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1.
Arthritis Rheumatol ; 69(10): 1949-1959, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28622463

RESUMO

OBJECTIVE: JAK inhibitors have shown efficacy in rheumatoid arthritis (RA). We undertook this study to test our hypothesis that selective inhibition of JAK-1 would combine good efficacy with a better safety profile compared with less selective JAK inhibitors. METHODS: In two 4-week exploratory, double-blind, placebo-controlled phase IIa trials, 127 RA patients with an insufficient response to methotrexate (MTX) received filgotinib (GLPG0634, GS-6034) oral capsules (100 mg twice daily or 30, 75, 150, 200, or 300 mg once daily) or placebo, added onto a stable regimen of MTX, to evaluate safety, efficacy, pharmacokinetics (PK), and pharmacodynamics (PD) of filgotinib. The primary efficacy end point was the number and percentage of patients in each treatment group meeting the American College of Rheumatology 20% improvement criteria (achieving an ACR20 response) at week 4. RESULTS: Treatment with filgotinib at 75-300 mg met the primary end point and showed early onset of efficacy. ACR20 response rates progressively increased to week 4, and the Disease Activity Score in 28 joints using the C-reactive protein (CRP) level decreased. Marked and sustained improvements were observed in serum CRP level and other PD markers. The PK of filgotinib and its major metabolite was dose proportional over the 30-300 mg range. Early side effects seen with other less selective JAK inhibitors were not observed (e.g., there was no worsening of anemia [JAK-2 inhibition related], no effects on liver transaminases, and no increase in low-density lipoprotein or total cholesterol). A limited decrease in neutrophils without neutropenia was consistent with immunomodulatory effects through JAK-1 inhibition. There were no infections. Overall, filgotinib was well tolerated. Events related to study drug were mild or moderate and transient during therapy, and the most common such event was nausea. CONCLUSION: Selective inhibition of JAK-1 with filgotinib shows initial efficacy in RA with an encouraging safety profile in these exploratory studies.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Janus Quinase 1/antagonistas & inibidores , Piridinas/administração & dosagem , Triazóis/administração & dosagem , Adulto , Idoso , Antirreumáticos/uso terapêutico , Artrite Reumatoide/imunologia , Artrite Reumatoide/fisiopatologia , Proteína C-Reativa/imunologia , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Piridinas/farmacocinética , Piridinas/uso terapêutico , Resultado do Tratamento , Triazóis/farmacocinética , Triazóis/uso terapêutico , Adulto Jovem
2.
Br J Clin Pharmacol ; 82(1): 139-48, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26852904

RESUMO

AIMS: Free fatty acids (FFA) can act as direct signalling molecules through activation of several membrane-bound G-protein coupled receptors. The FFA2 receptor (known as GPR43) is activated by short chain fatty acids (SCFA) such as acetate and has been shown to play a major role in SCFA-induced neutrophil activation and migration and to contribute in the development and control of inflammation. GLPG0974 is a potent and selective antagonist of the human FFA2. The main objectives of the two phase 1 trials were to characterize the safety, tolerability, pharmacokinetics and pharmacodynamics of GLPG0974. METHODS: Two consecutive randomized, double-blind, placebo-controlled, single centre trials in healthy subjects were performed. In the first, GLPG0974 was administered as single doses up to 250 mg and in the second, multiple daily doses up to 400 mg for 14 days were evaluated. Non-compartmental analysis was used to determine GLPG0974 pharmacokinetics while target engagement was investigated through the inhibition of neutrophils in acetate-simulated whole blood samples using surface expression of CD11b activated epitope as a marker of neutrophil activation. RESULTS: The investigation of safety/tolerability and pharmacokinetics in the early development phase showed that GLPG0974 was safe and well tolerated up to a daily dose of 400 mg. GLPG0974 showed good and dose proportional exposure up to 400 mg daily as well as a substantial and sustained inhibition of acetate-stimulated neutrophil activation. CONCLUSION: Based on these results, a proof-of-concept study was initiated to evaluate the safety, tolerability and efficacy of GLPG0974 in patients with mild to moderate ulcerative colitis.


