| Autor: |
Lin K; 2793Merck & Co., Inc, South San Francisco, CA, USA., Cabral P; 2793Merck & Co., Inc, South San Francisco, CA, USA., Ekpenyong O; 2793Merck & Co., Inc, South San Francisco, CA, USA., Bader SE; 2793Merck & Co., Inc, South San Francisco, CA, USA., Galvao J; 2793Merck & Co., Inc, South San Francisco, CA, USA., Kim Y; 2793Merck & Co., Inc, Rahway, NJ, USA., Lu SX; 2793Merck & Co., Inc, South San Francisco, CA, USA., Tam YT; 2793Merck & Co., Inc, South San Francisco, CA, USA., Bruder M; 2793Merck & Co., Inc, South San Francisco, CA, USA., Rearden P; 2793Merck & Co., Inc, South San Francisco, CA, USA., Shankaran H; 2793Merck & Co., Inc, South San Francisco, CA, USA., Beaumont M; 2793Merck & Co., Inc, South San Francisco, CA, USA. |
| Abstrakt: |
A liquid chromatography-tandem mass spectrometry assay was developed and qualified for the multiplexed quantitation of a small molecule stimulator of soluble guanylate cyclase (sGC) and its target engagement biomarker, 3',5'-cyclic guanosine monophosphate (cGMP), in ocular tissues and plasma from a single surrogate matrix calibration curve. A surrogate matrix approach was used in this assay due to the limited quantities of blank ocular matrices in a discovery research setting. After optimization, the assay showed high accuracy, precision, and recovery as well as parallelism between the surrogate matrix and the biological matrices (rabbit plasma, vitreous, and retina-choroid). This assay provided pharmacokinetic and target engagement data after intravitreal administration of the sGC stimulator. The nitric oxide-sGC-cGMP pathway is a potential target to address glaucoma. Increasing sGC-mediated production of cGMP could improve aqueous humor outflow and ocular blood flow. The sGC stimulator showed dose-dependent exposure in rabbit vitreous, retina-choroid, and plasma. The cGMP exhibited a delayed yet sustained increase in vitreous humor but not retina-choroid. Multiplexed measurement of both pharmacokinetic and target engagement analytes reduced animal usage and provided improved context for interpreting PK and PD relationships. |
