Solubility modulation of bicalutamide using porous silica

Data-Driven Modeling of the Bicalutamide Dissolution from Powder Systems

Low solubility of active pharmaceutical compounds (APIs) remains an important challenge in dosage form development process. In the manuscript, empirical models were developed and analyzed in order to predict dissolution of bicalutamide (BCL) from solid dispersion with various carriers. BCL was chosen as an example of a poor water-soluble API. Two separate datasets were created: one from literature data and another based on in-house experimental data. Computational experiments were conducted using artificial intelligence tools based on machine learning (AI/ML) with a plethora of techniques including artificial neural networks, decision trees, rule-based systems, and evolutionary computations. The latter resulting in classical mathematical equations provided models characterized by the lowest prediction error. In-house data turned out to be more homogeneous, as well as formulations were more extensively characterized than literature-based data. Thus, in-house data resulted in better models than literature-based data set. Among the other covariates, the best model uses for prediction of BCL dissolution profile the transmittance from IR spectrum at 1260 cm^-1 wavenumber. Ab initio modeling-based in silico simulations were conducted to reveal potential BCL-excipients interaction. All crucial variables were selected automatically by AI/ML tools and resulted in reasonably simple and yet predictive models suitable for application in Quality by Design (QbD) approaches. Presented data-driven model development using AI/ML could be useful in various problems in the field of pharmaceutical technology, resulting in both predictive and investigational tools revealing new knowledge.

Exploring the Potential of Mesoporous Silica as a Carrier for Puerarin: Characterization, Physical Stability, and In Vivo Pharmacokinetics

The aim of this study was to evaluate the use of a novel porous silica carrier, AEROPERL^® 300 Pharma (AP), to improve the in vitro release and oral bioavailability of puerarin (PUE) in solid dispersions (SDs). PUE-AP SD formulations with different ratios of drug to silica (RDS) were prepared by the solvent method. The scanning electron microscopy (SEM) results indicated that the dispersion of PUE improved as the concentration of AP was increased. The differential scanning calorimetry (DSC) and X-ray diffraction (XRD) results revealed that PUE mostly existed in an amorphous state in the SDs. The rate of drug dissolution from the SDs was significantly higher than that from the PUE powder (p < 0.05). The in vitro drug release percentage from the PUE-AP SDs increased as the RDS was reduced. The oral bioavailability of PUE from the SDs improved when using AP, as indicated by AUC_(0-∞), which was 2.05 and 2.01 times greater than that of the PUE (API) and PVP K30 SDs, respectively (p < 0.05). The drug content, in vitro release profiles, and the amorphous state of PUE in the PUE-AP SDs showed no significant changes after being stored at room temperature for 6 months or under accelerated conditions (40 ± 2°C, 75 ± 5% relative humidity) for 3 months. AP has a high pore volume, large specific surface area, excellent flowability, and hydrophilic properties, making it capable of improving the dissolution and bioavailability of poorly water-soluble drugs.

Study the influence of formulation process parameters on solubility and dissolution enhancement of efavirenz solid solutions prepared by hot-melt extrusion: a QbD methodology

The current study investigates the dissolution rate performance of amorphous solid solutions of a poorly water-soluble drug, efavirenz (EFV), in amorphous Soluplus® (SOL) and Kollidon® VA 64 (KVA64) polymeric systems. For the purpose of the study, various formulations with varying drug loadings of 30, 50, and 70% w/w were developed via hot-melt extrusion processing and adopting a Box-Behnken design of experiment (DoE) approach. The polymers were selected based on the Hansen solubility parameter calculation and the prediction of the possible drug-polymer miscibility. In DoE experiments, a Box-Behnken factorial design was conducted to evaluate the effect of independent variables such as Soluplus® ratio (A₁), HME screw speed (A₂), and processing temperature (A₃), and Kollidon®VA64 ratio (B₁), screw speed (B₂), and processing temperature (B₃) on responses such as solubility (X₁ and Y₁) and dissolution rate (X₂ and Y₂) for both ASS [EFV:SOL] and BSS [EFV:KVA64] systems. DSC and XRD data confirmed that bulk crystalline EFV transformed to amorphous form during the HME processing. Advanced chemical analyses conducted via 2D COSY NMR, FTIR chemical imaging, AFM analysis, and FTIR showed that EFV was homogenously dispersed in the respective polymer matrices. The maximum solubility and dissolution rate was observed in formulations containing 30% EFV with both SOL and KVA64 alone. This could be attributed to the maximum drug-polymer miscibility in the optimized formulations. The actual and predicted values of both responses were found precise and close to each other.