Assuntos
Butiratos/administração & dosagem , Ativação de Neutrófilo/efeitos dos fármacos , Receptores de Superfície Celular/antagonistas & inibidores , Tiofenos/administração & dosagem , Adolescente , Adulto , Butiratos/farmacocinética , Butiratos/farmacologia , Movimento Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Tiofenos/farmacocinética , Tiofenos/farmacologia , Adulto Jovem
3.
Drug Metab Lett ; 10(1): 38-48, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26693854

RESUMO

OBJECTIVE: The selective Janus kinase 1 inhibitor filgotinib (GLPG0634), which is currently in clinical development for the treatment of rheumatoid arthritis (RA) and Crohn's disease, demonstrated encouraging safety and efficacy profiles in RA patients after 4 weeks of daily dosing. As RA patients might be treated with multiple medications simultaneously, possible drug-drug interactions of filgotinib with cytochrome P450 enzymes and with key drug transporters were evaluated in vitro and in clinical studies. METHODS: The enzymes involved in filgotinib's metabolism and the potential interactions of the parent and its active major metabolite with drug-metabolizing enzymes and drug transporters, were identified using recombinant enzymes, human microsomes, and cell systems. Furthermore, filgotinib's interaction potential with CYP3A4 was examined in an open-label study in healthy volunteers, which evaluated the impact of filgotinib co-administration on the CYP3A4-sensitive substrate midazolam. The potential interaction with the common RA drug methotrexate was investigated in a clinical study in RA patients. RESULTS: In vitro, filgotinib and its active metabolite at clinically relevant concentrations did not interact with cytochrome P450 enzymes and uridine 5'-diphospho-glucuronosyltransferases, and did not inhibit key drug transporters. In the clinic, a lack of relevant pharmacokinetic drug interactions by filgotinib and its active metabolite with substrates of CYP3A4, as well as with organic anion transporters involved in methotrexate elimination were found. CONCLUSION: the collective in vivo and in vitro data on drug-metabolizing enzymes and on key drug transporters, support co-administration of filgotinib with commonly used RA drugs to patients without the need for dose adjustments.


Assuntos
Antirreumáticos/farmacocinética , Janus Quinase 1/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacocinética , Piridinas/farmacocinética , Triazóis/farmacocinética , Adulto , Animais , Antirreumáticos/administração & dosagem , Antirreumáticos/efeitos adversos , Biotransformação , Células CHO , Cricetulus , Citocromo P-450 CYP3A/metabolismo , Inibidores das Enzimas do Citocromo P-450/farmacologia , Interações Medicamentosas , Glucuronosiltransferase/metabolismo , Humanos , Janus Quinase 1/metabolismo , Masculino , Proteínas de Membrana Transportadoras/efeitos dos fármacos , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Metotrexato/administração & dosagem , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Midazolam/metabolismo , Pessoa de Meia-Idade , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/efeitos adversos , Piridinas/administração & dosagem , Piridinas/efeitos adversos , Proteínas Recombinantes/metabolismo , Medição de Risco , Especificidade por Substrato , Transfecção , Triazóis/administração & dosagem , Triazóis/efeitos adversos
4.
Clin Pharmacokinet ; 54(8): 859-74, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25681059

RESUMO

BACKGROUND AND OBJECTIVES: Filgotinib (GLPG0634) is a selective inhibitor of Janus kinase 1 (JAK1) currently in development for the treatment of rheumatoid arthritis and Crohn's disease. While less selective JAK inhibitors have shown long-term efficacy in treating inflammatory conditions, this was accompanied by dose-limiting side effects. Here, we describe the pharmacokinetics of filgotinib and its active metabolite in healthy volunteers and the use of pharmacokinetic-pharmacodynamic modeling and simulation to support dose selection for phase IIB in patients with rheumatoid arthritis. METHODS: Two trials were conducted in healthy male volunteers. In the first trial, filgotinib was administered as single doses from 10 mg up to multiple daily doses of 200 mg. In the second trial, daily doses of 300 and 450 mg for 10 days were evaluated. Non-compartmental analysis was used to determine individual pharmacokinetic parameters for filgotinib and its metabolite. The overall pharmacodynamic activity for the two moieties was assessed in whole blood using interleukin-6-induced phosphorylation of signal-transducer and activator of transcription 1 as a biomarker for JAK1 activity. These data were used to conduct non-linear mixed-effects modeling to investigate a pharmacokinetic/pharmacodynamic relationship. RESULTS: Modeling and simulation on the basis of early clinical data suggest that the pharmacokinetics of filgotinib are dose proportional up to 200 mg, in agreement with observed data, and support that both filgotinib and its metabolite contribute to its pharmacodynamic effects. Simulation of biomarker response supports that the maximum pharmacodynamic effect is reached at a daily dose of 200 mg filgotinib. CONCLUSION: Based on these results, a daily dose range up to 200 mg has been selected for phase IIB dose-finding studies in patients with rheumatoid arthritis.


