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1.
Clin Pharmacol Ther ; 107(6): 1325-1333, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31868916

RESUMO

Fine-needle aspiration (FNA) for serial hepatic sampling may be an efficient and less invasive alternative to core needle biopsy (CNB), the current standard for liver tissue sampling. In this randomized, open-label trial in 31 participants with hepatitis C virus genotype 1 infection (NCT01678131/Merck protocol PN048), we evaluated the feasibility of using FNA to obtain human liver tissue samples appropriate for measuring hepatic pharmacokinetics (PK), using vaniprevir as a tool compound. The primary end point was successful retrieval of liver tissue specimens with measurable vaniprevir concentrations at two of three specified FNA time points. Twenty-nine patients met the primary end point and, therefore, were included in the PK analyses. Hepatic vaniprevir concentrations obtained with FNA were consistent with known vaniprevir PK properties. The shape of liver FNA and CNB concentration-time profiles were comparable. In conclusion, FNA may be effective for serial tissue sampling to assess hepatic drug exposure in patients with liver disease.


Assuntos
Antivirais/farmacocinética , Biópsia por Agulha Fina/métodos , Ciclopropanos/farmacocinética , Hepatite C Crônica/tratamento farmacológico , Isoindóis/farmacocinética , Lactamas Macrocíclicas/farmacocinética , Leucina/análogos & derivados , Fígado/metabolismo , Prolina/análogos & derivados , Sulfonamidas/farmacocinética , Adulto , Antivirais/administração & dosagem , Ciclopropanos/administração & dosagem , Feminino , Genótipo , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Isoindóis/administração & dosagem , Lactamas Macrocíclicas/administração & dosagem , Leucina/administração & dosagem , Leucina/farmacocinética , Fígado/virologia , Masculino , Pessoa de Meia-Idade , Prolina/administração & dosagem , Prolina/farmacocinética , Sulfonamidas/administração & dosagem , Distribuição Tecidual , Adulto Jovem
2.
Invest Ophthalmol Vis Sci ; 59(6): 2659-2669, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29847672

RESUMO

Purpose: Ligands for the proinflammatory C-C chemokine receptor types 2 and 5 (CCR2 and CCR5) are elevated in the eyes of patients with diabetic macular edema (DME). We evaluated the efficacy and safety of PF-04634817, an oral CCR2/5 dual antagonist, versus intravitreal ranibizumab, in adult subjects with DME. Methods: In this phase II, randomized, placebo-controlled, double-masked study, eligible subjects (≥18 years of age) had type 1 or 2 diabetes and DME with best-corrected visual acuity (BCVA) of 20/32 or worse (letter score ≤ 78), and up to 20/320 or better (≥24 letter score), in the study eye. Subjects were assigned randomly 1:1 to once-daily (QD) oral PF-04634817 200 mg plus masked sham therapy as placebo or monthly intravitreal ranibizumab 0.3/0.5 mg plus QD oral placebo. The primary objective was to evaluate the efficacy of PF-04634817 compared with ranibizumab in change from baseline in BCVA after 12 weeks in a noninferiority design. Noninferiority was based on BCVA 80% confidence interval (CI): there had to be a less than three letter loss in the PF-04634817 arm compared with the ranibizumab arm. Results: A total of 199 subjects were randomized. Least squares mean difference in change in BCVA from baseline to week 12 in the study eye for the PF-04634817 arm was -2.41 letters (80% CI: -3.91, -0.91; P = 0.04) compared with ranibizumab. PF-04634817 was well tolerated. Conclusions: Treatment with oral CCR2/5 receptor dual antagonist PF-04634817 was associated with a modest improvement in BCVA, but did not meet the predefined noninferiority criteria compared with intravitreal ranibizumab.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Compostos Azabicíclicos/uso terapêutico , Retinopatia Diabética/tratamento farmacológico , Edema Macular/tratamento farmacológico , Pirimidinas/uso terapêutico , Ranibizumab/administração & dosagem , Receptores CCR2/antagonistas & inibidores , Receptores CCR5/efeitos dos fármacos , Administração Oral , Retinopatia Diabética/diagnóstico por imagem , Retinopatia Diabética/fisiopatologia , Método Duplo-Cego , Feminino , Humanos , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/fisiologia
3.
Clin Ther ; 40(5): 704-718.e6, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29703432

