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1.
N Engl J Med ; 379(4): 352-362, 2018 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-30044938

RESUMO

BACKGROUND: Hereditary angioedema is a life-threatening illness caused by mutations in the gene encoding C1 inhibitor (also called C1 esterase inhibitor) that lead to overactivation of the kallikrein-bradykinin cascade. BCX7353 is a potent oral small-molecule inhibitor of plasma kallikrein with a pharmacokinetic and pharmacodynamic profile that may help prevent angioedema attacks. METHODS: In this international, three-part, dose-ranging, placebo-controlled trial, we evaluated four doses of BCX7353 (62.5 mg, 125 mg, 250 mg, and 350 mg once daily) for the prevention of angioedema attacks over a 28-day period. Patients with type I or II hereditary angioedema with a history of at least two angioedema attacks per month were randomly assigned to BCX7353 or placebo. The primary efficacy end point was the number of confirmed angioedema attacks. Key secondary end points included angioedema attacks according to anatomical location and quality of life. RESULTS: A total of 77 patients underwent randomization, 75 received BCX7353 or placebo, and 72 completed the trial. The rate of confirmed angioedema attacks was significantly lower among patients who received BCX7353 at daily doses of 125 mg or more than among those who received placebo, with a 73.8% difference at 125 mg (P<0.001). Significant benefits with respect to quality-of-life scores were observed in the 125-mg and 250-mg dose groups (P<0.05). Gastrointestinal adverse events, predominantly of grade 1, were the most commonly reported adverse events, particularly in the two highest BCX7353 dose groups. CONCLUSIONS: Once-daily oral administration of BCX7353 at a dose of 125 mg or more resulted in a significantly lower rate of attacks of hereditary angioedema than placebo. Mild gastrointestinal symptoms were the principal side effect. (Funded by BioCryst Pharmaceuticals; APeX-1 ClinicalTrials.gov number, NCT02870972 .).


Assuntos
Angioedemas Hereditários/prevenção & controle , Inibidores Enzimáticos/administração & dosagem , Calicreína Plasmática/antagonistas & inibidores , Administração Oral , Adulto , Idoso , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Inibidores Enzimáticos/efeitos adversos , Inibidores Enzimáticos/farmacocinética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida
4.
J Med Chem ; 57(5): 2033-46, 2014 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-24320933

RESUMO

A new class of highly potent NS5A inhibitors with an unsymmetric benzimidazole-difluorofluorene-imidazole core and distal [2.2.1]azabicyclic ring system was discovered. Optimization of antiviral potency and pharmacokinetics led to the identification of 39 (ledipasvir, GS-5885). Compound 39 (GT1a replicon EC50 = 31 pM) has an extended plasma half-life of 37-45 h in healthy volunteers and produces a rapid >3 log viral load reduction in monotherapy at oral doses of 3 mg or greater with once-daily dosing in genotype 1a HCV-infected patients. 39 has been shown to be safe and efficacious, with SVR12 rates up to 100% when used in combination with direct-acting antivirals having complementary mechanisms.


Assuntos
Antivirais/uso terapêutico , Benzimidazóis/uso terapêutico , Fluorenos/uso terapêutico , Hepatite C/tratamento farmacológico , Proteínas não Estruturais Virais/antagonistas & inibidores , Administração Oral , Animais , Antivirais/administração & dosagem , Antivirais/farmacocinética , Sequência de Bases , Benzimidazóis/farmacocinética , Benzimidazóis/farmacologia , Primers do DNA , Método Duplo-Cego , Fluorenos/farmacocinética , Fluorenos/farmacologia , Meia-Vida , Humanos , Macaca fascicularis , Masculino , Placebos , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
5.
J Hepatol ; 58(4): 663-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23183528