Assuntos
Antirreumáticos/administração & dosagem , Antirreumáticos/farmacocinética , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Piridinas/administração & dosagem , Piridinas/farmacocinética , Triazóis/administração & dosagem , Triazóis/farmacocinética , Adulto , Artrite Reumatoide/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Voluntários Saudáveis , Humanos , Janus Quinase 1/antagonistas & inibidores , Janus Quinase 1/metabolismo , Masculino , Pessoa de Meia-Idade , Fosforilação/efeitos dos fármacos , Piridinas/sangue , Triazóis/sangue
5.
J Immunol ; 191(7): 3568-77, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24006460

RESUMO

The JAKs receive continued interest as therapeutic targets for autoimmune, inflammatory, and oncological diseases. JAKs play critical roles in the development and biology of the hematopoietic system, as evidenced by mouse and human genetics. JAK1 is critical for the signal transduction of many type I and type II inflammatory cytokine receptors. In a search for JAK small molecule inhibitors, GLPG0634 was identified as a lead compound belonging to a novel class of JAK inhibitors. It displayed a JAK1/JAK2 inhibitor profile in biochemical assays, but subsequent studies in cellular and whole blood assays revealed a selectivity of ∼30-fold for JAK1- over JAK2-dependent signaling. GLPG0634 dose-dependently inhibited Th1 and Th2 differentiation and to a lesser extent the differentiation of Th17 cells in vitro. GLPG0634 was well exposed in rodents upon oral dosing, and exposure levels correlated with repression of Mx2 expression in leukocytes. Oral dosing of GLPG0634 in a therapeutic set-up in a collagen-induced arthritis model in rodents resulted in a significant dose-dependent reduction of the disease progression. Paw swelling, bone and cartilage degradation, and levels of inflammatory cytokines were reduced by GLPG0634 treatment. Efficacy of GLPG0634 in the collagen-induced arthritis models was comparable to the results obtained with etanercept. In conclusion, the JAK1 selective inhibitor GLPG0634 is a promising novel therapeutic with potential for oral treatment of rheumatoid arthritis and possibly other immune-inflammatory diseases.


Assuntos
Inflamação/metabolismo , Janus Quinase 1/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Triazóis/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Inativação Gênica , Humanos , Inflamação/tratamento farmacológico , Concentração Inibidora 50 , Interleucina-6/farmacologia , Janus Quinase 1/genética , Janus Quinase 1/metabolismo , Masculino , Camundongos , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/administração & dosagem , Piridinas/administração & dosagem , Ratos , Fator de Transcrição STAT1/metabolismo , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/imunologia , Triazóis/administração & dosagem
6.
Eur J Pharm Sci ; 41(2): 193-200, 2010 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-20685614