RESUMO

PURPOSE: Elbasvir (MK-8742) and grazoprevir (MK-5172; Merck & Co, Inc, Kenilworth, New Jersey) are hepatitis C virus (HCV)-specific inhibitors of the nonstructural protein 5A phosphoprotein and the nonstructural protein 3/4A protease, respectively. The aims of these studies were to evaluate the antiviral activity and safety of different doses of elbasvir or grazoprevir each administered as monotherapy to participants infected with either HCV genotype (GT) 1 or GT3. METHODS: These 2 double-blind, randomized, placebo-controlled, sequential-panel, multiple ascending dose studies were conducted to assess the safety and pharmacodynamics of 5 days of once-daily elbasvir or 7 days of once-daily grazoprevir in adult male participants chronically infected with either HCV GT1 or GT3. FINDINGS: Oral administration of elbasvir or grazoprevir once daily exhibited potent antiviral activity in participants with chronic GT1 or GT3 HCV infections. HCV RNA levels declined rapidly (within 1 day for elbasvir and 2 days for grazoprevir). At 50 mg of elbasvir once daily, the mean maximum reductions in HCV RNA from baseline were 5.21, 4.17, and 3.12 log10 IU/mL for GT1b-, GT1a-, and GT3-infected participants, respectively. At 100 mg of grazoprevir once daily, the mean maximum reductions in HCV RNA from baseline were 4.74 and 2.64 log10 IU/mL for GT1- and GT3-infected participants. IMPLICATIONS: The results in the elbasvir monotherapy study showed that 10 to 50 mg of elbasvir was associated with a rapid decline in HCV viral load; the results in the grazoprevir monotherapy study suggest that doses of 50 mg of grazoprevir and higher are on the maximum response plateau of the dose-response curve for GT1-infected participants. The results of these proof-of-concept studies provided preliminary data for the selection of the dosages of elbasvir and grazoprevir to test in Phase II and III clinical studies. ClinicalTrials.gov identifiers: NCT00998985 (Protocol 5172-004) and NCT01532973 (Protocol 8742-002).


Assuntos
Antivirais/uso terapêutico , Benzofuranos/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Imidazóis/uso terapêutico , Quinoxalinas/uso terapêutico , Adulto , Amidas , Carbamatos , Ciclopropanos , Método Duplo-Cego , Genótipo , Hepacivirus/genética , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral , Sulfonamidas
4.
Ann Rheum Dis ; 77(4): 523-532, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29275332

