When preparing siRNA-encapsulated solid lipid nanoparticles (siRNA-SLNs), cationic lipids are commonly included to condense and lipophilize the siRNA and thus increase its encapsulation in the SLNs. Unfortunately, cationic lipids also contribute significantly to the cytotoxicity and proinflammatory activity of the SLNs. Previously, our group developed a TNF-α siRNA-SLN formulation that showed strong activity against rheumatoid arthritis unresponsive to methotrexate in a mouse model.
View Article and Find Full Text PDFClofazimine (CFZ) is an important component of the World Health Organization's (WHO) recommended all-oral drug regimen for treatment of multi-drug resistant tuberculosis (MDR-TB). However, the lack of a dividable oral dosage form has limited the use of the drug in pediatric populations, who may require lowering of the dose to reduce the likelihood of adverse drug events. In this study, pediatric-friendly CFZ mini-tablets were prepared from micronized powder via direct compression.
View Article and Find Full Text PDFNiclosamide is an FDA-approved anthelmintic that is being studied in clinical trials as a chemotherapeutic and broad-spectrum antiviral. Additionally, several other applications are currently in the preclinical stage. Unfortunately, niclosamide is a poorly water soluble molecule, with reduced oral bioavailability, which hinders its use for new indications.
View Article and Find Full Text PDFThe feasibility of twin-screw corotating extruder as a continuous process mixer to prepare dry powder inhalation (DPI) powders was investigated. Interactive mixtures of 1% micronized budesonide, 0.3% magnesium stearate and 98.
View Article and Find Full Text PDFAntimicrob Agents Chemother
September 2022
Tuberculosis (TB) remains a major cause of morbidity and mortality, particularly in low- and middle-income countries where access to health care workers, cold-chain storage, and sterile water sources may be limited. Inhaled drug delivery is a promising alternative to systemic delivery of antimycobacterial drugs, as it enables rapid achievement of high infection-site drug concentrations. The off-patent drug clofazimine (CFZ) may be particularly suitable for this route, given its known systemic toxicities.
View Article and Find Full Text PDFRemdesivir dry powder for inhalation was previously developed using thin film freezing (TFF). A single-dose 24-h pharmacokinetic study in hamsters demonstrated that pulmonary delivery of TFF remdesivir can achieve plasma remdesivir and GS-441524 levels higher than the reported ECs of both remdesivir and GS-441524 (in human epithelial cells) over 20 h. The half-life of GS-4412524 following dry powder insufflation was about 7 h, suggesting the dosing regimen would be twice-daily administration.
View Article and Find Full Text PDFIn this work, we have developed and tested a dry powder form of niclosamide made by thin-film freezing (TFF) and administered it by inhalation to rats and hamsters to gather data about its toxicology and pharmacokinetics. Niclosamide, a poorly water-soluble drug, is an interesting drug candidate because it was approved over 60 years ago for use as an anthelmintic medication, but recent studies demonstrated its potential as a broad-spectrum antiviral with pharmacological effect against SARS-CoV-2 infection. TFF was used to develop a niclosamide inhalation powder composition that exhibited acceptable aerosol performance with a fine particle fraction (FPF) of 86.
View Article and Find Full Text PDFAAPS PharmSciTech
January 2021
The present study was designed to test the hypothesis that programmed cell death-1 (PD-1) siRNA can downregulate PD-1 expression in macrophages in culture and in tumor tissues in mice and inhibit tumor growth in a mouse model. PD-1 siRNA was encapsulated in solid lipid nanoparticles (SLNs), and the physical properties of the resultant SLNs were characterized. The ability of the PD-1 siRNA-SLNs to downregulate PD-1 expression was confirmed in J774A.