RESUMO

Various formulations for combination of the anti-HIV protease inhibitor darunavir (DRV) and TMC41629, a pharmacokinetic booster for DRV, were studied. TMC41629 (a BCS-IV compound) was formulated in capsules, as polyethylene glycol 400 (PEG400) solution, binary or ternary self-microemulsifying drug delivery system (SMEDDS), inclusion complex with hydroxypropyl-beta-cyclodextrin (HPbetaCD) or polyvinylpyrrolidone-co-vinylacetate 64 (PVP/VA64) extrudate. In addition, tablets were prepared using unmilled or micronized powder and a disintegrant. On co-administration with DRV tablets in dogs, DRV plasma concentration levels were boosted by TMC41629, the PVP/VA64 extrudate achieving the highest DRV levels (2-fold increase). Yet, with extrudate prepared with both compounds, no boosting effect was observed, likely due to transition of DRV from crystalline solvate to amorphous state. Therefore, a co-formulation, combining DRV as crystalline solvate with amorphous TMC41629, was developed. DRV/kappa-carrageenan 80/20% (w/w) beads coated with TMC41629 released at least 80% within 1h in 0.01M HCl with 0.5% sodium lauryl sulphate, TMC41629 dissolving faster than DRV. In dogs, the DRV exposure increased 2.7-fold with the TMC41629-coated beads relative to DRV alone, yet remained lower, but less variable, than following co-administration as separate formulations. Coating of TMC41629 on DRV/kappa-carrageenan beads is a suitable technique for co-formulation, whereby TMC41629 can function as a booster of DRV.


Assuntos
Inibidores da Protease de HIV/administração & dosagem , Sulfonamidas/administração & dosagem , Animais , Química Farmacêutica , Darunavir , Cães , Inibidores da Protease de HIV/farmacocinética , Sulfonamidas/farmacocinética , Comprimidos
7.
Antimicrob Agents Chemother ; 54(5): 2042-50, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20160045

RESUMO

The next-generation human immunodeficiency virus type 1 (HIV-1) nonnucleoside reverse transcriptase inhibitor rilpivirine (TMC278) was administered in rats and dogs as single intramuscular (IM) or subcutaneous (SC) injections, formulated as a 200-nm nanosuspension. The plasma pharmacokinetics, injection site concentrations, disposition to lymphoid tissues, and tolerability were evaluated in support of its potential use as a once-monthly antiretroviral agent in humans. Rilpivirine plasma concentration-time profiles showed sustained and dose-proportional release over 2 months in rats and over 6 months in dogs. The absolute bioavailability approached 100%, indicating a complete release from the depot, in spite of rilpivirine concentrations still being high at the injection site(s) 3 months after administration in dogs. For both species, IM administration was associated with higher initial peak plasma concentrations and a more rapid washout than SC administration, which resulted in a stable plasma-concentration profile over at least 6 weeks in dogs. The rilpivirine concentrations in the lymph nodes draining the IM injection site exceeded the plasma concentrations by over 100-fold 1 month after administration, while the concentrations in the lymphoid tissues decreased to 3- to 6-fold the plasma concentrations beyond 3 months. These observations suggest uptake of nanoparticles by macrophages, which generates secondary depots in these lymph nodes. Both SC and IM injections were generally well tolerated and safe, with observations of a transient inflammatory response at the injection site. The findings support clinical investigations of rilpivirine nanosuspension as a long-acting formulation to improve adherence during antiretroviral therapy and for preexposure prophylaxis.


Assuntos
Antirretrovirais/farmacocinética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , HIV-1 , Nitrilas/farmacocinética , Pirimidinas/farmacocinética , Animais , Antirretrovirais/sangue , Cães , Feminino , Injeções Intramusculares , Injeções Subcutâneas , Linfonodos/metabolismo , Linfócitos/metabolismo , Masculino , Músculo Esquelético/metabolismo , Nanoestruturas , Nitrilas/sangue , Pirimidinas/sangue , Ratos , Ratos Sprague-Dawley , Rilpivirina , Pele/metabolismo , Fator Tímico Circulante/metabolismo
8.
Gastroenterology ; 138(3): 913-21, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19852962