RESUMO

BACKGROUND & AIMS: Sofosbuvir (formerly GS-7977) is a pyrimidine nucleotide analog inhibitor of the hepatitis C virus (HCV) NS5B polymerase. We assessed the safety, tolerability, antiviral activity, and pharmacokinetics of sofosbuvir plus pegylated-interferon (PegIFN)/ribavirin (RBV) in a 28-day, dose-ranging trial in treatment-naïve patients infected with genotype 1 HCV. METHODS: In this double-blind study, 64 patients were randomized (1:1:1:1) to receive one of three once-daily doses of oral sofosbuvir (100, 200, or 400mg) or placebo plus PegIFN/RBV for 28 days, after which all patients continued to receive PegIFN/RBV alone for a further 44 weeks. RESULTS: Patients in the sofosbuvir/PegIFN/RBV groups experienced mean reductions in HCV RNA >5 log10 IU/ml (-5.3 for 100 mg, -5.1 for 200 mg and -5.3 for 400 mg) vs. -2.8 log10 IU/ml for placebo/PegIFN/RBV after 28 days. Rapid virologic response (RVR) rates were markedly higher after sofosbuvir treatment (88-94%) than placebo (21%), as were rates of sustained virologic response (SVR) at post-treatment Week 24 (56%, 83%, and 80% for sofosbuvir 100, 200, and 400 mg, respectively, vs. 43% for placebo). The number of patients experiencing virologic breakthrough and post-treatment relapse was higher in the sofosbuvir 100 mg group than sofosbuvir 200 and 400 mg groups. Sofosbuvir was well tolerated; the most frequent adverse events were fatigue and nausea. CONCLUSIONS: These results support further studies with sofosbuvir at 200 mg and 400 mg to determine the optimal dose and treatment duration of sofosbuvir in HCV genotype 1.


Assuntos
Antivirais/administração & dosagem , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Interferon-alfa/administração & dosagem , Polietilenoglicóis/administração & dosagem , Ribavirina/administração & dosagem , Uridina Monofosfato/análogos & derivados , Adulto , Antivirais/efeitos adversos , Antivirais/farmacocinética , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Hepacivirus/classificação , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/administração & dosagem , Sofosbuvir , Fatores de Tempo , Resultado do Tratamento , Uridina Monofosfato/administração & dosagem , Uridina Monofosfato/efeitos adversos , Uridina Monofosfato/farmacocinética , Adulto Jovem
6.
Antimicrob Agents Chemother ; 57(3): 1201-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23262999

RESUMO

To investigate the pharmacokinetics, safety, and tolerability of GS-9851 (formerly PSI-7851), a new nucleotide analog inhibitor of hepatitis C virus (HCV), we conducted a double-blind, parallel, placebo-controlled, randomized, single-ascending-dose study. Healthy subjects received oral doses of 25 to 800 mg GS-9851. Peak concentrations of GS-9851 in plasma were achieved more rapidly than those of the metabolites GS-566500 (formerly PSI-352707) and GS-331007 (formerly PSI-6206), with time to maximum concentration of drug in plasma (t(max)) values of 1.0 to 1.8 h, 1.5 to 3.0 h, and 3.0 to 6.0 h, respectively. The majority of systemic drug exposure was from the nucleoside GS-331007, with maximum concentration of drug in plasma (C(max)) and area under the concentration-time curve to the last measurable concentration (AUC(0-t)) values at least 7- and 41-fold higher, respectively, than those obtained for GS-9851 after adjusting for differences in molecular weight. The terminal elimination half-life (t(1/2)) of GS-331007 increased with the dose, achieving a t(1/2) of 25.7 h at 800 mg GS-9851. Dose proportionality was not observed for GS-331007. The majority of drug recovered in urine was in the form of GS-331007, with the percentage of this metabolite in urine samples ranging from 57% to 27% with increasing dose. GS-9851 was generally well tolerated, with no maximum tolerated dose identified. In conclusion, GS-9851 and its metabolites demonstrated a favorable pharmacokinetic profile consistent with once-daily dosing, and therefore, further clinical studies evaluating GS-9851 in HCV-infected patients are warranted.


