Consider Eurofins DiscoverX’s custom development capabilities for custom cell lines, assays, & enzyme development.
Obesity and Diabetes Product Solutions
Accelerate the Development of Peptide Therapeutics for Obesity and Diabetes with MOA-reflective Assays
Obesity and Type 2 diabetes (T2D) are chronic diseases that affect a significant number of people globally. The increased incidence of obesity and T2D presents a substantial public health challenge. Only recently have therapeutics proven effective in treating obesity been developed and approved. Many emerging peptide therapeutics focus on hormones of the incretin family, like GLP-1 (glucagon-like peptide-1) and GIP (gastric inhibitory polypeptide), with modifications to prolong their effects and improve efficacy. FDA (US Food and Drug Administration) approved drugs like Semaglutide (Ozempic® and Wegovy®), a long-acting GLP-1 agonist, and Tirzepatide (Mounjaro®), a novel unimolecular GLP-1/GIP receptor dual agonist, show potent glucose-lowering and weight-reducing effects.
The market continues to advance with recent developments, including the GLP-1-GIP-GCG triple-agonist peptide Retatrutide (LY3437943, Eli Lilly), that acts on the glucagon receptor (GCGR) alongside GLP-1R and GIPR, demonstrating synergistic weight-reducing properties while addressing hyperglycemia. These advancements have spurred a global surge in clinical development programs, focusing on innovator drugs, biosimilars, and small molecules targeting these receptors.
Eurofins DiscoverX® supports this evolving therapeutic landscape with a comprehensive portfolio of assays tailored for various peptide therapeutics directed at these three targets (GLP-1, GIP, GCG) and others. These assays support various drug discovery and clinical development stages, as well as commercialization and stability studies facilitating precise bio-identity and potency testing. Widely utilized in global drug development programs and cited in publications, Eurofins DiscoverX assays align with industry standards and regulatory requirements, supporting robust characterization and regulatory submissions.
Product Highlights
- Qualified Bioassays – ICH (International Council for Harmonization) based assay qualification using approved therapeutics like Ozempic® (Semaglutide), Victoza® (Liraglutide), Tirzepatide, and molecules like Retatrutide (under clinical trial)
- Establish Accurate Pharmacology for Regulatory Filings – Evaluate your therapeutics MOA (mechanism of action) for cAMP accumulation, β-arrestin recruitment, and receptor internalization
- Assay Transfer Support to CDMOs – Dedicated global team for end-to-end assay transfer of your commercial release and stability programs at CRO/CDMO sites
- Cell Banking – Customized, well-characterized thaw-and-use working cell banks to ensure long-term assay reproducibility and supply of the bioassay cells
Products
cAMP Potency Assays
Arrestin & Internalization Assays
Assay Principles
Workflow
Resources
Related Pages
Products
New! cAMP Hunter™ Tirzepatide (GLP-1 & GIP RA) Bioassay Kits & cAMP Hunter™ (GLP-1, GIP RA, & GCG) Bioassay Kits
Assays for GLP-1, GIP, and Glucagon
cAMP Accumulation Assays
Quantifying cAMP accumulation is considered the key MOA for most peptide and small molecule therapeutics for GLP-1, GIP, and GCG receptor agonists (RA). Eurofins DiscoverX provides cAMP assays to determine accurate pharmacology and reproducible performance across a wide dynamic range, as shown by our assay qualification data in the cAMP Potency Assays tab.
cAMP Hunter™ GLP-1, GIP, and Glucagon (GCG) Receptor cAMP Accumulation Products
| Targets | Innovator Qualified Bioassay Kits | Target-based Bioassay Kits | Stable Cell Lines (continuous culture) |
eXpress™ Assay Kits |
|---|---|---|---|---|
| GLP-1R |
|
cAMP Hunter GLP-1 RA Bioassay Kit | cAMP Hunter CHO-K1 GLP1R Gs Cell Line | cAMP Hunter eXpress GLP1R CHO-K1 Assays |
| GIPR |
|
cAMP Hunter GIP RA Bioassay Kit | cAMP Hunter CHO-K1 GIPR Gs Cell Line | cAMP Hunter eXpress GIPR CHO-K1 Assay |
| GCGR | Coming Soon cAMP Hunter Retatrutide (GCG RA) Bioassay Kit (Inquire) | cAMP Hunter GCGR Bioassay Kit | cAMP Hunter CHO-K1 GCGR Gs Cell Line | cAMP Hunter eXpress GCGR CHO-K1 Assay |
Bioassays – Ready-to-use, cell-based assay kits with a simple, homogeneous protocol and provided as qualified or target-based assays. These bioassay kits deliver results in less than a day, enabling implementation in QC lot-release programs and transfer across multiple testing sites globally.
- Innovator Qualified Bioassays — Assays optimized with their respective originator drug or reference standard, de-risking their implementation for GMP Lot Release testing. These bioassays can easily reduce assay development timelines by over 12 months. Ideal for biosimilar and biobetter programs. The kits can be customized based on the assay method requirements.
