Characterizing the Physicochemical Properties of Two Weakly Basic Drugs and the Precipitates Obtained from Biorelevant Media

Pediatric Formulation Optimization Using a Rational Design: Exploring Amorphous Solid Dispersion Technology with Terbinafine Hydrochloride as a Case Study

Developing orally administered pediatric formulations presents significant challenges due to the unique characteristics of pediatric patients. Terbinafine hydrochloride (TER), a powerful antifungal agent, is effective against various fungal infections, including Tinea capitis, which is common in children. However, its low aqueous solubility necessitates innovative pharmaceutical strategies to enhance its effectiveness. This study describes a rational approach to selecting suitable carriers, approved for use in children, to increase the apparent solubility of TER and to guide the development of amorphous solid dispersions containing this drug. Assessments of solubility parameters, equilibrium solubility measurements, and calculations of pediatric dose numbers guided formulation development using theoretical and experimental methodologies. Carriers like Plasdone S-360 ULTRA®, HPMCAS L, and Soluplus® demonstrated favorable solubility parameter values with TER, indicating potential for drug solubilization. The solubility of TER was strongly dependent on pH. In buffer pH 6.5 containing 10% (w/v) of Soluplus®, TER presented the highest solubility value. The solid-state characterization techniques employed to assess the precipitate formed after equilibrium solubility studies during preformulation demonstrated that there were no phase transitions and no significant interactions between the drug and the evaluated carriers. Furthermore, the results demonstrate that Soluplus® achieved the lowest dose number (0.23) for pediatric patients over 6 years old. So, it was selected for preparing the amorphous solid dispersion via spray drying, which significantly enhanced the apparent solubility of TER while maintaining prolonged supersaturation, offering a promising alternative for developing solid formulations of this drug, particularly for pediatric patients, as it aims to improve oral bioavailability.

DrugMAP 2.0: molecular atlas and pharma-information of all drugs

The escalating costs and high failure rates have decelerated the pace of drug development, which amplifies the research interests in developing combinatorial/repurposed drugs and understanding off-target adverse drug reaction (ADR). In other words, it is demanded to delineate the molecular atlas and pharma-information for the combinatorial/repurposed drugs and off-target interactions. However, such invaluable data were inadequately covered by existing databases. In this study, a major update was thus conducted to the DrugMAP, which accumulated (a) 20831 combinatorial drugs and their interacting atlas involving 1583 pharmacologically important molecules; (b) 842 repurposed drugs and their interacting atlas with 795 molecules; (c) 3260 off-targets relevant to the ADRs of 2731 drugs and (d) various types of pharmaceutical information, including diverse ADMET properties, versatile diseases, and various ADRs/off-targets. With the growing demands for discovering combinatorial/repurposed therapies and the rapidly emerging interest in AI-based drug discovery, DrugMAP was highly expected to act as an indispensable supplement to existing databases facilitating drug discovery, which was accessible at: https://idrblab.org/drugmap/.

Key Factors for Improving Predictive Accuracy and Avoiding Overparameterization of the PBPK Absorption Model in Food Effect Studies of Weakly Basic Water-Insoluble Compounds in Immediate Release Formulations

Background/Objectives: Physiologically based pharmacokinetic (PBPK) absorption models are instrumental for assessing drug absorption prior to clinical food effect studies, though discrepancies in predictive and actual outcomes are observed. This study focused on immediate release formulations of weakly basic water-insoluble compounds, namely rivaroxaban, ticagrelor, and PB-201, to investigate factors that could improve the predictive accuracy of PBPK models regarding food effects. Methods: Comprehensive in vitro experimental results provided the basis for the development of mechanistic absorption models, which were then combined with mechanistic disposition models to predict the systemic exposure of the model drugs in both fasted and fed states. Results: The developed PBPK models showed moderate to high predictive accuracy for food effects in Caucasian populations. For the Chinese population, the ticagrelor model's initial overestimation of fed-state absorption was addressed by updating the permeability parameters from Caco-2 cell assays to those derived from parallel artificial membrane permeability assays in FaSSIF and FeSSIF media. This refinement was also applied to the rivaroxaban and ticagrelor models, leading to a more accurate representation of absorption in Caucasians. Conclusions: This study highlights the importance of apparent permeability in enhancing the predictive accuracy of PBPK absorption models for weakly basic water-insoluble compounds. Furthermore, the precipitation of PB-201 in the two-stage transfer experiments suggests that precipitation may not be a universal phenomenon for such compounds in vivo. Consequently, the precipitation rate constant, a theoretically essential parameter, should be determined based on experimental evidence to avoid overparameterization and ensure robust predictive accuracy of PBPK models.

Migration and Transformation of Taxane Allelochemicals in Soil

The migration and transformation of allelochemicals are important topics in the exploration of allelopathy. Current research on the migration of allelochemicals mostly uses soil column and thin layer methods and verifies it by sowing plant seeds. However, traditional methods inevitably ignore the flux caused by the movement of allelochemicals carried by water. In fact, the flux determines the amount of allelochemicals that directly affect plants. In this work, a method of microdialysis combined with a soil column and UPLC-MS/MS to detect the flux of allelochemicals was developed for the first time and successfully applied to the detection of five taxane allelochemicals in soil. Meanwhile, by adding taxane allelochemicals to the soil and detecting their transformation products using UPLC-MS/MS, the half-life of taxane in the soil was determined, and the transformation pathway of taxane allelochemicals in the soil was further speculated.