Journal of pharmaceutical sciences最新文献

Lemborexant is a dual orexin receptor antagonist assigned to class II of the Biopharmaceutics Classification System (BCS). Thus, the ICH M9 Guideline excludes immediate-release (IR) solid oral dosage forms containing lemborexant from BCS-based biowaivers, irrespective of their in vitro dissolution behavior. By contrast, classification of lemborexant according to the refined Developability Classification System (rDCS) falls into class I, indicating few biopharmaceutics risks. Customized rDCS investigations identify dissolution as the main risk factor, in line with clinical data in humans which suggest that the absorption of lemborexant is limited neither by solubility nor by permeability. Instead, any risks lie in dissolution. Analysis by the rDCS coupled with biorelevant dissolution testing thus provides a way forward for manufacturers to mitigate the risks associated with changes in formulation or introduction of a generic version prior to running clinical bioequivalence (BE) studies. As a way forward regarding biowaivers for lemborexant and similar cases, where justifying BE based on the current BCS-based approach is not possible, a four-step pathway towards establishing BE virtually could be adopted as follows: (i) rDCS analysis to identify critical bioavailability attributes, (ii) comparative (biorelevant) dissolution testing, (iii) Physiologically Based Biopharmaceutics Modeling (PBBM), and (iv) virtual BE assessment.

Genome editing technology using the CRISPR-Cas system is attracting much attention not only as a promising experimental tool for analysis of genome functions, but also as a novel therapeutic approach for genetic disorders. Among the various types of Cas proteins, Cas12a is expected to be a promising gene editing tool due to its unique properties, including low off-target effects. As Cas proteins are of prokaryotic origin, they need to be fused with appropriate localization signals to perform their function in eukaryotic cells. Cas12a proteins fused with a nuclear localization signal (NLS) have been developed so far, but the relation between the nuclear localization activity and the genome editing efficiency has not been fully elucidated. Here, utilizing two Cas12a orthologs, AsCas12a and LbCas12a, with various number of NLSs derived from various origins, we revealed that the improved nuclear localization resulted in increased genome editing efficiencies when expressed using adenovirus (Ad) vector in cultured cells. However, when they were expressed in mouse liver, the improvement of the nuclear localization activity was not necessarily required to achieve the maximum genome editing efficiency four weeks after Ad vector administration. These data indicated that the optimized NLS modification of Cas12a proteins in in vitro situations differed from that in in vivo.

There is growing interest in the oral delivery of poorly permeable peptide drugs; however, the effect of biorelevant colloids found in the aqueous gastrointestinal environment on peptide drug solution behavior has been largely understudied. In this work, we detail the molecular level interactions between octreotide, a water-soluble macrocyclic peptide drug, and biorelevant colloids, i.e. bile salt micelles and bile salt-phospholipid mixed micelles, via dialysis membrane flux experiments and proton nuclear magnetic resonance (¹H NMR) spectroscopy. A modified alanine scan was employed to generate eight mutated octreotide analogs; the impact of individual amino acid mutations on peptide dialysis membrane flux rates in micellar (trihydroxy and dihydroxy) bile salt solutions as well as fasted state simulated intestinal fluid (FaSSIF) and fed state simulated intestinal fluid (FeSSIF) was evaluated and compared against the parent peptide, octreotide. We show that octreotide interacts more strongly with dihydroxy bile salt micelles than trihydroxy bile salt micelles in solution, and in FaSSIF/FeSSIF media, octreotide mainly interacts with the phospholipid component. These interactions are largely mediated by hydrophobic interactions of octreotide's aromatic residues as well as electrostatic interactions between octreotide's basic Lys residue and terminal amine.

