RESUMO
The melanocortin-4 receptor (MC4R) is a centrally expressed, class A GPCR that plays a key role in the regulation of appetite and food intake. Deficiencies in MC4R signaling result in hyperphagia and increased body mass in humans. Antagonism of MC4R signaling has the potential to mitigate decreased appetite and body weight loss in the setting of anorexia or cachexia due to underlying disease. Herein, we report on the identification of a series of orally bioavailable, small-molecule MC4R antagonists using a focused hit identification effort and the optimization of these antagonists to provide clinical candidate 23. Introduction of a spirocyclic conformational constraint allowed for simultaneous optimization of MC4R potency and ADME attributes while avoiding the production of hERG active metabolites observed in early series leads. Compound 23 is a potent and selective MC4R antagonist with robust efficacy in an aged rat model of cachexia and has progressed into clinical trials.
Assuntos
Apetite , Receptor Tipo 4 de Melanocortina , Ratos , Humanos , Animais , Caquexia/tratamento farmacológico , Anorexia/tratamento farmacológico , Conformação MolecularRESUMO
COVID-19 caused by the SARS-CoV-2 virus has become a global pandemic. 3CL protease is a virally encoded protein that is essential across a broad spectrum of coronaviruses with no close human analogs. PF-00835231, a 3CL protease inhibitor, has exhibited potent in vitro antiviral activity against SARS-CoV-2 as a single agent. Here we report, the design and characterization of a phosphate prodrug PF-07304814 to enable the delivery and projected sustained systemic exposure in human of PF-00835231 to inhibit coronavirus family 3CL protease activity with selectivity over human host protease targets. Furthermore, we show that PF-00835231 has additive/synergistic activity in combination with remdesivir. We present the ADME, safety, in vitro, and in vivo antiviral activity data that supports the clinical evaluation of PF-07304814 as a potential COVID-19 treatment.
Assuntos
Tratamento Farmacológico da COVID-19 , Proteases 3C de Coronavírus/antagonistas & inibidores , Inibidores de Protease de Coronavírus/administração & dosagem , Indóis/administração & dosagem , Leucina/administração & dosagem , Pirrolidinonas/administração & dosagem , Monofosfato de Adenosina/administração & dosagem , Monofosfato de Adenosina/efeitos adversos , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacocinética , Alanina/administração & dosagem , Alanina/efeitos adversos , Alanina/análogos & derivados , Alanina/farmacocinética , Animais , COVID-19/virologia , Chlorocebus aethiops , Coronavirus Humano 229E/efeitos dos fármacos , Coronavirus Humano 229E/enzimologia , Inibidores de Protease de Coronavírus/efeitos adversos , Inibidores de Protease de Coronavírus/farmacocinética , Modelos Animais de Doenças , Desenho de Fármacos , Sinergismo Farmacológico , Quimioterapia Combinada , Células HeLa , Humanos , Indóis/efeitos adversos , Indóis/farmacocinética , Infusões Intravenosas , Leucina/efeitos adversos , Leucina/farmacocinética , Camundongos , Pirrolidinonas/efeitos adversos , Pirrolidinonas/farmacocinética , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/efeitos dos fármacos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/enzimologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia , Células VeroRESUMO
In recent years, the first generation of ß-secretase (BACE1) inhibitors advanced into clinical development for the treatment of Alzheimer's disease (AD). However, the alignment of drug-like properties and selectivity remains a major challenge. Herein, we describe the discovery of a novel class of potent, low clearance, CNS penetrant BACE1 inhibitors represented by thioamidine 5. Further profiling suggested that a high fraction of the metabolism (>95%) was due to CYP2D6, increasing the potential risk for victim-based drug-drug interactions (DDI) and variable exposure in the clinic due to the polymorphic nature of this enzyme. To guide future design, we solved crystal structures of CYP2D6 complexes with substrate 5 and its corresponding metabolic product pyrazole 6, which provided insight into the binding mode and movements between substrate/inhibitor complexes. Guided by the BACE1 and CYP2D6 crystal structures, we designed and synthesized analogues with reduced risk for DDI, central efficacy, and improved hERG therapeutic margins.