Lipophilicity and hydrophobicity considerations in bio-enabling oral formulations approaches – a PEARRL review

Objectives

This review highlights aspects of drug hydrophobicity and lipophilicity as determinants of different oral formulation approaches with specific focus on enabling formulation technologies. An overview is provided on appropriate formulation selection by focussing on the physicochemical properties of the drug.

Key findings

Crystal lattice energy and the octanol–water partitioning behaviour of a poorly soluble drug are conventionally viewed as characteristics of hydrophobicity and lipophilicity, which matter particularly for any dissolution process during manufacturing and regarding drug release in the gastrointestinal tract. Different oral formulation strategies are discussed in the present review, including lipid-based delivery, amorphous solid dispersions, mesoporous silica, nanosuspensions and cyclodextrin formulations.

Summary

Current literature suggests that selection of formulation approaches in pharmaceutics is still highly dependent on the availability of technological expertise in a company or research group. Encouraging is that, recent advancements point to more structured and scientifically based development approaches. More research is still needed to better link physicochemical drug properties to pharmaceutical formulation design.

Preparation and tableting of long-term stable amorphous rutin using porous silica

Amorphous state of drugs increases the oral bioavailability, but typically faces physical stability problems. Amorphous rutin was generated and physically stabilized by encapsulating inside mesopores of porous AEROPERL® 300 Pharma and named as rutin CapsMorph® in this study. AEROPERL® 300 Pharma was loaded with rutin dissolved in DMSO containing Tween 80, and subsequently the solvent evaporated (wetness impregnation method). The loading process was monitored by light microscopy and scanning electron microscopy (SEM). X-ray diffraction (XRD) and differential scanning calorimetry (DSC) were used to confirm the amorphous state in AEROPERL® 300 Pharma. A loading of 20% of the rutin-AEROPERL® 300 Pharma mixture was obtained. The amorphous state proved to be stable over 2years of storage at room temperature. Due to the amorphous state and the nanosize of the rutin in the mesopores, the kinetic saturation solubility increased to about 4mg/ml (water, 0.1MHCl, pH 6.8PBS) compared to the maximum observed thermodynamic equilibrium solubility of rutin raw drug powder of only 74.48±1.42μg/ml in pH 6.8PBS (=increase by factor about 54). The dissolution velocity also increased distinctly, e.g. about 96.1% of rutin dissolution from CapsMorph® powder in water within 5min compared to less than 40% of raw drug powder after 3h. Tablets were produced with rutin CapsMorph®, raw drug powder and their dissolution velocity compared to a marketed product. About 83.0-95.6% were released from the rutin CapsMorph® tablet within 5min, compared to 42.7-52.5% from the marketed tablet after 3h (water, 0.1MHCl, pH 6.8PBS). After dissolution the supersaturation level of rutin CapsMorph® remained over about 2h, then solubility slowly reduced, but remained after 48h still multifold above the thermodynamic rutin solubility. This should be sufficient for many poorly soluble drugs to achieve a sufficient bioavailability. For optimal exploitation of the supersaturation, a multiple step release system could be used, e.g. release of CapsMorph® particles every 2-3h.

Solubility and dissolution enhancement of efavirenz hot melt extruded amorphous solid dispersions using combination of polymeric blends: A QbD approach

Efavirenz is a non-nucleoside reverse transcriptase inhibitor and categorized in to BCS class II drug. The aim of the present investigation was to apply quality by design approach to enhance the solubility, dissolution and stability of amorphous solid dispersions (ASDs) of efavirenz using a combination of Soluplus® and HPMCAS-HF polymers. In design of experiments, the user defined quadratic model was used to study the effect of variable concentrations of Soluplus® and HPMCAS-HF for the formation of ASDs of efavirenz. Similarly, a prototype ASD was made using Soluplus® as a carrier with efavirenz loading of 30%. The efavirenz ASDs granular extrudates were evaluated for saturation solubility as well as dissolution rate studies. X-ray powder diffraction, Differential scanning calorimetry, Fourier transform infrared, Atomic force microscopy and FTIR imaging to determine the solid state of efavirenz in the ASDs. DSC and XRD data confirmed that bulk crystalline efavirenz transformed to the amorphous form during the hot melt extrusion processing. Prototype ASD batch showed instability upon storage as per ICH guidelines over a period of 6months, observations inferred from DSC, XRD and in vitro dissolution studies. The maximum dissolution rate was observed when Soluplus® and HPMCAS-HF was in ratio of (60:20) as optimized by design of experiments study. Moreover, the optimized ASDs batch were stable at 40°C, 75% RH for a period of 6months without any dissolution rate changes, and remained into amorphous state.