Amorphous solid dispersions (ASDs) are widely employed as a strategy to improve oral bioavailability of poorly water soluble compounds. Typically, optimal dissolution performance from a polyvinylpyrrolidone vinyl acetate (PVPVA) based ASD is observed at relatively low drug loading limit. Above a certain drug load, termed limit of congruency (LoC), the release from ASDs significantly decreases. So far, the majority of the dissolution behavior has been tested in conditions where the drug primarily exists in unionized form. In this work, the impact of pH of the dissolution environment on the release performance of ASDs of an ionizable drug was studied. Atazanavir (ATZ), a weakly basic drug with a pK_a of 4.5 was used as a model compound and PVPVA was used as a non-ionizable matrix polymer. Dissolution rate was measured using Wood's apparatus which normalizes the surface area of the dissolving tablet. The pH of the dissolution media was varied between 1 and 6.8, cover a range where ATZ exists as >99% ionized or unionized species. At pH 6.8, near complete release was observed only when the drug load was ≤ 6%. Unlike typically observed drastic decline in release behavior for PVPVA based ASDs above LoC, ATZ ASDs underwent gradual decline in dissolution behavior when the DL was increased to 8%. This was attributed to potential formation of an ATZ-PVPVA associated phase with dissolution rate slower than neat PVPVA. However, the 10% DL ASD showed negligible ATZ release. On another extreme (pH 1) where ATZ is ∼100% ionized, the dissolution rate of ATZ was faster than that of PVPVA. ASD dissolution rate was found to be slower than that of the neat drug but faster than PVPVA and interestingly, did not change with DL. This can be attributed to formation of an ionized ATZ-PVPVA phase which controls the dissolution rate of the ASD. At pH 3, where the drug is ∼97% ionized, near complete release was observed for drug loads ≤ 8%. To observe significant increase in drug loading with near complete release, >98% ionization of ATZ was required. At pH 2 where ATZ is ∼99.7% ionized, near complete release was observed for drug loads up to 30%. Furthermore, the deterioration in dissolution performance with an increase in drug load continued to be gradual at pH 2. The enhancement in dissolution performance did not correlate with solubility enhancement of ATZ due to ionization. We theorize that the enhancement in the dissolution performance due to ionization is the result of formation of an ionized ATZ-PVPVA phase which increases the hydrophilicity and the miscibility of the ASD. This can help resist water induced phase separation during ASD dissolution and therefore, result in continuous, and congruent dissolution of the drug and polymer.

A microscopic erosion time test was recently described to anticipate amorphous solid dispersion (ASD) drug load dispersibility limit, using 0.5ml media volume. Studies here build upon this microscope-enabled method but focus on drug and polymer dissolution from an ASD disc, along with imaging. The objective was 1) to design and build a microscope-enabled disc dissolution system (MeDDiS) with a 900mL dissolution volume and 2) assess the ability of MeDDiS imaging of dissolving discs to provide concordance with measured drug and polymer dissolution profiles. MeDDiS employed a digital microscope to image ASD discs and a one-liter vessel for dissolution. ASD discs containing ritonavir (5-50% drug load) and PVPVA were fabricated and subjected to in vitro dissolution using MeDDiS, where disc diameter was quantified with time. Ritonavir and PVPVA release were also measured. Results indicate concordance between imaging and dissolution. Both found 25% drug load to provide high drug and polymer release, but 30% yielded low release. Quantitatively, MeDDiS images predicted drug and polymer release profile, both above and below the drug load cliff. Overall, studies here describe a MeDDiS which has promised to anticipate drug and polymer dissolution, via imaging of dissolving discs, above and below the ASD drug load cliff.

Employing small extracellular vesicles (EVs) as drug delivery vehicles presents a plethora of advantages over conventional drug delivery methods, including biological compatibility, engineering versatility for targeted delivery, and biodegradability. Therefore, strategies aimed at amplifying their therapeutic potential involve developing efficient, tissue-specific, and non-immunogenic delivery approaches. Despite rapid advancements in the realm of EVs as drug delivery systems in recent years, the availability of a high-yield, reproducible, and cost-effective source for EVs production and isolation remains a limiting factor for practical application. In this study, we isolated EVs from Saccharomyces cerevisiae (S.c) and loaded them with cargoes such as hsa-miR-143 (an apoptosis-inducing miRNA) or miR-H6 (a miRNA targeting HSV-1). We demonstrated the capability of these EVs to deliver microRNAs or even large mRNA to a variety of cell types. The therapeutic potential of S.c-derived EVs (S.c-EVs) was further evidenced by their ability to inhibit tumor growth in animal models. The S.c-EVs proved to be safe and non-immunogenic in vivo. Our results suggest that Saccharomyces cerevisiae represents a cost-effective source of extracellular vesicles, serving as nanocarriers for functional drug delivery in therapeutic applications.