RESUMO

BACKGROUND & AIMS: The search for targeted anti-hepatitis C virus (HCV) drugs is driven by the adverse effect profile and limited efficacy of the current standard of care (pegylated interferon-alpha/ribavirin). In a first-in-human trial, we tested the safety, tolerability, and pharmacokinetics of the macrocyclic HCV NS3/4A protease inhibitor TMC435 in healthy volunteers, followed by HCV genotype 1-infected patients to assess antiviral activity. METHODS: The TMC435350-C101 study was a phase I, randomized, double-blind, placebo-controlled trial in 49 healthy volunteers, followed by an open-label, nonplacebo-controlled panel in 6 genotype 1 hepatitis C patients. Healthy volunteers received oral, single, ascending doses (up to 600 mg) or 5-day multiple ascending doses (200 mg twice daily or 100, 200, or 400 mg once daily). Patients received 200 mg once daily for 5 days. Pharmacokinetics and safety were evaluated for all panels, and plasma HCV-RNA levels were determined in patients. RESULTS: There were no serious adverse events, no grade 3 reactions, and no treatment-related discontinuations; pharmacokinetics supported a once daily dosing regimen. Plasma HCV-RNA levels dropped rapidly in all patients, with a median maximal reduction of 3.9-log(10) IU/mL and a median of 6 days to maximal reduction. The initial steep reduction of HCV-RNA (median 3.5-log(10) IU/mL at day 3) was followed by a more gradual decline that was maintained over the dosing period. No viral breakthroughs (>1-log(10) IU/mL HCV-RNA increase from nadir) were observed during treatment nor in the 3 days posttreatment; HCV-RNA returned to pretreatment levels by week 4. CONCLUSIONS: Once daily TMC435 given orally was generally safe and well tolerated and demonstrated potent antiviral activity.


Assuntos
Antivirais/administração & dosagem , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Compostos Heterocíclicos com 3 Anéis/administração & dosagem , Inibidores de Proteases/administração & dosagem , RNA Viral/sangue , Sulfonamidas/administração & dosagem , Carga Viral/efeitos dos fármacos , Proteínas não Estruturais Virais/antagonistas & inibidores , Administração Oral , Adulto , Antivirais/efeitos adversos , Antivirais/farmacocinética , DNA Viral/análise , Método Duplo-Cego , Esquema de Medicação , Feminino , Genótipo , Hepacivirus/enzimologia , Hepacivirus/genética , Hepatite C/diagnóstico , Compostos Heterocíclicos com 3 Anéis/efeitos adversos , Compostos Heterocíclicos com 3 Anéis/farmacocinética , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores de Proteases/efeitos adversos , Inibidores de Proteases/farmacocinética , Simeprevir , Sulfonamidas/efeitos adversos , Sulfonamidas/farmacocinética , Fatores de Tempo , Resultado do Tratamento , Proteínas não Estruturais Virais/genética , Adulto Jovem
9.
Eur J Pharm Biopharm ; 72(3): 614-20, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19303929

RESUMO

The aim of this study was to produce pellet formulations containing a high drug load (80%) of the poorly soluble HIV-protease inhibitor darunavir, using wet extrusion/spheronization with kappa-carrageenan or microcrystalline cellulose (MCC) as pelletization aid. Drug release was assessed in vitro by a standardized paddle-dissolution test and in vivo by a single-dose pharmacokinetic study in dogs. Mean dissolution time (MDT) was 78.2+/-3.5 h from MCC pellets (1301+/-301 microm) and 6.1+/-0.7 min from kappa-carrageenan pellets (966+/-136 microm). In contrast to kappa-carrageenan pellets, MCC pellets did not disintegrate and showed a diffusion-controlled drug release. In line with the in vitro findings, the darunavir peak plasma levels and exposure after the administration of a 300 mg dose were more than 60-fold higher when formulated with kappa-carrageenan pellets when compared with MCC pellets, and 10-fold higher after co-administration with 10mg/kg of ritonavir. The relative bioavailability of darunavir versus the reference tablet (F(rel)) was 155% with kappa-carrageenan pellets and 2% with MCC pellets without ritonavir, while 78% and 9%, respectively, in presence of ritonavir. In conclusion, when compared with MCC pellets, the bioavailability of darunavir was substantially improved in kappa-carrageenan pellets, likely due to their better disintegration behavior.


