RESUMO
The objective of these studies was to evaluate the exposures of meropenem and vaborbactam that would produce antibacterial activity and prevent resistance development in carbapenem-resistant Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae strains when tested at an inoculum of 108 CFU/ml. Thirteen K. pneumoniae isolates, three Enterobacter cloacae isolates, and one Escherichia coli isolate were examined in an in vitro hollow-fiber model over 32 h. Simulated dosage regimens of 1 to 2 g of meropenem with 1 to 2 g of vaborbactam, with meropenem administered every 8 h by a 3-h infusion based on phase 1 or phase 3 patient pharmacokinetic data, were studied in the model. A dosage of 2 g of meropenem in combination with 2 g of vaborbactam was bactericidal against K. pneumoniae, E. cloacae, and E. coli strains, with meropenem-vaborbactam MICs of up to 8 mg/liter. When the vaborbactam exposure was adjusted to the levels observed in patients enrolled in phase 3 trials (24-h free AUC, â¼550 mg · h/liter, versus 320 mg · h/liter in the phase 1 studies), 2 g of meropenem with 2 g of vaborbactam was also bactericidal against strains with meropenem-vaborbactam MICs of 16 mg/liter. In addition, this level of vaborbactam also suppressed the development of resistance observed using phase 1 exposures. In this pharmacodynamic model, exposures similar to 2 g of meropenem in combination with 2 g of vaborbactam administered every 8 h by a 3-h infusion in phase 3 trials produced antibacterial activity and suppressed the development of resistance against carbapenem-resistant KPC-producing strains of Enterobacteriaceae.
Assuntos
Antibacterianos/farmacologia , Ácidos Borônicos/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Infecções por Enterobacteriaceae/tratamento farmacológico , Meropeném/farmacologia , Proteínas de Bactérias/metabolismo , Infecções por Enterobacteriaceae/metabolismo , Humanos , Testes de Sensibilidade Microbiana/métodosRESUMO
Progressive respiratory failure due to Pseudomonas aeruginosa is the leading cause of morbidity and mortality in patients with cystic fibrosis. The pulmonary delivery of antimicrobial agents provides high concentrations of drug directly to the site of infection and attains pharmacokinetic-pharmacodynamic indices exceeding those which can be achieved with systemic dosing. MP-376 is a new formulation of levofloxacin that enables the safe aerosol delivery of high concentrations of drug to pulmonary tissues. In vivo studies were conducted to demonstrate the efficacy of MP-376 in models of mouse pulmonary infection. The superiority of aerosol dosing over systemic dosing was demonstrated in models of both acute and chronic lung infection. In a model of acute lung infection, aerosol treatment with MP-376 once or twice daily reduced the lung bacterial load to a greater extent than aerosol tobramycin or aztreonam did when they were administered at similar or higher doses. The bacterial killing by aerosol MP-376 observed in the lung in the model of acute pulmonary infection translated to improved survival (P < 0.05). In a model of chronic pulmonary infection, aerosol MP-376 had antimicrobial effects superior to those of aztreonam (P < 0.05) and effects similar to those of tobramycin (P > 0.05). In summary, these data show that aerosol MP-376 has in vivo activity when it is used to treat acute and chronic lung infections caused by P. aeruginosa.
Assuntos
Aerossóis/administração & dosagem , Antibacterianos/uso terapêutico , Levofloxacino , Pneumopatias/tratamento farmacológico , Ofloxacino/uso terapêutico , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/fisiologia , Administração por Inalação , Animais , Antibacterianos/administração & dosagem , Aztreonam/administração & dosagem , Aztreonam/farmacocinética , Aztreonam/uso terapêutico , Modelos Animais de Doenças , Feminino , Pneumopatias/microbiologia , Camundongos , Testes de Sensibilidade Microbiana , Ofloxacino/administração & dosagem , Ofloxacino/farmacocinética , Infecções por Pseudomonas/microbiologia , Tobramicina/administração & dosagem , Tobramicina/farmacocinética , Tobramicina/uso terapêuticoRESUMO
5,6-Dihydro-1H-pyridin-2-one analogs were discovered as a novel class of inhibitors of genotype 1 HCV NS5B polymerase. Among these, compound 4ad displayed potent inhibitory activities in biochemical and replicon assays (IC(50) (1b)<10nM; IC(50) (1a)<25nM, EC(50) (1b)=16nM), good in vitro DMPK properties, as well as moderate oral bioavailability in monkeys (F=24%).
