Biology subjects

Warnken, Z. N.

Publications and source records attributed to Warnken, Z. N..

4 recordsLinked to original sources

bioRxiv2022

Feasibility of intranasal delivery of thin-film freeze-dried, mucoadhesive AS01B-adjuvanted vaccine powders

Intranasal vaccination by directly applying a vaccine dry powder is appealing. However, a method that can be used to transform a vaccine from a liquid to a dry powder and a device that can be used to administer the powder to the desired region(s) of the nasal cavity are critical for a successful intranasal vaccination. In the present study, using a model vaccine that contains the liposomal AS01B as an adjuvant and ovalbumin (OVA) as a model antigen, it was shown that thin-film freeze-drying can be applied to convert the liquid vaccine containing sucrose at a sucrose to lipid ratio of 15:1 (w/w), in the presence or absence of carboxymethyl cellulose sodium salt (CMC) as a mucoadhesive agent, into dry powders. Ultimately, the thin-film freeze-dried AS01B/OVA vaccine powder containing 1.9% w/w of CMC (i.e., TFF AS01B/OVA/CMC1.9% powder) was selected for additional evaluation because the TFF AS01B/OVA/CMC1.9% powder was mucoadhesive and maintained the integrity of the antigen and the physical properties of the vaccine. Compared to the TFF AS01B/OVA powder that did not contain CMC, the TFF AS01B/OVA/CMC1.9% powder had a lower moisture content and a higher glass transition temperature and was more porous. In addition, the TFF AS01B/OVA/CMC1.9% thin films were relatively thicker than the TFF AS01B/OVA thin films without CMC. When sprayed with the Unit Dose System Powder (UDSP) nasal device, the TFF AS01B/OVA powder and the TFF AS01B/OVA/CMC1.9% powder generated similar particle size distribution curves, spray patterns, and plume geometries. Importantly, after the TFF AS01B/OVA/CMC1.9% powder was sprayed with the UDSP nasal device, the integrity of the OVA antigen and the AS01B liposomal adjuvant did not change. Finally, a Taguchi L8 orthogonal array was applied to identify the optimal parameters for using the UDSP device to deliver the TFF AS01B/OVA/CMC1.9% vaccine powder to the middle and lower turbinate and the nasopharynx regions in both adult and child nasal casts. Results from this study showed that it is feasible to apply the TFF technology to transform a nasal vaccine candidate from liquid to a dry powder and then use the UDSP nasal device to deliver the TFF vaccine powder to the desired regions in the nasal cavity for intranasal vaccination.

pharmacology and toxicology↗

bioRxiv2021

Niclosamide Inhalation Powder Made by Thin-Film Freezing: Pharmacokinetic and Toxicology Studies in Rats and Hamsters

In this work, we have developed and tested in vivo a dry powder form of niclosamide made by thin-film freezing (TFF) and administered it by inhalation to rats and hamsters. The niclosamide dry powder, suitable for inhalation, is being developed as a therapeutic agent against COVID-19 infection. 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 a specific pharmacological effect against SARS-CoV-2 infection. In the past, clinical trials for other indications were terminated prior to completion due to low and highly variable oral bioavailability. In order to quickly address the current pandemic, targeting niclosamide directly to the lungs is rational to address the COVID-19 main clinical complications. Thin-film freezing technology was used to develop a niclosamide inhalation powder composition that exhibited acceptable aerosol performance with a fine particle fraction (FPF) of 86.0% and a mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD) of 1.11 m and 2.84, respectively. This formulation not only proved to be safe after an acute three-day, multi-dose pharmacokinetic study in rats as evidenced by histopathology analysis, but also was able to achieve lung concentrations above the required IC50 and IC90 levels for at least 24 h after a single administration in a Syrian hamster model. To conclude, we successfully developed a niclosamide dry powder inhalation formulation by thin-film freezing for further scale-up and clinical testing against the COVID-19 infection. This approach overcomes niclosamides limitation of poor oral bioavailability by targeting the drug directly to the primary site of infection, the lungs.

pharmacology and toxicology↗

bioRxiv2020

In Vivo Pharmacokinetic Study of Remdesivir Dry Powder for Inhalation in Hamsters

Remdesivir dry powder for inhalation was previously developed using thin film freezing (TFF). A single-dose 24-hour pharmacokinetic study in hamsters, a small animal model for SARS-CoV-2, demonstrated that pulmonary delivery of TFF remdesivir can achieve plasma remdesivir and GS-441524 levels higher than the reported EC50s of both remdesivir and GS-441524 (in human epithelial cells) over 20 hours. The half-life of GS-4412524 following dry powder insufflation was about 7 hours, suggesting the dosing regimen would be twice daily administration. Although the remdesivir-Captisol(R) (80/20 w/w) formulation showed faster and greater absorption of remdesivir and GS-4412524 in the lung, remdesivir-leucine (80/20 w/w) exhibited a greater Cmax with shorter Tmax and lower AUC of GS-441524, indicating lower total drug exposure is required to achieve a high effective concentration against SAR-CoV-2. In conclusion, remdesivir dry powder for inhalation would be a promising alternative dosage form for the treatment of COVID-19 disease.

pharmacology and toxicology↗

bioRxiv2020

Amorphous solid dispersions and the confounding effect of nanoparticles in in vitro dissolution and in vivo testing: Niclosamide as a case of study

We developed an amorphous solid dispersion (ASD) of the poorly water-soluble molecule niclosamide that achieved more than a 2-fold increase in bioavailability. Notably, this niclosamide ASD formulation increased the apparent drug solubility about 60-fold relative to the crystalline material due to the generation of nanoparticles. Niclosamide is a weakly acidic drug, BCS class II, and a poor glass former with low bioavailability in vivo. Hot-melt extrusion is a high-throughput manufacturing method commonly used in the development of ASDs for increasing the apparent solubility and bioavailability of poorly water-soluble compounds. We utilized the polymer polyvinylpyrrolidone-vinyl acetate (PVP-VA) to manufacture niclosamide ASDs by extrusion. Samples were analyzed based on their microscopic and macroscopic behavior and their intermolecular interactions, using DSC, XRD, NMR, FTIR, and DLS. The niclosamide ASD generated nanoparticles with a mean particle size of about 100 nm in FaSSIF media. In a side-by-side diffusion test, these nanoparticles produced a 4-fold increase in niclosamide diffusion. We successfully manufactured amorphous extrudates of the poor glass former niclosamide that showed remarkable in vitro dissolution and diffusion performance. These in vitro tests were translated to a rat model that also showed an increase in oral bioavailability. O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

pharmacology and toxicology↗