BACKGROUND: Patients with cystic fibrosis commonly suffer from lung infections caused by Pseudomonas aeruginosa. Recently, the Levofloxacin (LVF) nebulizing solution (Quinsair®) has been prescribed for the antimicrobial management. The sustained-release (SR) dry powder formulation of LVF is a convenient alternative to Quinsair®. It has the potential to enhance patient convenience and decrease the likelihood of drug resistance over time.
OBJECTIVE: In this paper, we set forth to formulate and evaluate the potential application of sodium alginate (SA) and sodium carboxymethylcellulose (SCMC) for sustained pulmonary delivery of LVF.
METHODS: The spray-dried (SD) LVF microparticles were formulated using SCMC and SA along with L-leucine (Leu). The microparticles were analyzed in terms of particle size, morphology, x-ray diffraction (XRD), in-vitro drug release, and aerodynamic properties. Selected formulations were further proceeded to short-term stability test.
RESULTS: The polymer-containing samples displayed process yield of 33.31%-39.67%, mean entrapment efficiency of 89% and volume size within the range of 2-5 μm. All the hydrogel microparticles were amorphous and exhibited rounded morphology with surface indentations. Formulations with a drug-to-excipient ratio of 50:50 and higher, showed a 24-h SR. The aerodynamic parameters were fine particle fraction and emitted dose percentage ranging between 46.21%-60.6% and 66.67%-87.75%, respectively. The short-term stability test revealed that the formulation with a 50:50 drug-to-excipient ratio, containing SA, demonstrated better physical stability.
CONCLUSIONS: The selected formulation containing SA has the potential to extend the release duration. However, further enhancements are required to optimize its performance.

Particulate contamination, the unintentional presence of particles in parenteral fluids, is associated with potential risks such as phlebitis and thrombophlebitis. Recent guidelines recommend the use of filter needles when withdrawing parenteral fluid from vials with a rubber stopper. However, the literature is limited and lacks clarity regarding the advantages of filter needles over conventional needles. The aim of this study was to assess the compliance of parenteral fluids regarding particulate contamination after withdrawing fluid using both conventional needles and filter needles, following the guidelines of European Pharmacopoeia (Ph. Eur.) and United States Pharmacopoeia (USP). Visible particles were counted through visual inspection and sub-visible particles were quantified utilizing the light obscuration particle count test. Particle counts for both types of needles were compared to Ph. Eur. and USP standards and differences in particle contamination were assessed using a Mann-Whitney U test. Both types of needles demonstrated compliance with Ph. Eur. and USP standards regarding particulate contamination of visible and sub-visible particles. However, filter needles exhibited a significantly higher particle count for particles with a size of ≥25 µm compared to conventional needles (p = 0.0029). In conclusion, both types of needles demonstrate suitability for aspirating fluid from vials featuring rubber stoppers regarding particulate contamination. Nevertheless, non-filter needles are preferred for withdrawing fluid from vials with a rubber stopper over filter needles due to their lower cost.

Producing solid-state formulations of biologics remains a daunting task despite the prevalent use of lyophilization and spray drying technologies in the biopharmaceutical industry. The challenges include protein stability (temperature stresses), high capital costs, particle design/controllability, shortened processing times and manufacturing considerations (scalability, yield improvements, aseptic operation, etc.). Thus, scientists/engineers are constantly working to improve existing methodologies and exploring novel dehydration/powder-forming technologies. Microglassification™ is a dehydration technology that uses solvent extraction to rapidly dehydrate protein formulations at ambient temperatures, eliminating the temperature stress experienced by biologics in traditional lyophilization and spray drying methods. The process results in microparticles that are spherical, dense, and chemically stable. In this study, we compared the molecular stability of a monoclonal antibody formulation processed by lyophilization to the same formulation processed using Microglassification™. Both powders were placed on stability for 3 months at 40 °C and 6 months at 25 °C. Both dehydration methods showed similar chemical stability, including percent monomer, charge variants, and antigen binding. These results show that Microglassification™ is viable for the production of stable solid-state monoclonal antibody formulations.

