RESUMO
This work describes an exploratory experimental and in silico study of the influence of polymorphism, particle size, and physiology on the pharmacokinetics of lercanidipine hydrochloride (LHC). Equilibrium and kinetic solubility studies were performed on LHC forms I and II, as a function of pH and buffer composition. GastroPlus® was used to evaluate the potential effect of solubility differences due to polymorphism, particle size, and physiological conditions, on the drug pharmacokinetics. The results indicated that solubilities of LHC polymorphs are strongly dependent on the composition and pH of the buffer media. The concentration ratio (CI/CII) is particularly large for chloride buffer (CI/CII = 3.3-3.9) and exhibits a slightly decreasing tendency with the pH increase for all other buffers. Based on solubility alone, a higher bioavailability of form I might be expected. However, exploratory PBPK simulations suggested that (i) under usual fasted (pH 1.3) and fed (pH 4.9) gastric conditions, the two polymorphs have similar bioavailability, regardless of the particle size; (ii) at high gastric pH in the fasted state (e.g., pH 3.0), the bioavailability of form II can be considerably lower than that of form I, unless the particle size is < 20 µm. This study demonstrates the importance of investigating the effect of the buffer nature when evaluating the solubility of ionizable polymorphic substances. It also showcases the benefits of using PBPK simulations, to assess the risk and pharmacokinetic relevance of different solubility and particle size between crystal forms, for diverse physiological conditions.
Assuntos
Di-Hidropiridinas/química , Disponibilidade Biológica , Di-Hidropiridinas/farmacocinética , Humanos , Concentração de Íons de Hidrogênio , Tamanho da Partícula , SolubilidadeRESUMO
This study evaluates the carvedilol-lercanidipine drug interaction, and the influence of chronic kidney disease (CKD) on both drugs. Patients with high blood pressure (8 with normal renal function [control] and 8 with CKD with estimated glomerular filtration rate categories of G3b to G5 [12-38 mL/min/1.73 m2 ]) were included and prescribed 3 different treatment regimens, a single oral dose of racemic carvedilol 25 mg (CAR), a single oral dose of racemic lercanidipine 20 mg (LER), and single oral doses of CAR plus LER. Blood samples were collected and variations in heart rate were assessed (using isometric exercise with handgrip) for up to 32 hours. Lercanidipine pharmacokinetics were not enantioselective, and were not affected by carvedilol and CKD. Carvedilol pharmacokinetics (data presented as median) were enantioselective with higher plasma exposure of (R)-(+)-carvedilol in both control (103.5 vs 46.0 ng â h/mL) and CKD (190.6 vs 98.9 ng â h/mL) groups. Lercanidipine increased the area under the plasma concentration-time curve of only (R)-(+)-carvedilol in the CKD group (190.6 vs 242.2 ng â h/mL) but not in the control group (103.5 vs 98.7 ng â h/mL). CKD increased plasma exposure (46.0 vs 98.9 ng â h/mL) and effect-compartment exposure (5.5 vs 20.9 ng â h/mL) to (S)-(-)-carvedilol, resulting in higher ß-adrenergic inhibition (10.0 vs 6.1 bpm). Therefore, carvedilol dose titration in CKD patients with estimated glomerular filtration rate categories of G3b to G5 should be initiated, with no more than half the dose used for patients with normal renal function.
Assuntos
Anti-Hipertensivos/farmacocinética , Anti-Hipertensivos/uso terapêutico , Carvedilol/farmacocinética , Carvedilol/uso terapêutico , Di-Hidropiridinas/farmacocinética , Di-Hidropiridinas/uso terapêutico , Insuficiência Renal Crônica/metabolismo , Administração Oral , Adulto , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/química , Carvedilol/administração & dosagem , Carvedilol/química , Estudos de Casos e Controles , Estudos Cross-Over , Sistema Enzimático do Citocromo P-450/metabolismo , Di-Hidropiridinas/administração & dosagem , Interações Medicamentosas , Feminino , Taxa de Filtração Glomerular , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológico , EstereoisomerismoRESUMO
Abstract Nonsteroidal anti-inflammatory drugs (NSAID) are among the aggressive factors causing gastric ulcer. They cause oxidative damage in the gastric tissue and lead to intracellular calcium deposition. Lercanidipine is a calcium channel blocker derived from the third generation dihydropyridine. The aim of this study is to analyse the effect of lercanidipine on indomethacin-induced gastric ulcers. A total of 24 albino Wistar male rats were divided into four groups; those who received indomethacin 25 mg/kg (IND), 5 mg mg/kg lercanidipine +25 mg/kg indomethacin (LC-5), 10 mg/kg lercanidipine+25mg/kg indomethacin (LC-10) and healthy rats who received 0.5 mL distilled water. Six hours after the application of indomethacin, the animals were sacrificed by high dose thiopental sodium. The stomachs of the animals were excised to perform a macroscopic analysis and the ulcerous region was measured on millimeter paper. All the stomachs were subjected to a biochemical analysis. Macroscopic analysis revealed hyperaemia on the gastric surface of the indomethacin group. Ulcerous tissues formed by oval, circular or irregular mucosal defects in varying diameters and depths were observed on the whole surface of the stomach. Hyperaemia was lower and ulcerous region was smaller in groups LC-5 and LC-10 compared to IND group. Malondialdehyde and myeloperoxidase levels were significantly lower and total glutathione and cyclooxygenase-1 activity were higher in groups LC-5 and LC-10. Lercanidipine did not change the cyclooxygenase-2 activity. Lercanidipine in doses 10 mg/kg is more effective compared to 5 mg/kg. Lercanidipinine can be useful in the treatment of NSAID-induced gastric damage.