Assuntos
RNA Polimerases Dirigidas por DNA/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Piridonas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Administração Oral , Animais , Disponibilidade Biológica , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Haplorrinos , Piridonas/administração & dosagem , Piridonas/química , Piridonas/farmacocinética , Relação Estrutura-AtividadeRESUMO
The discovery of 5,5'- and 6,6'-dialkyl-5,6-dihydro-1H-pyridin-2-ones as potent inhibitors of the HCV RNA-dependent RNA polymerase (NS5B) is described. Several of these agents also display potent antiviral activity in cell culture experiments (EC50 <0.10 microM). In vitro DMPK data for selected compounds as well as crystal structures of representative inhibitors complexed with the NS5B protein are also disclosed.
Assuntos
Antivirais/química , Inibidores Enzimáticos/química , Hepacivirus/enzimologia , Piridonas/química , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo , Animais , Antivirais/síntese química , Antivirais/farmacologia , Sítios de Ligação , Cristalografia por Raios X , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Humanos , Macaca fascicularis , Microssomos Hepáticos/metabolismo , Piridonas/síntese química , Piridonas/farmacologia , RNA Polimerase Dependente de RNA/metabolismo , Relação Estrutura-AtividadeRESUMO
A novel series of non-nucleoside small molecules containing a tricyclic dihydropyridinone structural motif was identified as potent HCV NS5B polymerase inhibitors. Driven by structure-based design and building on our previous efforts in related series of molecules, we undertook extensive SAR studies, in which we identified a number of metabolically stable and very potent compounds in genotype 1a and 1b replicon assays. This work culminated in the discovery of several inhibitors, which combined potent in vitro antiviral activity against both 1a and 1b genotypes, metabolic stability, good oral bioavailability, and high C(12) (PO)/EC(50) ratios.
Assuntos
Disponibilidade Biológica , Desenho de Fármacos , Relação Estrutura-Atividade , Antivirais/farmacocinética , Química Farmacêutica , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos , Genótipo , Hepacivirus/efeitos dos fármacos , Hepatite C , Estrutura Molecular , RNA Polimerase Dependente de RNA , Proteínas não Estruturais Virais/antagonistas & inibidoresRESUMO
Hexahydro-pyrrolo- and hexahydro-1H-pyrido[1,2-b]pyridazin-2-one analogs were discovered as a novel class of inhibitors of genotype 1 HCV NS5B polymerase. Among these, compound 4c displayed potent inhibitory activities in biochemical and replicon assays (IC(50) (1b) <10 nM; EC(50) (1b)=34 nM) as well as good stability towards human liver microsomes (HLM t(1/2) =59 min).
Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Microssomos Hepáticos/efeitos dos fármacos , Piridazinas/síntese química , Piridazinas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Antivirais/química , Técnicas de Química Combinatória , Cristalografia por Raios X , Desenho de Fármacos , Humanos , Estrutura Molecular , Piridazinas/química , Relação Estrutura-AtividadeRESUMO
5-Hydroxy-3(2H)-pyridazinone derivatives were investigated as potent inhibitors of genotype 1 HCV NS5B polymerase focusing on the optimization of their drug metabolism and pharmacokinetics (DMPK) profiles. This investigation led to the discovery of potent inhibitors with improved DMPK properties.
Assuntos
Antivirais/síntese química , Antivirais/farmacocinética , Hepacivirus/enzimologia , Piridazinas/síntese química , Piridazinas/farmacocinética , Proteínas não Estruturais Virais/antagonistas & inibidores , Administração Oral , Animais , Antivirais/química , Técnicas de Química Combinatória , Desenho de Fármacos , Haplorrinos , Concentração Inibidora 50 , Modelos Moleculares , Estrutura Molecular , Piridazinas/química , Relação Estrutura-AtividadeRESUMO
Pyrrolo[1,2-b]pyridazin-2-one analogs were discovered as a novel class of inhibitors of genotype 1 HCV NS5B polymerase. Structure-based design led to the discovery of compound 3 k, which displayed potent inhibitory activities in biochemical and replicon assays (IC(50) (1b)<10nM; EC(50) (1b)=12 nM) as well as good stability towards human liver microsomes (HLM t(1/2)>60 min).