Assuntos
Carragenina/farmacocinética , Celulose/farmacocinética , Implantes de Medicamento/farmacocinética , Sulfonamidas/farmacocinética , Animais , Disponibilidade Biológica , Carragenina/sangue , Celulose/sangue , Estudos Cross-Over , Darunavir , Cães , Masculino , Sulfonamidas/sangue
10.
Eur J Pharm Biopharm ; 72(3): 502-8, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19328850

RESUMO

Long-acting parenteral formulations of antiretrovirals could facilitate maintenance and prophylactic treatment in HIV. Using the poorly water- and oil-soluble non-nucleoside reverse transcriptase inhibitor (NNRTI) TMC278 (rilpivirine) as base or hydrochloride (HCl), nanosuspensions were prepared by wet milling (Elan NanoCrystal technology) in an aqueous carrier. Laser diffraction showed that the average particles size were (1) close to the targeted size proportionality (200-400-800 nm), with increasing distributions the larger the average particle size, and (2) were stable over 6 months. Following single-dose administration, the plasma concentration profiles showed sustained release of TMC278 over 3 months in dogs and 3 weeks in mice. On comparison of intramuscular and subcutaneous injection of 5mg/kg (200 nm) in dogs, the subcutaneous route resulted in the most stable plasma levels (constant at 25 ng/mL for 20 days, after which levels declined slowly to 1-3 ng/mL at 3 months); 200 nm nanosuspensions achieved higher and less variable plasma concentration profiles than 400 and 800 nm nanosuspensions. In mice, the pharmacokinetic profiles after a single 20mg/kg dose (200 nm) were similar with two different surfactants used (poloxamer 338, or d-alpha-tocopheryl polyethylene glycol 1000 succinate). In conclusion, this study provides proof-of-concept that 200-nm sized TMC278 nanosuspensions may act as long-acting injectable.


Assuntos
Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Nanopartículas/administração & dosagem , Nitrilas/administração & dosagem , Pirimidinas/administração & dosagem , Animais , Química Farmacêutica , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/farmacocinética , Cães , Feminino , Infecções por HIV/virologia , Transcriptase Reversa do HIV/antagonistas & inibidores , HIV-1/enzimologia , HIV-1/crescimento & desenvolvimento , Injeções Intramusculares , Injeções Subcutâneas , Masculino , Camundongos , Nanopartículas/química , Nitrilas/síntese química , Nitrilas/farmacocinética , Pirimidinas/síntese química , Pirimidinas/farmacocinética , Rilpivirina
11.
Eur J Pharm Biopharm ; 70(3): 853-60, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18657611

RESUMO

Powders for reconstitution of the next-generation non-nucleoside reverse transcriptase inhibitor (NNRTI) TMC278 with low water solubility were developed by using a spray-dry technology. Their flexible dosing ability makes them suitable for patients looking for a different approach for antiretroviral (ARV) therapy. The selection of formulation excipients was based on their potential to create and maintain supersaturation solubility of TMC278 in 0.01 M HCl. Suitable water-soluble carriers for TMC278 were selected by a supersaturation screening to formulate powders for reconstitution by spray-drying. The selected powders for reconstitution were compared to clinical tablets of TMC278.HCl, in vitro using dissolution and stability testing, and in vivo through administration to beagle dogs, fed immediately after dosing. The spray-dried powders for reconstitution made up of TMC278/PVP-VA 64 1:9 (w/w) and TMC278/PVP-VA 64/Cremophor EL 1:8.5:0.5 (w/w/w) showed ease of suspendability, nearly complete dissolution of the drug and acceptable stability after one month storage at 25 and 40 degrees C. In dogs, TMC278 was more slowly absorbed from tablets than from the suspended powders for reconstitution. Compared to the tablet, the relative bioavailability obtained with the powders ranged between 69% and 89% for TMC278/PVP-VA 64 1:9 (w/w) and between 85% and 157% for TMC278/PVP-VA 64/Cremophor EL 1:8.5:0.5 (w/w/w). The absence of differences in vivo and in vitro between the powders made an eventual choice very difficult, yet their advantageous in vivo behaviour and flexible dosing possibility may provide a starting point for paediatric formulations.