Use of solubilization carriers for poorly soluble drugs may disturb transmembrane absorption by lowering the activity of drug molecules, which is known as the solubility-permeability interplay. However, although many in vitro studies have indicated the negative impacts of use of solubilization carriers for oral absorption, in vivo studies that showed the interplay effect are limited. This study provides systematic in vitro, in situ, and in vivo investigation of the interplay effect of cyclodextrin using dexamethasone as a model drug. The evaluation methods included permeation through polymeric, artificial lipid, cell, and intestinal closed-loop membranes. Then, the results were compared with oral administration studies in mice and dogs. Although the interplay effect was clearly observed in the in vitro studies, no obvious interplay was found in the in vivo studies, suggesting that the interplay effect is more prominent in the in vitro permeation studies. Absence of in vivo interplay was attributed to the dilution effect in the gastrointestinal tract, interaction of the drug with living components, and clearance of the drug after membrane permeation. Overall, this investigation clearly demonstrated the applicability and limitations of in vitro permeation studies for predicting the interplay effects of solubilizers after the oral administration.

A 45% drug loaded (DL) amorphous nanoparticle (ANP) formulation for a BCS IV drug demonstrated promising pharmacokinetics in dogs (Purohit, et al, J. Pharm. Sci. 2023(113)1007-1019). This preclinical data enabled a human proof-of-concept assessment opportunity. The ANP freeze dried powder for oral suspension was prepared using solvent/antisolvent precipitation followed by organic solvent removal and freeze drying (FD). Challenges manifested during scale-up from 50g to 280g. Given the preclinical data, formulation change was restricted, therefore, process modifications were implemented. Cold collection after precipitation prevented particle growth but resulted in 75 nm particles at clinical scale (CS), compared to 150 nm at laboratory scale (LS). This size decrease rendered stabilizer amounts suboptimal for FD operation. Consequently, when FD powder was resuspended in water a smaller fraction of particles was below 450 nm (by filtration), ∼65% for CS compared to ∼85% for LS. Formulation was stable for > 6 months, evaluated by monitoring moisture content, assay, powder X-ray diffraction (PXRD), and redispersion time. Despite ∼65% re-dispersibility, this 45% DL formulation in humans had higher C_max and AUC ∼73% and ∼46% respectively in fasted-state, and under fed-state it met bioequivalence criteria for AUC but C_max was 20% lower compared to reference (10% DL ASD tablets) demonstrating advantage of ANP strategy over ASD approach.

Thermodynamic properties, including solubility and miscibility, which are highly correlated with amorphous solid dispersion physical stability were identified for the complex solid forms of bromopropamide using simultaneous X-ray diffraction (XRD)-differential scanning calorimetry (DSC). The most stable solid form of bromopropamide was crystallized and its crystal structure was solved. The crystallized material was characterized using simultaneous XRD-DSC measurements, which allowed dual analyses of a single sample. Transitions of bromopropamide during heating resulted in observation of the unique diffraction patterns of its different solid forms. The dissolution endpoint (T_end) was measured for various mixtures of bromopropamide and polyvinylpyrrolidone-vinyl acetate random copolymer (PVPVA). The use of XRD-DSC allowed confident and accurate measurements of the T_end for a large range of compositions, assisting in the estimation of drug-polymer solubility and miscibility. Thermodynamic properties identified using combined XRD-DSC were further compared to those obtained using only DSC data. It was found that DSC data in isolation can lead to ambiguity, misinterpretations, and incorrect conclusions, especially for a solid demonstrating multiple, closely related forms.

This special edition of the Journal of Pharmaceutical Sciences is dedicated to Professor Lynne S. Taylor (Retter Distinguished Professor of Pharmacy, Department of Industrial and Molecular Pharmaceutics, Purdue University), to honor her distinguished career as a pharmaceutical scientist and educator. The goal of this commentary is to provide an overview of Professor Taylor's career path, summarize her key research contributions, and provide some insight into her personal and professional contributions as an educator, mentor, wife, mother, friend, and adventurer.