METHOD DEVELOPMENT AND VALIDATION OF ERYTHROMYCIN AND OLAPARIB IN HUMAN PLASMA BY LIQUID CHROMATOGRAPHY–TANDEM MASS SPECTROMETRY

The liquid chromatography–tandem mass spectrometry (LC-MS)/MS methodology was used to develop and validate a method for detecting erythromycin and olaparib in human plasma. Antibiotics such as erythromycin and olaparib fall into this category. Liquid chromatography is used to separate stationary and mobile phases based on differences in their affinities as well as to remove unwanted contaminants. It improves repeatability, sensitivity, resilience, and low-level protein detection. A C18 (C18, 5 m, 100×4.6 mm) column is utilized for high resolution and peak area. The calibration curve is created using linear regression. Internally, telmisartan is utilized as a benchmark. The flow rate of the mobile phase is 0.5 mL/min. Erythromycin and olaparib have mass-to-charge ratios of 735.43–115.97 and 435.08–102.04, respectively. Erythromycin in combination with olaparib resulted in a 98% recovery rate. The precision and accuracy of the results determined by interday QC samples are within acceptable limits. There was no evidence of instability

Preclinical formulation for the pharmacokinetics and efficacy of GBO-006, a selective polo like kinase 2 (PLK2) inhibitor for the treatment of triple negative breast cancer

GBO-006 was shown to be a highly specific and selective PLK2 inhibitor that promoted mitotic arrest in various cancer cell lines, subsequently resulting in their apoptotic death. Intraperitoneal alternate day dosing of GBO-006 using 100 % DMSO as formulation showed significant tumor regression in xenograft models, demonstrating proof of concept of PLK2 inhibition in vivo. These studies necessitated the development of a suitable and GRAS (generally considered as safe) preformulation for pharmacokinetic and efficacy studies. GBO-006 possesses challenging physicochemical and biopharmaceutical properties like poor solubility in aqueous media, low permeability and a crystalline nature. Different methods like cosolvency, complexation and micellar solubilization were employed to improve the solubility of GBO-006. A strategy of co-solvency is used to solubilize the GBO-006 up to 10 mg/mL. A formulation with 20 % DMSO, 40 % PEG 400, 30 % of 100 mM citrate buffer (pH 3.0) and 10 % solutol displayed clear solution without any visual precipitation of the drug even after 2 weeks of storage. GBO-006 showed moderate clearance in rat and high systemic clearance in mouse and dog. It showed poor oral bioavailability across all species. Intraperitoneal dosing of GBO-006 demonstrated the linear exposure. GBO-006 showed significant inhibition of tumor progression

Role of in vitro two-dimensional (2D) and three-dimensional (3D) cell culture systems for ADME-Tox screening in drug discovery and development: a comprehensive review

Drug discovery and development have become a very time-consuming and expensive process. Preclinical animal models have become the gold standard for studying drug pharmacokinetic and toxicity parameters. However, the involvement of a huge number of animal subjects and inter-species pathophysiological variations between animals and humans has provoked a lot of debate, particularly because of ethical concerns. Although many efforts are being established by biotech and pharmaceutical companies for screening new chemical entities in vitro before preclinical trials, failures during clinical trials are still involved. Currently, a large number of two- dimensional (2D) in vitro assays have been developed and are being developed by researchers for the screening of compounds. Although these assays are helpful in screening a huge library of compounds and have shown perception, there is a significant lack in predicting human Absorption, Distribution, Metabolism, Excretion and Toxicology (ADME-Tox). As a result, these assays cannot completely replace animal models. The recent inventions in three-dimensional (3D) cell culture-based assays like organoids and micro-physiological systems have shown great potential alternative tools for predicting the compound pharmacokinetic and pharmacodynamic fate in humans. In this comprehensive review, we have summarized some of the most commonly used 2D in vitro assays and emphasized the achievements in next-generation 3D cell culture-based systems for predicting the compound ADME-Tox

Evaluation of pharmacokinetic and pharmacodynamic interaction between repaglinide and atazanavir in healthy, diabetic and hepatic impaired rats: possible inhibition of CYP3A, OATP, and P-glycoprotein transporters

The metabolic syndrome in HIV infected patients is particularly associated with the use protease inhibitors. Atazanavir is an inhibitor of the cytochrome P 450 (CYP) system, in particular CYP3A4 and CYP2C9 which can affect the metabolism of several drugs. To treat metabolic syndrome in HIV patients repaglinide is used and it is a short acting insulin secretagogues undergoing metabolism with CYP 3A4 and CYP 2C8 enzyme system. The purpose of this study was to assess the possible pharmacokinetic and pharmacodynamic drug interaction of repaglinide and atazanavir in healthy, diabetic and impaired hepatic function rats. Human oral therapeutic doses of atazanavir and repaglinide were extrapolated to rats based on the body surface area. The pharmacokinetic parameters and blood glucose concentrations of repaglinide were determined after oral administration of repaglinide alone (0.5 mg/kg) and in the presence of atazanavir (36 mg/kg) in normal, diabetic and hepatic impaired rats. The pharmacokinetics (PK) and blood glucose concentrations of repaglinide were significantly altered in the presence of atazanavir. The peak plasma concentration (Cmax), area under the plasma concentration time profile (AUC) and elimination half-life of repaglinide were significantly (P<0.0001) increased. The repaglinide clearance (CL) was significantly (P<0.0001) decreased in the presence of atazanavir treatment. In the presence of atazanavir, repaglinide hypoglycaemic activity was increased significantly (P<0.0001) when compared with the repaglinide control group. The present study demonstrated the significant difference in the PK/PD changes due to the enhanced bioavailability and decreased total body clearance of repaglinide may be due to the inhibition of the CYP P450 metabolic system, OATP and P-gp transporters by atazanavir

Synthesis and characterization of related substances of Azilsartan Kamedoxomil

Azilsartan Kamedoxomil is an AT1-subtype angiotensin II receptor blocker (ARB). During the laboratory synthesis of Azilsartan Kamedoxomil, four related substances of Azilsartan Kamedoxomil were observed and identified. These were 2-Ethoxy-3-[[4-[2- [4-[(5-methyl-2-oxo-1,3-dioxol-4-yl)methyl]-5-oxo-1,2,4-oxadiazol-3-yl]phenyl]phenyl] methyl] benzimidazole-4-carboxylic acid (azilsartan N-medoxomil, 9), (5-methyl-2-oxo- 1,3-dioxol-4-yl)methyl 2-ethoxy-3-[[4-[2-[4-[(5-methyl-2-oxo-1,3-dioxol-4-yl)methyl]-5- oxo-1,2,4-oxadiazol-3-yl]phenyl]phenyl] methyl] benzimidazole-4-carboxylate (azilsartan dimedoxomil, 10), (5-methyl-2-oxo-1,3-dioxo-4-yl)methyl 1-[2’-(4,5-dihydro-5-oxo-4H- 1,2,4-oxadiazol-3-yl)biphenyl-4-yl]methyl]-2-methoxy-1H-benzimidazole-7-carboxylate (methoxy analogue of azilsartan medoxomil, 11), Methyl 1-((2’-amidobiphenyl-4-yl) methyl)-2-ethoxy-1H-benzo[d]imidazole-7-carboxylate (amide methyl ester, 12). The present work describes the origin, synthesis and characterization of these related substances