Assuntos
Fármacos Anti-HIV/química , Excipientes/química , Transcriptase Reversa do HIV/antagonistas & inibidores , Nitrilas/química , Pirimidinas/química , Inibidores da Transcriptase Reversa/química , Administração Oral , Animais , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/farmacocinética , Disponibilidade Biológica , Química Farmacêutica , Cães , Portadores de Fármacos , Estabilidade de Medicamentos , Masculino , Nitrilas/administração & dosagem , Nitrilas/farmacocinética , Pós , Pirimidinas/administração & dosagem , Pirimidinas/farmacocinética , Inibidores da Transcriptase Reversa/administração & dosagem , Inibidores da Transcriptase Reversa/farmacocinética , Rilpivirina , Solubilidade , Comprimidos , Tecnologia Farmacêutica/métodos
12.
Drugs R D ; 5(5): 245-57, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15357624

RESUMO

OBJECTIVE: To investigate the important factors that determine the bioavailability and the antiviral activity of the diaryltriazine (DATA) and diarylpyrimidine (DAPY) non-nucleoside reverse transcriptase inhibitors (NNRTIs) of HIV-1 in animal species and humans using cell-based assays, physicochemical and computed parameters. METHODS: This naturalistic study included 15 parameters ranging from molecular mechanics calculations to phase I clinical trials. The calculated parameters were solvent-accessible surface area (SASA), polar surface area and Gibbs free energy of solvation. Physicochemical parameters comprised lipophilicity (octanol/water partition coefficient [cLogP]), ionisation constant (pKa), solubility and aggregate radius. Cell-based assays included human colonic adenocarcinoma cell (Caco-2) permeability (transepithelial transport), drug metabolism and antiviral activity (negative logarithm of the molar effective concentration inhibiting viral replication by 50% [pEC50]). Exposure was tested in rats, dogs and human volunteers. RESULTS: Of the 15 parameters, eight correlated consistently among one another. Exposure (area under the plasma concentration-time curve [AUC]) in humans correlated positively with that in rats (r = 1.00), with transepithelial transport (r = 0.83), lipophilicity (r = 0.60), ionisability (r = 0.89), hydrodynamic radius of aggregates (r = 0.66) and with antiviral activity (r = 0.61). Exposure in humans was also seen to correlate negatively with SASA (r = -0.89). No consistent correlation was found between exposure in dogs and the eight parameters. Of the 14 DATA/DAPY molecules, 11 form aggregates with radii between 34 and 100 nm. CONCLUSIONS: We observed correlations between exposure in humans with exposure in rats, transepithelial transport (Caco-2 cells), ionisability, lipophilicity, aggregate radius and SASA in the class of DATA/DAPY NNRTI compounds. The lipophilic DATA/DAPY compounds form aggregates. It can be assumed that absorption in the intestinal tract and endocytosis in infected cells of these lipophilic compounds are governed by the common phenomenon of aggregate formation. As the lymphatic system offers a pathway for intestinal uptake of aggregates, this may offer a therapeutic advantage in the treatment of HIV-1 infection. Although it was not the objective of the study, we found that the rat was a better in vivo model than the dog for the prediction of systemic exposure in this particular set of compounds.


Assuntos
Fármacos Anti-HIV/farmacocinética , Pirimidinas/farmacocinética , Inibidores da Transcriptase Reversa/farmacocinética , Triazinas/farmacocinética , Animais , Fármacos Anti-HIV/química , Área Sob a Curva , Disponibilidade Biológica , Células CACO-2 , Cães , HIV-1/efeitos dos fármacos , Humanos , Absorção Intestinal , Linfa/metabolismo , Modelos Moleculares , Pirimidinas/química , Ratos , Inibidores da Transcriptase Reversa/química , Relação Estrutura-Atividade , Triazinas/química
13.
AIDS ; 17(18): 2623-7, 2003 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-14685056

