Pharmacokinetics, Metabolism, and Partial Biodistribution of “Pincer Therapeutic” Nitazoxanide in Mice following Pulmonary Delivery of Inhalable Particles

Nitazoxanide (NTZ) induces autophagy in mammalian cells and also has mycobactericidal activity, displaying a two-pronged therapeutic effect, on the host as well as the pathogen. The pharmacokinetics and biodistribution of inhaled NTZ were investigated. Particles containing NTZ in a matrix of PLGA were prepared by spray drying. HPLC and LC–MS/MS methods were developed and validated. Particles were administered as inhalations to mice. Drug concentrations in plasma and tissues were estimated at different time points. Drug loading (∼36%), entrapment efficiency (>90%), and the conversion of NTZ into metabolites in plasma and lung homogenates were assessed satisfactorily by HPLC. NTZ pharmacokinetics and biodistribution following intravenous administration or inhalation were established by LC–MS. NTZ converted into tizoxanide (99% in 30 min) and other metabolites. Pulmonary delivery of NTZ entrapped in particles increased the half-life of the drug by factors of 3, 12, and 200 in the plasma, lung tissue, and alveolar macrophages, respectively. Targeted delivery and prolonged lung retention along with dose sparing of the kidneys was observed upon pulmonary delivery as compared to intravenous administration

Crystallization-Induced Dynamic Resolution toward the Synthesis of (<i>S</i>)‑7-Amino‑5<i>H</i>,7<i>H</i>‑dibenzo[<i>b</i>,<i>d</i>]‑azepin-6-one: An Important Scaffold for γ‑Secretase Inhibitors

An enantioselective synthesis of (<i>S</i>)-7-amino-5<i>H</i>,7<i>H</i>-dibenzo­[<i>b</i>,<i>d</i>]­azepin-6-one (<i>S</i>-<b>1</b>) is described. The key step in the sequence involved crystallization-induced dynamic resolution (CIDR) of compound <b>7</b> using Boc-d-phenylalanine as a chiral resolving agent and 3,5-dichlorosalicylaldehyde as a racemization catalyst to afford <i>S</i>-<b>1</b> in 81% overall yield with 98.5% enantiomeric excess

Nanocarrier Composed of Magnetite Core Coated with Three Polymeric Shells Mediates LCS‑1 Delivery for Synthetic Lethal Therapy of BLM-Defective Colorectal Cancer Cells

Synthetic lethality is a molecular-targeted therapy for selective killing of cancer cells. We exploited a lethal interaction between superoxide dismutase 1 inhibition and Bloom syndrome gene product (BLM) defect for the treatment of colorectal cancer (CRC) cells (HCT 116) with a customized lung cancer screen-1-loaded nanocarrier (LCS-1-NC). The drug LCS-1 has poor aqueous solubility. To overcome its limitations, a customized NC, composed of a magnetite core coated with three polymeric shells, namely, aminocellulose (AC), branched poly­(amidoamine), and paraben-PEG, was developed for encapsulating LCS-1. Encapsulation efficiency and drug loading were found to be 74% and 8.2%, respectively. LCS-1-NC exhibited sustained release, with ∼85% of drug release in 24 h. Blank NC (0.5 mg/mL) exhibited cytocompatibility toward normal cells, mainly due to the AC layer. LCS-1-NC demonstrated high killing selectivity (104 times) toward BLM-deficient HCT 116 cells over BLM-proficient HCT 116 cells. Due to enhanced efficacy of the drug using NC, the sensitivity difference for BLM-deficient cells increased to 1.7 times in comparison to that with free LCS-1. LCS-1-NC induced persistent DNA damage and apoptosis, which demonstrates that LCS-1-NC effectively and preferentially killed BLM-deficient CRC cells. This is the first report on the development of a potential drug carrier to improve the therapeutic efficacy of LCS-1 for specific killing of CRC cells having BLM defects

Evolution of a Scale-Up Synthesis to a Potent GluN2B Inhibitor and Its Prodrug

This paper describes the efficient scale-up synthesis of the potent negative allosteric glutamate N2B (GluN2B) inhibitor <b>1</b> (BMS-986169), which relies upon a stereospecific S_N2 alkylation strategy and a robust process for the preparation of its phosphate prodrug <b>28</b> (BMS-986163) from parent <b>1</b> using POCl₃. A deoxyfluorination reaction employing bis­(2-methoxyethyl)­aminosulfur trifluoride (Deoxo-Fluor) is also used to stereospecifically introduce a fluorine substituent. The optimized routes have been demonstrated to provide APIs suitable for toxicological studies in vivo

The Discovery of GSK3640254, a Next-Generation Inhibitor of HIV‑1 Maturation

GSK3640254 is an HIV-1 maturation inhibitor (MI) that exhibits significantly improved antiviral activity toward a range of clinically relevant polymorphic variants with reduced sensitivity toward the second-generation MI GSK3532795 (BMS-955176). The key structural difference between GSK3640254 and its predecessor is the replacement of the para-substituted benzoic acid moiety attached at the C-3 position of the triterpenoid core with a cyclohex-3-ene-1-carboxylic acid substituted with a CH2F moiety at the carbon atom α- to the pharmacophoric carboxylic acid. This structural element provided a new vector with which to explore structure–activity relationships (SARs) and led to compounds with improved polymorphic coverage while preserving pharmacokinetic (PK) properties. The approach to the design of GSK3640254, the development of a synthetic route and its preclinical profile are discussed. GSK3640254 is currently in phase IIb clinical trials after demonstrating a dose-related reduction in HIV-1 viral load over 7–10 days of dosing to HIV-1-infected subjects

The Discovery of GSK3640254, a Next-Generation Inhibitor of HIV‑1 Maturation

GSK3640254 is an HIV-1 maturation inhibitor (MI) that exhibits significantly improved antiviral activity toward a range of clinically relevant polymorphic variants with reduced sensitivity toward the second-generation MI GSK3532795 (BMS-955176). The key structural difference between GSK3640254 and its predecessor is the replacement of the para-substituted benzoic acid moiety attached at the C-3 position of the triterpenoid core with a cyclohex-3-ene-1-carboxylic acid substituted with a CH2F moiety at the carbon atom α- to the pharmacophoric carboxylic acid. This structural element provided a new vector with which to explore structure–activity relationships (SARs) and led to compounds with improved polymorphic coverage while preserving pharmacokinetic (PK) properties. The approach to the design of GSK3640254, the development of a synthetic route and its preclinical profile are discussed. GSK3640254 is currently in phase IIb clinical trials after demonstrating a dose-related reduction in HIV-1 viral load over 7–10 days of dosing to HIV-1-infected subjects

Discovery of a Highly Selective JAK2 Inhibitor, BMS-911543, for the Treatment of Myeloproliferative Neoplasms

JAK2 kinase inhibitors are a promising new class of agents for the treatment of myeloproliferative neoplasms and have potential for the treatment of other diseases possessing a deregulated JAK2-STAT pathway. X-ray structure and ADME guided refinement of C-4 heterocycles to address metabolic liability present in dialkylthiazole <b>1</b> led to the discovery of a clinical candidate, BMS-911543 (<b>11</b>), with excellent kinome selectivity, <i>in vivo</i> PD activity, and safety profile