Trends in rheumatic fever: clinical aspects and perspectives in prophylactic treatments

Introduction: Rheumatic fever (RF), a systemic illness that may occur following Group A beta-hemolytic streptococcal (GABHS) pharyngitis in children, is a major problem in countries with limited resources. Because of its long track record and low cost, an injection of benzathine penicillin G (BPG) suspension every 3 or 4 weeks has been used as secondary prophylaxis. Despite its excellent in vitro efficacy, the inability of BPG to eradicate GABHS has been frequently reported.Areas covered: This work reviews the possible causes of failure, as well as the inconvenience of the current prophylactic treatment of acute RF and suggests a new pharmacotherapeutic system that could replace the current one.Expert opinion: RF is a major problem concerning only countries with limited resources and could be considered as a neglected disease. The dose regimen using BPG suspension results in failures, which could be avoided by the use of nanocarrier-based systems. To meet this ultimate goal, the research should be transposed from the laboratory scale to an industrial and clinical application level. This research should be conducted to produce a pharmaceutical dosage form that will be commercially available, consumed by and affordable for patients. However, health, environmental and socioeconomic hazards should be considered

Understanding Drug Release Data through Thermodynamic Analysis

Understanding the factors that can modify the drug release profile of a drug from a Drug-Delivery-System (DDS) is a mandatory step to determine the effectiveness of new therapies. The aim of this study was to assess the Amphotericin-B (AmB) kinetic release profiles from polymeric systems with different compositions and geometries and to correlate these profiles with the thermodynamic parameters through mathematical modeling. Film casting and electrospinning techniques were used to compare behavior of films and fibers, respectively. Release profiles from the DDSs were performed, and the mathematical modeling of the data was carried out. Activation energy, enthalpy, entropy and Gibbs free energy of the drug release process were determined. AmB release profiles showed that the relationship to overcome the enthalpic barrier was PVA-fiber > PVA-film > PLA-fiber > PLA-film. Drug release kinetics from the fibers and the films were better fitted on the Peppas–Sahlin and Higuchi models, respectively. The thermodynamic parameters corroborate these findings, revealing that the AmB release from the evaluated systems was an endothermic and non-spontaneous process. Thermodynamic parameters can be used to explain the drug kinetic release profiles. Such an approach is of utmost importance for DDS containing insoluble compounds, such as AmB, which is associated with an erratic bioavailability

A Functional Wound Dressing as a Potential Treatment for Cutaneous Leishmaniasis

Cutaneous leishmaniasis (CL) is a parasitic disease characterized by progressive skin sores. Currently, treatments for CL are limited to parenteral administration of the drug, which presents severe adverse effects and low cure rates. Therefore, this study aimed to develop poly(vinyl-alcohol) (PVA) hydrogels containing Amphotericin B (AmB) intended for topical treatment of CL. Hydrogels were evaluated in vitro for their potential to eliminate promastigote forms of Leishmania spp., to prevent secondary infections, to maintain appropriate healing conditions, and to offer suitable biocompatibility. AmB was incorporated into the system in its non-crystalline state, allowing it to swell more and faster than the system without the drug. Furthermore, the AmB release profile showed a continuous and controlled behavior following Higuchi´s kinetic model. AmB-loaded-PVA-hydrogels (PVA−AmB) also showed efficient antifungal and leishmanicidal activity, no cytotoxic potential for VERO cells, microbial impermeability and water vapor permeability compatible with the healthy skin’s physiological needs. Indeed, these results revealed the potential of PVA−AmB to prevent secondary infections and to maintain a favorable environment for the healing process. Hence, these results suggest that PVA−AmB could be a suitable and efficient new therapeutic approach for the topical treatment of CL