Assuntos
Antivirais/farmacocinética , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Nucleotídeos/farmacocinética , RNA Viral/antagonistas & inibidores , Administração Oral , Adolescente , Adulto , Idoso , Antivirais/sangue , Antivirais/farmacologia , Área Sob a Curva , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Meia-Vida , Hepacivirus/crescimento & desenvolvimento , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Nucleotídeos/sangue , Nucleotídeos/farmacologia , Placebos , RNA Viral/biossíntese , Carga Viral/efeitos dos fármacos
7.
Antimicrob Agents Chemother ; 57(3): 1209-17, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23263000

RESUMO

We conducted this double-blind, parallel-group, placebo-controlled, randomized, multiple-ascending-dose study to assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of GS-9851 (formerly PSI-7851) in treatment-naïve patients infected with hepatitis C virus (HCV) genotype 1. Thirty-two patients received active doses up to 400 mg of GS-9851 once daily for 3 days. GS-9851 and the metabolite GS-566500 (formerly PSI-352707) were rapidly cleared from the plasma, with half-life (t(1/2)) values of approximately 1 h for GS-9851 and 3 h for GS-566500. Accumulation (21%) was observed only for GS-331007 (formerly PSI-6206) after multiple dosing. GS-331007 was the primary drug-related moiety in the plasma and urine. Increases in the GS-9851, GS-566500, and GS-331007 maximum concentrations in plasma (C(max)) and area under the concentration-time curve (AUC) were less than dose proportional, particularly at the highest doses. The decline in plasma HCV RNA levels was dose dependent, and a mean maximal change from the baseline of -1.95 log(10) IU/ml was obtained for 400 mg GS-9851, compared with -0.090 log(10) IU/ml for the placebo. Most patients had a decrease in HCV RNA of ≥1.0 log(10) IU/ml after 3 days' dosing with 400 mg GS-9851. No virologic resistance was observed. GS-9851 was generally well tolerated, with no notable differences in adverse event frequency across doses. The pharmacokinetic profile observed in this study was similar to that seen in a single-ascending-dose study in healthy subjects.


Assuntos
Antivirais/farmacocinética , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Nucleotídeos/farmacocinética , RNA Viral/antagonistas & inibidores , Administração Oral , Adolescente , Adulto , Idoso , Antivirais/sangue , Antivirais/farmacologia , Área Sob a Curva , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Meia-Vida , Hepacivirus/crescimento & desenvolvimento , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Nucleotídeos/sangue , Nucleotídeos/farmacologia , Placebos , RNA Viral/biossíntese , Carga Viral/efeitos dos fármacos
8.
Hepatology ; 55(2): 419-28, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22006541

RESUMO

UNLABELLED: In nonalcoholic steatohepatitis (NASH), the extent of hepatocyte apoptosis correlates with disease severity. Reducing hepatocyte apoptosis with the selective caspase inhibitor GS-9450 has a potential for altering the course of the liver disease. In this phase 2, double-blind study, 124 subjects with biopsy-proven NASH were randomized to once-daily placebo or 1, 5, 10, or 40 mg GS-9450 for 4 weeks. Absolute and percent changes from baseline in ALT levels, AST levels, and caspase-3-cleaved cytokeratin (CK)-18 fragments at week 4 were assessed by an analysis of covariance model with adjustment for baseline values. In the 40-mg group, mean (SD) ALT decreased by 47 (43) U/L from baseline to week 4 (P < 0.0001 versus placebo), and the proportion of subjects with normal ALT increased from 0% to 35% at week 4. In the 40-mg group, mean AST decreased by 13 U/L from baseline (not significant), and the proportion with normal AST increased from 20% at baseline to 48% at week 4. By week 4, mean CK-18 fragment levels had decreased to 393 (723) U/L in the GS-9450 10-mg group and 125 (212) U/L in the 40-mg group, but these reductions were not statistically significant. No serious adverse events were reported during treatment, and the percentage of subjects with at least one treatment-emergent grade 3 or 4 laboratory abnormality ranged from 11.5% to 17% across the GS-9450 treatment groups versus 35% in the placebo group. CONCLUSION: GS-9450 treatment induced significant reductions in ALT levels in NASH patients. Reductions in CK-18 fragment levels also occurred, although they were not statistically significant. At appropriate therapeutic indices, selective caspase inhibitors may be a promising treatment option in patients with NASH.


Assuntos
Inibidores de Caspase , Fígado Gorduroso/tratamento farmacológico , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Método Duplo-Cego , Fígado Gorduroso/sangue , Feminino , Humanos , Queratina-18/sangue , Masculino , Pessoa de Meia-Idade , Projetos Piloto
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