New drug discovery strategies for the treatment of benznidazole-resistance in Trypanosoma cruzi, the causative agent of Chagas disease.

INTRODUCTION: Benznidazole, the drug of choice for treating Chagas Disease (CD), has significant limitations, such as poor cure efficacy, mainly in the chronic phase of CD, association with side effects, and parasite resistance. Understanding parasite resistance to benznidazole is crucial for developing new drugs to treat CD. AREAS COVERED: Here, the authors review the current understanding of the molecular basis of benznidazole resistance. Furthermore, they discuss the state-of-the-art methods and critical outcomes employed to evaluate the efficacy of potential drugs against T. cruzi, aiming to select better compounds likely to succeed in the clinic. Finally, the authors describe the different strategies employed to overcome resistance to benznidazole and find effective new treatments for CD. EXPERT OPINION: Resistance to benznidazole is a complex phenomenon that occurs naturally among T. cruzi strains. The combination of compounds that inhibit different metabolic pathways of the parasite is an important strategy for developing a new chemotherapeutic protocol.

Chitosan as an Outstanding Polysaccharide Improving Health-Commodities of Humans and Environmental Protection.

Public health, production and preservation of food, development of environmentally friendly (cosmeto-)textiles and plastics, synthesis processes using green technology, and improvement of water quality, among other domains, can be controlled with the help of chitosan. It has been demonstrated that this biopolymer exhibits advantageous properties, such as biocompatibility, biodegradability, antimicrobial effect, mucoadhesive properties, film-forming capacity, elicitor of plant defenses, coagulant-flocculant ability, synergistic effect and adjuvant along with other substances and materials. In part, its versatility is attributed to the presence of ionizable and reactive primary amino groups that provide strong chemical interactions with small inorganic and organic substances, macromolecules, ions, and cell membranes/walls. Hence, chitosan has been used either to create new materials or to modify the properties of conventional materials applied on an industrial scale. Considering the relevance of strategic topics around the world, this review integrates recent studies and key background information constructed by different researchers designing chitosan-based materials with potential applications in the aforementioned concerns.

First steps in the formulation of praziquantel nanosuspensions for pharmaceutical applications.

Praziquantel (PZQ), a broad spectrum anthelmintic drug, cannot be found in acceptable dosage forms for elderly patients, paediatric patients, and for veterinary use. In fact, very little has been done up to now in the formulation of liquid dosage forms, being they always formulated for parenteral administration. To beat this important challenge, it was accomplished a comprehensive analysis of the influence of two elementary physicochemical aspects, i.e. surface thermodynamic and electrokinetic properties, on the colloidal stability of PZQ nanosuspensions. The hydrophobic character of the drug, intensely determining the flocculation curves, was confirmed by the thermodynamic characterization. The electrophoretic characterization, in combination with the sedimentation and relative absorbance versus time curves, highlighted that the electrical double layer thickness and the surface charge can play an essential role in the stability of the pharmaceutical colloid. Finally, it was demonstrated that controlling the pH values and the incorporation of electrolytes can help in formulating PZQ aqueous nanosuspensions with appropriate stability and redispersibility behaviours for pharmaceutical use.

Acceptability of Multiple Uncoated Minitablets in Infants and Toddlers: A Randomized Controlled Trial.

OBJECTIVES: To assess the acceptability and swallowability of several minitablets when administered as a unit dose compared with an equivalent dose of syrup in children aged 6 months to 5 years. STUDY DESIGN: The acceptability and swallowability of multiple drug-free minitablets in comparison with glucose syrup was assessed in 372 children of 2 age groups (186 in age group 1 [6-23 months of age] and 186 in age group 2 [2-5 years of age]) in a randomized, 3-way, single administration cross-over study. Age group 1 received 25 minitablets, 100 minitablets, and 5 mL syrup. Age group 2 received 100 minitablets, 400 minitablets, and 10 mL syrup. RESULTS: Superiority was demonstrated in age group 1 for acceptability (25 minitablets, P < .017; 100 minitablets, P < .0001) and swallowability (25 minitablets and 100 minitablets, both P < .0001) compared with syrup. In age group 2, noninferiority of acceptability was found only for 400 minitablets (P < .0003), not for 100 minitablets. Subgroup analysis revealed a strong sequential effect. For swallowability, noninferiority could be demonstrated for 100 minitablets (P < .01) but not for 400 minitablets. CONCLUSIONS: Administration of ≥25 minitablets is well-tolerated, feasible, and safe in children aged from 6 months, and was superior to the equivalent dose of syrup. Children aged >1 year accept ≤400 minitablets even better than the equivalent dose of syrup. Minitablets open the perspective for introducing small-sized solid drug formulations for all children, thus, further shifting the paradigm from liquid toward small-sized solid drug formulations. TRIAL REGISTRATION: German Clinical Trials Register (DRKS): DRKS00008843.