Binder jetting (BJ) 3D printing is especially suitable for the fabrication of an orodispersible solid dosage form, as it is an efficient way to avoid the use of mechanical forces typical for compaction-based processes. However, one of the existing challenges related to pharmaceutical applications of BJ is the relatively high amount of binder needed in the primary powder to ensure the sufficient mechanical strength of printed products. In this study, a strategy based on pre-processing with a thin layer coating was explored. With this strategy, the matrix particles (lactose monohydrate) of the primary powder for BJ 3D printing were coated with the binder (polyvinylpyrrolidone, PVP). The investigated compositions of the primary powder contained PVP at three levels, namely, 10 %, 15% and 20% (w/w). The primary powder compositions were prepared with or without the coated lactose powder, and they were subsequently 3D BJ printed into oral solid products with paracetamol as a model active drug substance. The presence of coated lactose in the primary powder increased the interparticulate interactions in the BJ 3D printed products. Especially for the composition with a relatively small amount of binder (i.e., 10% and 15% w/w PVP in the primary powder), the use of coated particles significantly improved the resistance to crushing and decreased the disintegration time of printed products. In conclusion, thin layer coating is an effective way to pre-process primary powder particles for BJ 3D printing of oral solid products.

This study investigates how backgrounded membrane imaging (BMI) can be used in combination with convolutional neural networks (CNNs) in order to quantitatively and qualitatively study subvisible particles in both protein biopharmaceuticals and samples containing synthetic model particles. BMI requires low sample volumes and avoids many technical complications associated with imaging particles in solution, e.g., air bubble interference, low refractive index contrast between solution and particles of interest, etc. Hence, BMI is an attractive technique for characterizing particles at various stages of drug product development. However, to date, the morphological information encoded in brightfield BMI images has scarcely been utilized. Here we show that CNN based methods can be useful in extracting morphological information from (label-free) brightfield BMI particle images. Images of particles from biopharmaceutical products and from laboratory prepared samples were analyzed with two types of CNN based approaches: traditional supervised classifiers and a recently proposed fingerprinting analysis method. We demonstrate that the CNN based methods are able to efficiently leverage BMI data to distinguish between particles comprised of different proteins, various fatty acids (representing polysorbate degradation related particles), and protein surrogates (NIST ETFE reference material) only based on BMI images. The utility of using the fingerprinting method for comparing morphological differences and similarities of particles formed in distinct drug products and/or laboratory prepared samples is further demonstrated and discussed through three case studies.

Particles in biopharmaceutical formulations remain a hot topic in drug product development. With new product classes emerging it is crucial to discriminate particulate active pharmaceutical ingredients from particulate impurities. Technical improvements, new analytical developments and emerging tools (e.g., machine learning tools) increase the amount of information generated for particles. For a proper interpretation and judgment of the generated data a thorough understanding of the measurement principle, suitable application fields and potential limitations and pitfalls is required. Our review provides a comprehensive overview of novel particle analysis techniques emerging in the last decade for particulate impurities in therapeutic protein formulations (protein-related, excipient-related and primary packaging material-related), as well as particulate biopharmaceutical formulations (virus particles, virus-like particles, lipid nanoparticles and cell-based medicinal products). In addition, we review the literature on applications, describe specific analytical approaches and illustrate advantages and drawbacks of currently available techniques for particulate biopharmaceutical formulations.

