Semaglutide Sodium

Semaglutide is selected as the optimal once weekly candidate. Semaglutide has two amino acid substitutions compared to human GLP-1 (Aib8, Arg34) and is derivatized at lysine 26. The GLP-1R affinity of semaglutide (0.38 ± 0.06 nM) is three-fold decreased compared to liraglutide, whereas the albumin affinity is increased.^[2]

Frozen aliquots of BHK cells that express both the hGLP-1R and CRE firefly luciferase (clone FCW467-12A/KZ10-1) are thawed, washed twice in PBS, and suspended in assay buffer. Cells are plated out into 96-well plates at 5000 cells/well in a volume of 50 μL. Compounds to be tested are diluted in assay buffer and a 50 μL aliquot transferred to the plate containing the cells to reach final assay concentrations of 1 × 10⁻¹⁴ − 1 × 10⁻⁷ M. The plate is incubated for 3 h at 5% CO₂ at 37 °C. The plate was allowed to stand at room temperature for 15 min prior to adding 100 μL of steadylite plus reagent. The plate is covered to protect it from light and shaken at room temperature for 30 min. The plate is read in a TopCount NXT instrument.

The plasma half-life is 46.1 h in mini-pigs following i.v. administration, and semaglutide has an MRT of 63.6 h after s.c. dosing to mini-pigs.^[2]