Assuntos
Antivirais/farmacologia , Piridazinas/farmacologia , Pirróis/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/síntese química , Antivirais/química , Sítios de Ligação/efeitos dos fármacos , Linhagem Celular , Cristalografia por Raios X , Humanos , Ligação de Hidrogênio , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Piridazinas/síntese química , Piridazinas/química , Pirróis/síntese química , Pirróis/química , Relação Estrutura-Atividade , Proteínas não Estruturais Virais/químicaRESUMO
A novel series of HCV NS5B polymerase inhibitors comprising 1,1-dioxoisothiazoles and benzo[b]thiophene-1,1-dioxides were designed, synthesized, and evaluated. SAR studies guided by structure-based design led to the identification of a number of potent NS5B inhibitors with nanomolar IC(50) values. The most potent compound exhibited IC(50) less than 10nM against the genotype 1b HCV polymerase and EC(50) of 70 nM against a genotype 1b replicon in cell culture. The DMPK properties of selected compounds were also evaluated.
Assuntos
Antivirais/síntese química , Antivirais/farmacocinética , Inibidores Enzimáticos/farmacocinética , Tiazóis/síntese química , Tiofenos/síntese química , Proteínas não Estruturais Virais/antagonistas & inibidores , Química Farmacêutica/métodos , Cristalografia por Raios X/métodos , Desenho de Fármacos , Genótipo , Humanos , Concentração Inibidora 50 , Modelos Químicos , Conformação Molecular , RNA Viral/metabolismo , Relação Estrutura-Atividade , Tiazóis/farmacocinética , Tiofenos/farmacocinéticaRESUMO
5-Hydroxy-3(2H)-pyridazinone derivatives were investigated as inhibitors of genotype 1 HCV NS5B polymerase. Lead optimization led to the discovery of compound 3a, which displayed potent inhibitory activities in biochemical and replicon assays [IC(50) (1b)<10nM; IC(50) (1a)=22 nM; EC(50) (1b)=5nM], good stability toward human liver microsomes (HLM t(1/2)>60 min), and high ratios of liver to plasma concentrations 12h after a single oral administration to rats.
Assuntos
Antivirais/síntese química , Antivirais/farmacocinética , Hepacivirus/efeitos dos fármacos , Piridazinas/síntese química , Piridazinas/farmacocinética , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Proteínas não Estruturais Virais/antagonistas & inibidores , Administração Oral , Animais , Antivirais/sangue , Antivirais/química , Técnicas de Química Combinatória , Desenho de Fármacos , Humanos , Microssomos Hepáticos/efeitos dos fármacos , Estrutura Molecular , Piridazinas/sangue , Piridazinas/química , Ratos , Relação Estrutura-AtividadeRESUMO
4-(1,1-Dioxo-1,4-dihydro-1lambda(6)-benzo[1,4]thiazin-3-yl)-5-hydroxy-2H-pyridazin-3-one analogs were discovered as a novel class of inhibitors of HCV NS5B polymerase. Structure-based design led to the identification of compound 3a that displayed potent inhibitory activities in biochemical and replicon assays (1b IC(50)<10 nM; 1b EC(50)=1.1 nM) as well as good stability toward human liver microsomes (HLM t(1/2)>60 min).
Assuntos
Química Farmacêutica/métodos , Hepacivirus/enzimologia , Microssomos Hepáticos/enzimologia , Piridazinas/síntese química , Piridazinas/farmacologia , Tiazinas/síntese química , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/química , Células CACO-2 , Cristalografia por Raios X/métodos , Desenho de Fármacos , Hepacivirus/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Modelos Químicos , Conformação Molecular , Piridazinas/química , Relação Estrutura-Atividade , Tiazinas/química , Tiazinas/farmacologia , Fatores de TempoRESUMO
Investigations on P(2)-P(3)-heterocyclic dipeptide surrogates directed towards identification of an orally bioavailable thrombin inhibitor led us to pursue novel classes of achiral, non-covalent P(1)-arginine derivatives. The design, synthesis, and biological activity of inhibitors NC1-NC30 that feature three classes of monocyclic P(1)-arginine surrogates will be disclosed: (1) (hetero)aromatic amidines, amines and hydroxyamidines, (2) 2-aminopyrazines, and (3) 2-aminopyrimidines and 2-aminotetrahydropyrimidines.
Assuntos
Antitrombinas/química , Antitrombinas/farmacologia , Arginina/química , Compostos Heterocíclicos/química , Animais , Antitrombinas/síntese química , Cães , Relação Estrutura-AtividadeRESUMO
Novel, potent, and highly selective classes of thrombin inhibitors were identified, which resulted from judicious combination of P4-aromatics and P2-P3-heterocyclic dipeptide surrogates with weakly basic (calcd pKa approximately non-basic-8.6) bicyclic P1-arginine mimics. The design, synthesis, and biological activity of achiral, non-covalent, orally bioavailable inhibitors NC1-NC44 featuring P1-indazoles, benzimidazoles, indoles, benzotriazoles, and aminobenzisoxazoles is disclosed.