Real time analysis of pharmaceuticals in controlled release nano and microsystems remains a challenge. It is hypothesized that fluorine 19 nuclear magnetic resonance (19F qNMR) can be used for real time quantification and in vitro release of maraviroc (MVC). The release of maraviroc was analyzed in simulated body fluids from spray dried sodium alginate microspheres (MS) using the 19F qNMR method. Calibration produced a linearity curve in concentration range (0.42 mg/ml - 15 mg/ml), and the limits of detection and quantification values were 0.97 mg/ml and 2.93 mg/ml, respectively. The method was confirmed to be specific, accurate, precise, and robust (%RSE > 2%). MVC was successfully microencapsulated (18% w/w) as evidenced by the FT-IR spectra and SEM images. The MS had an average diameter of 2.522 ± 0.15 μm, with a zeta potential of - 61.31 ± 2.1 mV. Overall, the 19F qNMR method enabled a direct and real time quantification of MVC for an efficient drug release kinetics. This approach could be potentially used to quantify fluorinated drug potency, purity, and stability, and evaluate in vitro release kinetic from different formulations.

Among patients that receive Remicade® therapy, more than 20% have adverse infusion related reactions and approximately 50% have immunogenic responses.1-3 Upon characterization of initial Remicade®-IV solution we observed a high concentration of subvisible particles that could inadvertently be delivered to patients. This solution was processed through the IV infusion system, mimicking the typical clinical administration setup - either with or without an in-line filter connected to the IV line. The samples generated thereafter were tested using various in vitro assays for activation of the innate immune system via cytokine release in whole blood and in peripheral blood mononuclear cell (PBMC) cultures, and activation of the Toll like receptors (TLRs). Activation of the adaptive immune system was evaluated by monitoring upregulation of surface receptors on dendritic cells (DCs) and CD4+ T cell proliferation in response to IV solution of Remicade®. Our results indicate that subvisible particles in Remicade®-saline solution have a significant role in activation of the immune system but there are extrinsic factors potentially contributed by the in-line filters or other process parameters that also contribute to immune system activation.

A novel polymeric material, poly(δ-valerolactone-co-allyl-δ-valerolactone) (PVL-co-PAVL), was used to manufacture microparticles (MPs) for sustained drug delivery. PVL-co-PAVL MPs were formulated using a modified oil-in-water approach, followed by a UV-initiated cross-linking process. Prepared MPs had a smooth spherical morphology and cross-linking of the copolymer was found to improve the integrity and thermal stability of the MPs. Paclitaxel (PTX) was successfully loaded into the MPs at a high drug loading capacity, using a post-loading swelling-equilibrium method. In vitro evaluation showed that the PVL-co-PAVL MPs provide sustained release of PTX, which exhibited first-order release kinetics. A subsequent pilot pharmacokinetic study was carried out on the PTX-loaded PVL-co-PAVL MPs. During this study, serum levels of PTX were monitored following subcutaneous administration of the MPs to Sprague-Dawley rats. Overall, the in vivo release of PTX from the MPs was lower than expected based on the in vitro release studies. Detectable serum levels of PTX suggest that sustained release of drug was achieved in vivo. Minimal changes in subcutaneous tissue were observed at the site of injection. Future studies will further examine the localized and systemic distribution of drug following administration in this new polymer-based MP system.

Drug delivery to specific arms of the immune system can be technically challenging to provide prolonged drug release while limiting off-target toxicity given the limitations of current drug delivery systems. In this work, we test the design of a cyclodextrin (CD) polymer platform to extend immunomodulatory drug delivery via affinity interactions for sustained release at multiple size scales. The parameter space of synthesis variables influencing particle nucleation and growth (pre-incubation time and stirring speed) and post-synthesis grinding effects on resulting particle diameter were characterized. We demonstrate that polymerized CD forms exhibit size-independent release profiles of the small molecule drug lenalidomide (LND) and can provide improved drug delivery profiles versus macro-scale CD polymer disks in part due to increased loading efficiency. CD polymer microparticles and smaller, ground particles demonstrated no significant cytotoxicity as compared to the base CD monomer when co-incubated with fibroblasts. Uptake of ground CD particles was significantly higher following incubation with RAW 264.7 macrophages in culture over standard CD microparticles. Thus, the affinity/structure properties afforded by polymerized CD allow particle size to be modified to affect cellular uptake profiles independently of drug release rate for applications in cell-targeted drug delivery.