Selecting appropriate excipients for paediatric dosage form - Paediatric excipients risk assessment (PERA) framework - Part 1.

Excipients are often the major component of the formulation that critically affect the dosage form, manufacturing process, product performance, stability and safety. They exert different roles and functions in a dosage form. Selecting excipients with appropriate safety and tolerability is a major hurdle in paediatric formulation development.

Paediatric excipient risk assessment (PERA) tool and application for selecting appropriate excipients for paediatric dosage forms - Part 2.

It is necessary to use a scientifically sound process for excipient risk evaluation, selection, and management in order to develop paediatric medicinal products that are both safe and effective. The "Paediatric Excipient Risk Assessment (PERA)" framework, which proposes a comprehensive approach by considering all relevant factors related to patient, dosage form, and excipient attributes, was developed and published as part 1 of this paper series, to enable the rational selection of excipients for paediatric medicinal products. This article is Part 2 of the series and presents the PERA tool that allows easy adoption of the PERA framework.

The Development of Minitablets for a Pediatric Dosage Form for a Combination Therapy.

Minitablets are an appealing option for an age-appropriate pediatric dosage form. In particular, for combination therapies where multiple active ingredients are dosed simultaneously, the use of minitablets will enable independent adjustments of each dose. The work presented describes the development of Compound A and Compound B minitablets for a combination therapy.

Producing Amorphous Solid Dispersions via Co-Precipitation and Spray Drying: Impact to Physicochemical and Biopharmaceutical Properties.

Many small-molecule active pharmaceutical ingredients (APIs) exhibit low aqueous solubility and benefit from generation of amorphous dispersions of the API and polymer to improve their dissolution properties. Spray drying and hot-melt extrusion are 2 common methods to produce these dispersions; however, for some systems, these approaches may not be optimal, and it would be beneficial to have an alternative route. Herein, amorphous solid dispersions of compound A, a low-solubility weak acid, and copovidone were made by conventional spray drying and co-precipitation.

Amorphous Solid Dispersions or Prodrugs: Complementary Strategies to Increase Drug Absorption.

Maximizing oral bioavailability of drug candidates represents a challenge in the pharmaceutical industry. In recent years, there has been an increase in the use of amorphous solid dispersions (ASDs) to address this issue, where a growing number of solid dispersion formulations have been introduced to the market. However, an increase in solubility or dissolution rate through ASD does not always result in sufficient improvement of oral absorption because solubility limitations may still exist at high doses.

Understanding the tendency of amorphous solid dispersions to undergo amorphous-amorphous phase separation in the presence of absorbed moisture.

Formulation of an amorphous solid dispersion (ASD) is one of the methods commonly considered to increase the bioavailability of a poorly water-soluble small-molecule active pharmaceutical ingredient (API). However, many factors have to be considered in designing an API-polymer system, including any potential changes to the physical stability of the API. In this study, the tendency of ASD systems containing a poorly water-soluble API and a polymer to undergo amorphous-amorphous phase separation was evaluated following exposure to moisture at increasing relative humidity.

Analysis of relationships between solid-state properties, counterion, and developability of pharmaceutical salts.

The solid-state properties of pharmaceutical salts, which are dependent on the counterion used to form the salt, are critical for successful development of a stable dosage form. In order to better understand the relationship between counterion and salt properties, 11 salts of procaine, which is a base, were synthesized and characterized using a variety of experimental and computational methods. Correlations between the various experimental and calculated physicochemical properties of the salts and counterions were probed.

Application of partial least-squares (PLS) modeling in quantifying drug crystallinity in amorphous solid dispersions.

Among the different experimental methods that can be used to quantify the evolution of drug crystallinity in polymer-containing amorphous solid dispersions, powder X-ray diffractometry (PXRD) is commonly considered as a frontline method. In order to achieve accurate quantification of the percent drug crystallinity in the system, calibration curves have to be constructed using appropriate calibration samples and calculation methods. This can be non-trivial in the case of partially crystalline solid dispersions where the calibration samples must capture the multiphase nature of the systems and the mathematical model must be robust enough to accommodate subtle and not so subtle changes in the diffractograms.

