Avaliação pré-clínica em roedores do perfil farmacocinético de novo candidato a Leishmanicida lassbio-1736

Abstract

In this study, a method was developed and validated for HPLC-PDA determination LASSBio-1736 in rat plasma using diclofenac sodium as internal standard (IS). Liquid-liquid extraction was used to extract acetonitrile LASSBio-1736. The chromatographic separation was performed with Waters Spherisorb®S5 ODS2 C18 column (150 mm x 4.6 mm, 5μm), isocratic mobile phase consisting of Triethylamine 0.3% (pH 4), methanol and acetonitrile (45:15:40, v / v / v) with a flow rate of 1 mL/min. Both LASSBio-1736 and IS were eluted at 4.2 and 5 min, respectively. The lower limit of quantification was 0.2 μg/mL and linearity between 0.2 - 4 μg/mL, with r2> 0.99. The accuracy was > 90.5%. The relative standard deviation within and between days were < 6.19 and < 7.83%, respectively. The method showed sensitivity, linearity, precision, accuracy and selectivity needed to quantify LASSBio-1736 in preclinical pharmacokinetic studies. This study also investigated the plasma pharmacokinetics and distribution of LASSBio-1736 in Wistar rats. The pharmacokinetic LASSBio-1736 was investigated after intravenous dose administration (3.2 mg/kg) intraperitoneally and orally (12.6 mg/kg). The tissue distribution was evaluated after iv bolus dose administration. The results indicated an intravenous long half-life (24.3 ± 8.2 h) clearance 49.3 ± 9.8 mL/kg*h and the volume of distribution 1.16 ± 0.3 L/ kg. The oral route the half-life was 28.6 ± 4.6 h, clearance 49.7 ± 13 mL/kg*h and volume of distribution 1.47 ± 0.34 L/kg and bioavailability of 12%. The intraperitoneally half-life was 26 ± 8.9 h, clearance 58 ± 19.6 mL/kg*h and the volume of distribution 1.8 ± 0.8 L/kg and bioavailability of 38%were similar. The LASSBio-1736 showed adequate tissue penetration for liver, spleen and skin. Based on the pharmacokinetic characteristics of other antileishmanial drugs and the decision proposition for pharmacokinetic studies for the discovery of drug candidates and continuing studies, the LASSBio-1736 has pharmacokinetic characteristics appropriate for a leishmanicide and new drug studies should be conducted to the interspecies scaling, and additional pharmacological and toxicological studies.