.

What is the disulfide bond in cagrilintide?

Cagrilintide contains one intramolecular disulfide bond between Cys2 and Cys7. Correct oxidation of these residues forms part of the intended molecular identity.

Why is cagrilintide lipidated?

The N-terminal fatty-diacid conjugate changes the physicochemical behavior of the peptide and supports reversible albumin association. For laboratory work, lipidation is also important because it affects hydrophobicity, chromatographic retention, purification, solubility, and analytical method development.

Why is the C-terminal amide important?

C-terminal amidation is part of the defined cagrilintide structure. Because the C-terminal region of amylin-family peptides participates in receptor recognition, changing terminal chemistry can produce a molecular species with different physicochemical or pharmacological properties.

Does high HPLC purity confirm cagrilintide identity?

No. HPLC provides important information about chromatographic purity but does not independently confirm the complete molecular structure. For cagrilintide, molecular mass, lipidation state, disulfide formation, terminal chemistry, and chromatographic purity should be considered together.

What makes cagrilintide synthesis technically demanding?

The synthesis combines a moderately long peptide sequence with site-specific fatty-diacid conjugation, disulfide formation, C-terminal amidation, increased hydrophobicity, and the aggregation characteristics associated with amylin-derived peptides. These factors can affect both synthesis and downstream purification.

Can Alan Scientific support custom cagrilintide analogs?

Yes. Alan Scientific's custom peptide synthesis service can support research-oriented cagrilintide analogs with sequence substitutions, alternative lipidation strategies, linker modifications, disulfide variants, and other project-specific modifications. Feasibility and analytical requirements are evaluated according to the individual sequence and requested specification.

Research Use Only

Cagrilintide is supplied for research use only. It is not intended for therapeutic, or human use.