Lessons to be learnt from Leishmania studies

Leishmaniasis is a disease caused by infection with the protozoan parasite Leishmania, which is responsible for three main types of disease: cutaneous leishmaniasis, visceral leishmaniasis and mucocutaneous leishmaniasis based to the site of infection for the particular species. This presents a major challenge to successful drug treatment, as a drug must not only reach antileishmanial concentrations in infected macrophages, the parasites' host cell, but also reach infected cells in locations specific to the type of disease. In this paper we discuss how studies using Leishmania have contributed to our knowledge on how drug delivery systems can be used to improve drug efficacy and delivery

Formulation, preparation and in vitro - in vivo evaluation of compression-coated tablets for the colonic-specific release of ketoprofen

ABSTRACT The aim of this study was to formulate and prepare compression-coated tablets for colonic release (CR-tablets), and to evaluate the bioavailability of ketoprofen following the administration of a single dose from mini-tablets with immediate release (IR-tablets) compared to CR-tablets. CR-tablets were prepared based on time-controlled hydroxypropylmethylcellulose K100M inner compression-coating and pH-sensitive Eudragit® L 30D-55 outer film-coating. The clinical bioavailability study consisted of two periods, in which two formulations were administered to 6 volunteers, according to a randomized cross-over design. The apparent cumulative absorption amount of ketoprofen was estimated by plasma profile deconvolution. CR-tablets were able to delay ketoprofen’s release. Compared to IR-tablets used as reference, for the CR-tablets the maximum plasma concentration (Cmax) was lower (4920.33±1626.71 ng/mL vs. 9549.50±2156.12 ng/mL for IR-tablets) and the time needed to reach Cmax (tmax) was 5.33±1.63 h for CR-tablets vs. 1.33±0.88 h for IR-tablets. In vitro-in vivo comparison of the apparent cumulative absorption amount of ketoprofen showed similar values for the two formulations. Therefore, the obtained pharmacokinetic parameters and the in vitro-in vivo comparison demonstrated the reliability of the developed pharmaceutical system and the fact that it is able to avoid the release of ketoprofen in the first part of the digestive tract