View Article and Find Full Text PDFUsing a model formulation of 80% gabapentin and 20% hydroxypropyl cellulose (Klucel), we investigate how differences in the geometry of mixing elements in the Leistritz Nano-16 and Micro-18 extruders affect granulation mechanisms and the properties of the resulting granules. Two extruders, Leistritz Nano-16 and Micro-18, commonly used in development and manufacturing, respectively, were used. The kneading blocks of the Nano-16 extruder are less efficient in dispersive mixing than the kneading blocks of the Micro-18 due to the thinner discs (2.
View Article and Find Full Text PDFRemdesivir exhibits in vitro activity against SARS-CoV-2 and was granted approval for emergency use. To maximize delivery to the lungs, we formulated remdesivir as a dry powder for inhalation using thin film freezing (TFF). TFF produces brittle matrix nanostructured aggregates that are sheared into respirable low-density microparticles upon aerosolization from a passive dry powder inhaler.
View Article and Find Full Text PDFWe investigated the feasibility of preparing high-potency tacrolimus dry powder for inhalation using thin film freezing (TFF). We found that using ultra-rapid freezing can increase drug loading up to 95% while maintaining good aerosol performance. Drug loading affected the specific surface area and moisture sorption of TFF formulations, but it did not affect the chemical stability, physical stability, and dissolution of tacrolimus.
View Article and Find Full Text PDFThe caveolin scaffolding domain peptide (CSP) is being developed for the therapeutic intervention of a lethal lung disease, idiopathic pulmonary fibrosis. While direct respiratory delivery of CSP7 (a 7-mer fragment of CSP) is considered an effective route, proper formulation and processing of the peptide are required. First, air-jet milling technology was performed in order to micronize the neat peptide powder.
View Article and Find Full Text PDFCounterions commonly remain with peptides in salt form after peptide purification. In animal and human studies, acetate counterions are a safer and more acceptable choice for peptides than others (e.g.
View Article and Find Full Text PDFThere is evidence that encapsulating glucocorticoids into nucleic acid-containing nanoparticles reduces the inflammatory toxicities of the nanoparticles. Herein, using betamethasone acetate (BA), a glucocorticoid, and a solid lipid nanoparticle formulation of siRNA, we confirmed that coencapsulating BA into the siRNA solid lipid nanoparticles significantly reduced the proinflammatory activity of the siRNA nanoparticles in a mouse model. Using TNF-α siRNA, we then showed that the BA and TNF-α siRNA coencapsulated into the solid lipid nanoparticles acted as a dual anti-inflammatory and synergistically reduced TNF-α release by mouse macrophages in culture following stimulation with lipopolysaccharide, as compared to solid lipid nanoparticles encapsulated with TNF-α siRNA or BA alone.
View Article and Find Full Text PDFThe influences of aqueous polymeric subcoats and pellet composition on the release properties of a highly water-soluble drug, chlorpheniramine maleate (CPM), from enteric coated pellets were investigated. Three different aqueous polymeric subcoats, Eudragit RD 100, Eudragit RS 30D, and Opadry AMB, were applied to 10% w/w CPM-loaded pellets that were then enteric coated with Eudragit L 30D-55. Observed drug release from the coated pellets in acidic media correlated with water vapor transmission rates derived for the subcoat films.
View Article and Find Full Text PDFThe thermal stability of polyethylene oxide (PEO) in sustained release tablets prepared by hot-melt extrusion was investigated. The weight average molecular weight of the polymer was studied using gel permeation chromatography. The chemical stability of PEO was found to be dependent on both the storage and processing temperature, and the molecular weight of the polymer.
View Article and Find Full Text PDFControlled-release theophylline containing spherical pellets were successfully produced by a hot-melt extrusion (HME) and spheronization process. A powder blend of anhydrous theophylline, Eudragit Preparation 4135 F, microcrystalline cellulose and polyethylene glycol 8000 powder was sieved, blended and then melt-extruded in a Randcastle Microtruder. The hot-melt extruded pellets were prepared by first cutting a thin, extruded composite rod into symmetrical pellets.
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