- Target-based Bioassays — Assays optimized with a reference ligand. These assays can be implemented in potency and neutralizing antibody (NAb) testing programs for biologic drug candidates that use the same MOA or specific target and can be further optimized and qualified with the clinical drug candidate.
Thaw-&-use Cell Banks – High quality customized cell banks for various applications, including screening, characterization, and potency testing programs.
β-arrestin Recruitment Assays
Assays evaluating β-arrestin recruitment in addition to second messenger assays (e.g. cAMP) are widely used for characterizing relative intrinsic receptor activity and ligand bias to help determine the functional selectivity of therapeutic compounds. Quantifying β-arrestin activity to the activated GPCR is a stoichiometric, sustained, and non-amplified readout offering a closer reflection of the in vivo response to receptor activation.
For example, in experiments with primary islet cells, β-arrestin signaling is shown to limit the insulin response to GLP-1, but not GIP or tirzepatide. Since tirzepatide is imbalanced towards GIP (less potent at GLP-1 receptor), it enhances insulin secretion. Pharmacologically, signaling studies demonstrate that tirzepatide mimics the actions of native GIP at the GIP receptor, but shows an acute bias at the GLP-1 receptor to favor second messenger signaling (cAMP generation) over β-arrestin recruitment. Coincidently, this bias results in weaker GLP-1 receptor internalization as compared with GLP-1. Taken together, the imbalance towards the GIP receptor, combined with signaling bias towards cAMP at the GLP-1 receptor, account for tirzepatide’s clinical success in the treatment of T2D and obesity.
Assessing both cAMP and β-arrestin signaling can facilitate the identification of ligands with specific functional selectivity profiles that can have implications for drug efficacy and safety.
PathHunter® GLP-1, GIP, and Glucagon (GCG) Receptor β-arrestin Recruitment Products
| Targets | Target-based Bioassay Kits | Stable Cell Lines (continuous culture) | eXpress™ Assay Kits |
|---|---|---|---|
| GLP-1R | PathHunter GLP1 (7-37) Bioassay Kit | PathHunter CHO-K1 GLP1R β-Arrestin Cell Line | PathHunter eXpress GLP1R CHO-K1 β-Arrestin Assay |
| GIPR | PathHunter GIPR Bioassay Kit (Inquire) | PathHunter CHO-K1 GIPR β-Arrestin Cell Line | PathHunter eXpress GIPR CHO-K1 β-Arrestin Assay |
| GCGR | PathHunter GCGR Bioassay Kit (Inquire) | PathHunter CHO-K1 GCGR β-Arrestin Cell Line | PathHunter eXpress GCGR CHO-K1 β-Arrestin Assay |
Receptor Internalization Assays
Quantitative internalization assays provide MOA-reflective readouts for detecting ligand bias and differentiating between strongly and weakly internalizing agonist ligands or therapeutics.
PathHunter GLP-1, GIP, and Glucagon (GCG) Receptor Internalization Products
| Targets | Stable Cell Lines (continuous culture) | eXpress™ Assay Kits |
|---|---|---|
| GLP-1R | PathHunter GLP1R Total GPCR Internalization U2OS Cell Line PathHunter GLP1R Activated GPCR Internalization U2OS Cell Line |
PathHunter eXpress GLP1R Total Internalization Assay PathHunter eXpress GLP1R Activated Internalization Assay |
| GIPR | PathHunter GIPR Internalization Cell Line (Inquire) | |
| GCGR | PathHunter GCGR Total GPCR Internalization HEK 293 Cell Line | PathHunter eXpress GCGR Total Internalization Assay |
Assays for Screening, Profiling, Potency, and Lot Release Programs
Confidently expedite regulatory approval of your drug candidates while ensuring consistency and comparability in their evaluation across different regulatory jurisdictions, facilitating global drug development efforts.
Three Key GPCR Readouts
Publications
Publications Citing DiscoverX Assays for Characterizing Therapeutics Targeting Obesity and T2D
DiscoverX assays are extensively employed in global drug development programs for innovator, biosimilar, and biobetter drugs. Researchers and drug developers consistently cite these assays in numerous publications for comprehensive characterization and demonstrating signaling bias of peptide therapeutics.
Novel GLP-1 Receptor Analogs Studies
- Characterization of Ecnoglutide- a novel, cAMP-biased GLP-1 peptide using Eurofins DiscoverX’s cAMP, β-arrestin-2 recruitment, and receptor internalization assays. Guo W, et al., Mol Metab. 2023 Sep;75:101762. doi:10.1016/j.molmet.2023.101762. Epub 2023 Jun 24. PMID: 37364710; PMCID: PMC10339203.
- Characterizing GL0034- A Novel, Long-acting GLP-1 Receptor Agonist using Eurofins DiscoverX’s β-arrestin-2 recruitment assay. Jones B, et al., Diabetes Obes Metab. 2022 Nov;24(11):2090-2101. doi: 10.1111/dom.14794. Epub 2022 Jul 18. PMID: 35676825; PMCID: PMC9796023.