RESUMO

OBJECTIVE: TMC125, a next generation, non-nucleoside reverse transcriptase inhibitor (NNRTI), demonstrated a remarkable decline of plasma HIV-1 RNA during a phase IIa study. We compared the initial rate of decline of plasma HIV-1 RNA achieved by TMC125 monotherapy with that of a triple class, five-drug regimen, containing drugs from all three currently licensed classes (zidovudine, lamivudine, abacavir, indinavir and nevirapine). METHODS: The decline in plasma HIV-1 RNA of 12 HIV-1 infected, antiretroviral (ART) naive patients treated for 1 week with TMC125 monotherapy was compared with that observed in the ERA study (n = 11). The plasma HIV-1 RNA elimination rate constant was calculated based on at least four plasma HIV-1 RNA measurements during the first week of treatment (first-order elimination) and compared using the Student's t test. RESULTS: Median ages were 23 and 38 years for TMC125 and ERA patients, respectively (P = 0.001), median baseline plasma HIV-1 RNA levels were 4.2 and 4.8 log10 copies/ml (P = 0.001) and median baseline CD4 T-cell counts were 458 x 10(6) and 360 x 10(6) cells/l (P = 0.08). The median plasma HIV-1 RNA elimination rate constant was 0.68/day in TMC125 treated patients, and 0.56/day in ERA participants (P = 0.24). The median decline in plasma HIV-1 RNA after 7 days was 1.92 and 1.76 log10 copies (P = 0.77) and the median increase of CD4 T cells was 119 x 10(6) and 60 x 10(6) cells/l, respectively (P = 0.29). CONCLUSION: Monotherapy with TMC125 in ART-naive, HIV-1-infected individuals resulted in a similar rate of decline of plasma HIV-1 RNA during 1 week of therapy as therapy with a five-drug regimen.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , HIV-1 , Piridazinas/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Adulto , Contagem de Linfócito CD4 , Didesoxinucleosídeos/uso terapêutico , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Infecções por HIV/sangue , Inibidores da Protease de HIV/uso terapêutico , Humanos , Indinavir/uso terapêutico , Lamivudina/uso terapêutico , Masculino , Nevirapina/uso terapêutico , Nitrilas , Pirimidinas , RNA Viral/sangue , Resultado do Tratamento , Zidovudina/uso terapêutico
14.
AIDS ; 17(17): 2487-94, 2003 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-14600520

RESUMO

OBJECTIVE: To evaluate antiviral activity, tolerability, safety and pharmacokinetics of treatment with TMC125 (a non-nucleoside reverse transcriptase inhibitor), 900 mg twice daily for 7 days. DESIGN: Randomized, double-blind, placebo-controlled, phase IIA clinical trial. SETTING: Two hospital clinics in Moscow and St Petersburg, Russian Federation. PARTICIPANTS: Nineteen antiretroviral-naive, HIV-1-infected subjects. INTERVENTIONS: Randomization (2:1) was to twice daily treatment with either 900 mg TMC125 or matched placebo as monotherapy for 7 days. MAIN OUTCOME MEASURES: Change in plasma HIV-1 RNA from baseline values (primary); change in CD4 cell counts from baseline, and evaluation of safety, tolerability and pharmacokinetics of TMC125 treatment (secondary). RESULTS: A mean decrease from baseline in plasma HIV-1 RNA of 1.99 log10 copies/ml and 0.06 log10 copies/ml was achieved after 7 days in the TMC125 and placebo groups, respectively (P < 0.001). Plasma viral daily decay rates of 0.33 log10 copies/ml and 0.02 log10 copies/ml were observed in the TMC125 and placebo groups, respectively (P < 0.001). A steady-state plasma concentration of TMC125 was attained within 5 days of treatment with a mean minimum concentration of 246 ng/ml and a mean maximum concentration of 419 ng/ml. The majority of subjects did not report any adverse events. No abnormalities consistent with changes in blood chemistry, haematology, urinalysis, electrocardiograph or vital signs were observed. CONCLUSIONS: TMC125 administered as monotherapy for 7 days yielded a 1.99 log10 copies/ml reduction in HIV-1 RNA in antiretroviral-naive, HIV-1-infected subjects. TMC125 was well tolerated and represents a promising and highly potent, next generation non-nucleoside reverse transcriptase inhibitor candidate.


Assuntos
Infecções por HIV/tratamento farmacológico , HIV-1 , Piridazinas/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Adulto , Contagem de Linfócito CD4 , Método Duplo-Cego , Farmacorresistência Viral , HIV-1/genética , Humanos , Masculino , Mutação , Nitrilas , Piridazinas/efeitos adversos , Piridazinas/farmacocinética , Pirimidinas , RNA Viral/sangue , Inibidores da Transcriptase Reversa/efeitos adversos , Inibidores da Transcriptase Reversa/farmacocinética , Resultado do Tratamento , Carga Viral
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