Effect of polymer hygroscopicity on the phase behavior of amorphous solid dispersions in the presence of moisture.

It has been previously observed that exposure to high relative humidity (RH) can induce amorphous-amorphous phase separation in solid dispersions composed of certain hydrophobic drugs and poly(vinylpyrrolidone) (PVP). The objective of this study was to investigate if this phenomenon occurred in solid dispersions prepared using less hygroscopic polymers. Drug-polymer miscibility was investigated before and after exposure to high RH using infrared (IR) spectroscopy and differential scanning calorimetry (DSC).

Effects of polymer type and storage relative humidity on the kinetics of felodipine crystallization from amorphous solid dispersions.

Purpose: The objective of this study was to investigate the effects of polymer type and storage relative humidity (RH) on the crystallization kinetics of felodipine from amorphous solid dispersions.

Methods: Crystallization of the model drug felodipine from amorphous solid dispersion samples containing poly(vinyl pyrrolidone) (PVP) and hypromellose acetate succinate (HPMCAS) were evaluated. Samples at three different drug-polymer weight ratios (10, 25, and 50 wt.

Evaluation of drug-polymer miscibility in amorphous solid dispersion systems.

Purpose: To evaluate drug-polymer miscibility behavior in four different drug-polymer amorphous solid dispersion systems, namely felodipine-poly(vinyl pyrrolidone) (PVP), nifedipine-PVP, ketoconazole-PVP, and felodipine-poly(acrylic acid) (PAA).

Materials And Methods: Amorphous solid dispersion samples were prepared at different drug-to-polymer ratios and analyzed using differential scanning calorimetry (DSC), mid-infrared (IR) spectroscopy, and powder X-ray diffractometry (PXRD). To help with interpretation of the IR spectra, principal components (PC) analysis was performed.

Phase behavior of poly(vinylpyrrolidone) containing amorphous solid dispersions in the presence of moisture.

The objective of this study was to investigate the phase behavior of amorphous solid dispersions composed of a hydrophobic drug and a hydrophilic polymer following exposure to elevated relative humidity. Infrared (IR) spectroscopy, differential scanning calorimetry (DSC) and moisture sorption analysis were performed on five model systems (nifedipine-poly(vinylpyrrolidone) (PVP), indomethacin-PVP, ketoprofen-PVP, droperidol-PVP, and pimozide-PVP) immediately after production of the amorphous solid dispersions and following storage at room temperature and elevated relative humidity. Complete miscibility between the drug and the polymer immediately after solid dispersion formation was confirmed by the presence of specific drug-polymer interactions and a single glass transition (T(g)) event.

Effect of temperature and moisture on the miscibility of amorphous dispersions of felodipine and poly(vinyl pyrrolidone).

The physical stability of amorphous molecular level solid dispersions will be influenced by the miscibility of the components. The goal of this work was to understand the effects of temperature and relative humidity on the miscibility of a model amorphous solid dispersion. Infrared spectroscopy was used to evaluate drug-polymer hydrogen bonding interactions in amorphous solid dispersions of felodipine and poly(vinyl pyrrolidone) (PVP).

Recrystallization of nifedipine and felodipine from amorphous molecular level solid dispersions containing poly(vinylpyrrolidone) and sorbed water.

Purpose: To compare the physical stability of amorphous molecular level solid dispersions of nifedipine and felodipine, in the presence of poly(vinylpyrrolidone) (PVP) and small amounts of moisture.

Methods: Thin amorphous films of nifedipine and felodipine and amorphous molecular level solid dispersions with PVP were stored at various relative humidities (RH) and the nucleation rate was measured. The amount of water sorbed at each RH was measured using isothermal vapor sorption and glass transition temperatures (Tg) were determined using differential scanning calorimetry.