- Characterization Of Danuglipron, a Novel Small-Molecule, GLP-1R agonist using Eurofins DiscoverX’s β-arrestin-1 and β-arrestin-2 recruitment assay. David A. Griffith et al., J Med Chem. 2022 Jun 23;65(12):8208-8226. doi: 10.1021/acs.jmedchem.1c01856. Epub 2022 Jun 1. PMID: 35647711; PMCID: PMC9234956.
- Characterization of LY3502970, a Potent and Selective Small-molecule GLP-1R Agonist using Eurofins DiscoverX’s β‐arrestin‐2 recruitment assay. Takahiro Kawai et al., PNAS 2020 Nov 11; 117(47):29959-29967. doi:10.1073/pnas.2014879117.
- Assessment of Ligand Bias of a GLP-1R Agonist using Eurofins DiscoverX’s β-arrestin-1 and β-arrestin-2 recruitment assay. Zhang, H., Sturchler, E., Zhu, J. et al. Nat Commun 6, 8918 (2015). https://doi.org/10.1038/ncomms9918
Novel GLP-1, GIP, or GCG Receptor Co-agonists Studies
- Signaling Bias of Tirzepatide- a novel, GLP-1/GIP dual agonist peptide using Eurofins DiscoverX’s β-arrestin-2 recruitment assays. Willard FS et al., JCI Insight. 2020 Sep 3;5(17):e140532. PMID: 32730231; PMCID: PMC7526454.
- A Novel Triple Glucagon, GIP, and GLP-1 Receptor Agonist using Eurofins DiscoverX’s β-arrestin-2 recruitment assays. Coskun T, et al., Cell Metab. 2022 Sep 6;34(9):1234-1247.e9. doi: 10.1016/j.cmet.2022.07.013. Epub 2022 Aug 18. PMID: 35985340.
Frequently Asked Questions
- Which is the preferred assay for testing GPCR-based obesity or diabetes therapeutics in potency and lot-release applications?
Regulatory guidelines, such as those from the FDA (US Food and Drug Administration) and EMEA (European Medicines Evaluation Agency), emphasize the importance of potency assays that adequately measure the relevant mechanism of action (MOA) of drug therapeutics. For various peptide therapeutics directed at the three key GPCR targets (GLP-1, GIP, and glucagon (GCG) receptors), this typically involves demonstrating the ability to stimulate cAMP production in a manner consistent with their intended pharmacological effects on insulin secretion and glucose metabolism.
Measuring cAMP production is a classical method to assess GPCR receptor activity since it reflects the activation of the Gαs-mediated signaling pathway downstream of the receptor and provides a direct and quantitative readout of receptor-mediated signaling. This measurement can be used to compare the potency of different agonists such as semaglutide, tirzepatide, liraglutide, etc.
Eurofins DiscoverX offers MOA-reflective, thaw-and-use cAMP Hunter bioassays that are phase-appropriate for potency testing for GLP-1R and GIPR activation and are rigorously qualified with innovator drugs such as semaglutide, tirzepatide, and retatrutide to establish fit-for-purpose assays for potency and stability testing studies. - How do β-arrestin recruitment and receptor internalization assays contribute to establishing pharmacological profiles for biased agonists targeting the GLP-1, GIP, and glucagon receptors?
The use of dual and triple agonists to initiate synergistic effects in treating obesity and other metabolic diseases is an emerging area of interest. To establish accurate pharmacology for these therapeutics, the three key GPCR readouts – cAMP, β-arrestin, and receptor internalization – are evaluated.
Quantifying β-arrestin activity (recruitment) in response to GPCR activation is a stoichiometric, sustained, and non-amplified readout that closely reflects the in vivo response to receptor activation, while internalization assays track receptor activation and recycling. This dual analysis is instrumental in optimizing multi-agonist therapies, such as achieving the right balance between GLP-1R and GIPR activity to maximize therapeutic effects and minimize side effects.
An example is tirzepatide, recently approved by the FDA that acts as a biased dual agonist, favoring GIPR over GLP-1R activity. The therapeutic exhibits a pronounced cAMP signaling bias over β-arrestin recruitment at the GLP-1R, thereby reducing GLP-1R internalization. - How does overexpression of the GLP-1 receptor impact the potency of the cAMP readout?
Overexpression of the GLP-1 receptor can impact the potency of the cAMP readout. When GLP-1 receptors are overexpressed, the increased receptor density can enhance the sensitivity of the cAMP signaling pathway. This often results in a lower EC50 value, indicating a higher apparent potency of agonists. However, this effect may not accurately reflect the in vivo pharmacological activity, as it is an amplified read-out.
To address this, using a doxycycline-inducible GLP-1R cell line, stimulation with defined concentrations of doxycycline results in reproducible differences in receptor expression – correlating with low, medium, and high receptor densities – providing a more accurate estimation of cAMP EC50. This approach allows for the assessment of agonist potency across different receptor densities, offering a clearer understanding of how receptor expression levels influence signaling. By utilizing these inducible cell lines, researchers can better interpret potency data and ensure that it is relevant and translatable to physiological conditions.
View more Frequently Asked Questions for about Eurofins DiscoverX’s bioassays vs cell lines, Cell Banking Program (including long term support for bioassays), custom method development and qualification services, assay transfer support to CRO/CDMO sites, and more.