GPR40 agonist
BI-2081
BI-2081 is a partial agonist GPR40 with a good in vitro potency, reducing the plasma glucose concentration in Zucker diabetic fatty (ZDF) rats. It possesses a good in vitro and in vivo PK profile, which makes an oral application with high bioavailability possible. The structurally related BI-0340 is a suitable negative control due to its significant lower potency on GPR40.
More information
The GPR40, also known as free fatty acid receptor 1 (FFA1), is a member of the rhodopsin family of G-protein coupled receptors and it interacts predominantly with the Gαq subunit1. The receptor is related to other fatty acid receptors (i.e. GPR43/FFA2 and GPR41FFA3) and shares an overall sequence homology of up to 50% with this family2. GPR40 is highly expressed in the β-cells of the pancreas. Additionally, it can be found in the brain and the GI tract3. The receptor is activated by medium to long chain saturated and unsaturated fatty acids (C12-C20). Activation of GPR40 leads to an increase of intracellular Ca2+ concentrations via the IP3 pathway and stimulates the insulin release in the presence of glucose. The GPR40 agonist should have a low risk of hypoglycemia due to this glucose-stimulated insulin secretion (GSIS)4.
Structure of GPR40 with an agonist related to BI-2081, as revealed by X-ray crystallography (PDB code: 4HPU)
BI-2081 is a partial agonist on GPR40 and shows a high cellular potency in the human IPOne assay (EC50 = 3-5 nM). The plasma shift with 4.5% HSA on the human GPR40 is fourfold with BI-2081. The cellular potency of BI-0340 (EC50 = 1230 nM) on the human GPR40 receptor is more than 200-fold lower compared to the probe BI-2081.
| Probe name / negative control | BI-2081 | BI-0340 |
| MW [Da]a | 534.6 | 568.7 |
| Ki [nM] hGPR40 | 23 | - |
| IPOne (EC50) human [nM]b/c | 5/3 | 1230/- |
| IPOne (EC50) rat [nM]b/c | 302/20 | 3630/- |
| IPOne (EC50) mouse [nM]c | 31 | - |
| IPOne (EC50) dog [nM]c | 6 | - |
| IPOne (EC50) cyno [nM]b | 76 | - |
aFor the salt form you will get, please refer to the label on the vial and for the molecular weight of the salt, please refer to the FAQs
bStimulation of 1321N1 cells, which express the GPR40 receptor, followed by measurement of the IP1 accumulation by fluorescence.
cStimulation of 1321N1 cells, which express the GPR40 receptor, followed by measurement of the IP1 accumulation by fluorescence. Differs mainly from assay a by different cell preparation and LiCl containing stimulation buffer. More detailed information can always be obtained via the “Contact us” formular.
BI-2081 has a good permeability and a high plasma protein binding. It displays a high stability in microsomes in human and rat cells, but seems to have a lower stability in hepatocytes. However, this in vitro result does not correlate to the low clearance in vivo which was observed in rats.
| Probe name / negative control | BI-2081 | BI-0340 |
| logD @ pH 7.4 | 3.9 | 2.6 |
| Solubility @ pH 6.8 [µg/mL] | 28 | 100 |
| Caco-2 permeability AB @ pH 7.4 [*10-6 cm/s] | 65.2 | 4.1 |
| Caco-2 efflux ratio | 1.2 | 1.6 |
| Microsomal stability (human/rat/dog) [% QH] | <23/<2 / <202 | 61/>88 / n.a. |
| Hepatocyte stability (human/rat/dog) [% QH] | 90 / 67 / 94 | n.a. |
| Plasma Protein Binding (human/rat/dog) [%] | >99.7 / >99.8 / >99.7 | n.a. |
| hERG [inh. % @ 10 µM] | 22 | n.a. |
| CYP 3A4 (IC50) [µM] | 40 | n.a. |
| CYP 2C8 (IC50) [µM] | 5.4 | n.a. |
| CYP 2C19 (IC50) [µM] | >50 | n.a. |
| CYP 2D6 (IC50) [µM] | >50 | n.a. |
| MBI 3A4 (25 µM) [%Ctrl] | 92 | n.a. |
BI-2081 possesses high bioavailability and an overall good PK profiles in rats. The observed in vivo clearance is low despite the in vitro measured low stability in hepatocytes.
| BI-2081 | Rat |
|---|---|
| Clearance [% QH]a | 3.1 |
| Mean residence time after i.v. dose [h] | 3.9 |
| Cmax_dn [nM] | 930 |
| tmax (h) | 1.2 |
| F [%] | 79 |
| Vss [L/kg] | 0.7 |
ai.v. dose: 0.5 mg/kg
bp.o. dose: 5 mg/kg
An acute oral glucose test (oGTT) in male Zucker diabetic fatty (ZDF) rats was performed with BI‑2081. We observed a strong glucose lowering effect as well as an increase of the plasma insulin level compared to the untreated ZDF rats. The compound reduced the glucose level in this disease-related model by 71% (AUC0-180 min) with ED50 = 0.7 mg/kg and ED100 around 10 mg/kg. No significant change of the plasma glucose level was observed in GPR40 KO mice compared to the WT, which shows the on-target-related specificity. Another study on normal fasting rats showed that there was no significant difference in glucose levels between BI-2081 treated rats and the control group, supporting the low risk of hypoglycemia due to the glucose-dependent mode of action on GPR40.
We observed a significant lowering of HbA1c (ΔHbA1c = −1.8%) after treating male ZDF rats with BI-2081 in a subchronic 30 day study (10 mg/kg b.i.d.). We could additionally observe in the same study that BI-2081 lowers plasma lipids such as total cholesterol (39%), triglycerides (25%) and free fatty acids (34%). The body weight of the treated rats was reduced by 14% after 30 days without any effect on food consumption.
| in vivo study | Observed Effect |
| oGTT in 8-10 old male ZDF rats |
|
| subchronic study male ZDF rats: 10 mg/kg bid, 30 day |
|
The negative control BI-0340 has a similar structure to BI-2081, but it is more than 200-fold less potent on human GPR40 compared to BI-2081 in the IPOne assay.
BI-0340 which serves as a negative control
The selectivity profile for BI-2081 was assessed with the Eurofins Safety Panel 44™ assay. BI-2081 had an affinity towards adrenergic α2A (Ki = 1.3 µM), histamine H1 (Ki = 3.1 µM), CysLT1 (69% inh. @ 10 µM) and thyroid hormone (rat, Ki = 3.5 µM).
Negatiave control BI-0340 hits 1 from 44 in SafetyScreen44TM (GCORTICOID/H>50% at 10µM).
| SELECTIVITY DATA AVILABLE | BI-2081 | BI-0340 |
SafetyScreen44™ with kind support of  | Yes | Yes |
| Invitrogen® | No | No |
| DiscoverX® | No | No |
| Dundee | No | No |
Download selectivity data:
BI-2081_selectivityData.xlsx
BI-0340_selectivityData.xlsx
Fasiglifam hemihydrate (TAK875)
BI-2081 is a partial GPR40 agonist with a high in vitro potency (EC50 = 4 nM) and a good in vitro and in vivo PK profile.
When you plan a publication, please use the following acknowledgement:
BI-2081 was kindly provided by Boehringer Ingelheim via its open innovation platform opnMe, available at https://www.opnme.com.