RESUMO

OBJECTIVE: Interleukin (IL)-17A has emerged as pivotal in driving tissue pathology in immune-mediated inflammatory diseases. The role of IL-17F, sharing 50% sequence homology and overlapping biological function, remains less clear. We hypothesised that IL-17F, together with IL-17A, contributes to chronic tissue inflammation, and that dual neutralisation may lead to more profound suppression of inflammation than inhibition of IL-17A alone. METHODS: Preclinical experiments assessed the role of IL-17A and IL-17F in tissue inflammation using disease-relevant human cells. A placebo-controlled proof-of-concept (PoC) clinical trial randomised patients with psoriatic arthritis (PsA) to bimekizumab (n=39) or placebo (n=14). Safety, pharmacokinetics and clinical efficacy of multiple doses (weeks 0, 3, 6 (240 mg/160 mg/160 mg; 80 mg/40 mg/40 mg; 160 mg/80 mg/80 mg and 560 mg/320 mg/320 mg)) of bimekizumab, a humanised monoclonal IgG1 antibody neutralising both IL-17A and IL-17F, were investigated. RESULTS: IL-17F induced qualitatively similar inflammatory responses to IL-17A in skin and joint cells. Neutralisation of IL-17A and IL-17F with bimekizumab more effectively suppressed in vitro cytokine responses and neutrophil chemotaxis than inhibition of IL-17A or IL-17F alone. The PoC trial met both prespecified efficacy success criteria and showed rapid, profound responses in both joint and skin (pooled top three doses vs placebo at week 8: American College of Rheumatology 20% response criteria 80.0% vs 16.7% (posterior probability >99%); Psoriasis Area and Severity Index 100% response criteria 86.7% vs 0%), sustained to week 20, without unexpected safety signals. CONCLUSIONS: These data support IL-17F as a key driver of human chronic tissue inflammation and the rationale for dual neutralisation of IL-17A and IL-17F in PsA and related conditions. TRIAL REGISTRATION NUMBER: NCT02141763; Results.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Neutralizantes/imunologia , Artrite Psoriásica/tratamento farmacológico , Interleucina-17/imunologia , Adulto , Anticorpos Monoclonais Humanizados/imunologia , Artrite Psoriásica/imunologia , Método Duplo-Cego , Feminino , Humanos , Inflamação/tratamento farmacológico , Inflamação/imunologia , Interleucina-17/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Índice de Gravidade de Doença , Resultado do Tratamento
5.
PLoS One ; 12(12): e0187397, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29236711

RESUMO

The objective of this study was to compare the scope and the discriminative power of Dynamic Contrast Enhanced Magnetic Resonance Imaging (DCE-MRI) to those of semi-quantitative MRI scoring for evaluating treatments for rheumatoid arthritis (RA) in multicenter randomized clinical trials (RCTs). Sixty-one patients with active RA participated in a double-blind, parallel group, randomized, multicenter methodology study receiving infliximab or placebo through 14 weeks. The most symptomatic wrist and metacarpophalangeal joints (MCPs) were imaged using MRI. In addition to clinical assessments with DAS28(CRP), the severity of inflammation was measured as synovial leak of gadolinium based contrast agent (GBCA) using DCE-MRI (Ktrans, primary endpoint) at weeks 0, 2, 4, and 14. Two radiologists independently scored synovitis, osteitis and erosion using RA MRI Score (RAMRIS) and cartilage loss using a 9-point MRI scale (CARLOS). Infliximab showed greater decrease from baseline in DAS28(CRP), DCE-MRI Ktrans of wrist and MCP synovium, and RAMRIS synovitis and osteitis at all visits compared with placebo (p<0.001). Treatment effect sizes of infliximab therapy were similar for DAS28(CRP) (1.08; 90% CI (0.63-1.53)) and MRI inflammation endpoints: wrist Ktrans (1.00 (0.55-1.45)), RAMRIS synovitis (0.85 (0.38-1.28)) and RAMRIS osteitis (0.99 (0.52-1.43)). Damage measures of bone erosion (RAMRIS) and cartilage loss (CARLOS) were reduced with infliximab compared to with placebo at 14 weeks (p≤0.025). DCE-MRI and RAMRIS were equally sensitive and responsive to the anti-inflammatory effects of infliximab. RAMRIS and CARLOS showed suppression of erosion and cartilage loss, respectively, at 14 weeks. (ClinicalTrials.gov registration: NCT01313520).


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/tratamento farmacológico , Meios de Contraste , Mãos/diagnóstico por imagem , Infliximab/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Punho/diagnóstico por imagem , Adulto , Método Duplo-Cego , Feminino , Gadolínio/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Resultado do Tratamento
6.
Ann Rheum Dis ; 76(3): 534-542, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27672124

RESUMO

OBJECTIVES: This phase II trial evaluated the efficacy and safety of an interleukin (IL) 6 monoclonal antibody for systemic lupus erythematosus (SLE). METHODS: Patients with active disease were randomised to placebo or PF-04236921 10 mg, 50 mg or 200 mg, subcutaneously, every 8 weeks with stable background therapy. SLE Responder Index (SRI-4; primary end point) and British Isles Lupus Assessment Group-based Composite Lupus Assessment (BICLA) were assessed at week 24. Post hoc analysis identified an enriched population based upon planned univariate analyses. RESULTS: 183 patients received treatment (placebo, n=45; 10 mg, n=45; 50 mg, n=47; 200 mg, n=46). The 200 mg dose was discontinued due to safety findings and not included in the primary efficacy analysis. The SRI-4 response rates were not significant for any dose compared with placebo; however, the BICLA response rate was significant for 10 mg (p=0.026). The incidence of severe flares was significantly reduced with 10 mg (n=0) and 50 mg (n=2) combined versus placebo (n=8; p<0.01). In patients with greater baseline disease activity (enriched population), the SRI-4 (p=0.004) and BICLA (p=0.012) response rates were significantly different with 10 mg versus placebo. Four deaths (200 mg, n=3; 10 mg, n=1) occurred. The most frequently reported adverse events included headache, nausea and diarrhoea. CONCLUSIONS: PF-04236921 was not significantly different from placebo for the primary efficacy end point in patients with SLE. Evidence of an effect with 10 mg was seen in a post hoc analysis. Safety was acceptable for doses up to 50 mg as the 200 mg dose was discontinued due to safety findings. TRIAL REGISTRATION NUMBER: NCT01405196; Pre-results.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Interleucina-6/antagonistas & inibidores , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Adulto , Diarreia/induzido quimicamente , Feminino , Cefaleia/induzido quimicamente , Humanos , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Embolia Pulmonar/induzido quimicamente , Sepse/induzido quimicamente , Índice de Gravidade de Doença , Exacerbação dos Sintomas
7.
Diabetes Ther ; 4(2): 431-42, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24163113

RESUMO

INTRODUCTION: Saxagliptin, sitagliptin, and vildagliptin are dipeptidyl peptidase-4 (DPP-4) inhibitors widely approved for use in patients with type 2 diabetes. Using a crossover design, the present study compared trough levels of DPP-4 inhibition provided by these agents in a single cohort of patients with type 2 diabetes. METHODS: This was a randomized, placebo-controlled, open-label, five-period crossover study. Eligible patients were 18-65 years of age, either treatment-naïve or off prior antihyperglycemic agent therapy for at least 6 or 12 weeks (depending on the prior therapy), and had glycated hemoglobin (HbA1C) ≥6.5% and ≤10.0%. In separate study periods, patients received 5 mg saxagliptin q.d. (saxa-5), 100 mg sitagliptin q.d. (sita-100), 50 mg vildagliptin q.d. (vilda-50-q.d.), 50 mg vildagliptin b.i.d. (vilda-50-b.i.d.), or placebo for 5 days. The primary endpoint was trough %DPP-4 inhibition, derived by comparing DPP-4 activity 24 h after the Day-5 morning dose with predose activity in the same period and analyzed using a linear mixed-effects model with fixed-effects terms for treatment and period. RESULTS: Mean (range) baseline HbA1C was 7.4% (6.4-9.0%; N = 22). Least-squares (LS) mean trough %DPP-4 inhibition was 73.5%, 91.7%, 28.9%, 90.6%, and 3.5% after saxa-5, sita-100, vilda-50-q.d., vilda-50-b.i.d., and placebo, respectively. In patients treated with sita-100, the LS-mean difference in trough %DPP-4 inhibition was 18.2% greater than with saxa-5 (p < 0.001), 62.9% greater than with vilda-50-q.d. (p < 0.001), 1.1% greater than with vilda-50-b.i.d. (p = 0.128), and 87.8% greater than with placebo (p < 0.001). Mean %DPP-4 inhibition was nearly maximal at 12 h postdose regardless of active treatment. Thus, these between-group comparisons at trough primarily reflected differences in duration of action. Adverse events reported during the study were transient and mild or moderate in intensity. CONCLUSION: Once daily treatment with sitagliptin provided trough DPP-4 inhibition significantly greater than saxagliptin or vildagliptin administered once daily, and similar to that provided by vildagliptin administered twice daily.

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