Advanced tissue technologies of blood-brain barrier organoids as high throughput toxicity readouts in drug development.

Recent advancements in engineering Complex models (CIVMs) such as Blood-brain barrier (BBB) organoids offer promising platforms for preclinical drug testing. However, their application in drug development, and especially for the regulatory purposes of toxicity assessment, requires robust and reproducible techniques. Here, we developed an adapted set of orthogonal image-based tissue methods including hematoxylin and eosin staining (HE), immunohistochemistry (IHC), multiplex immunofluorescence (mIF), and Matrix Assisted Laser Desorption/Ionization Mass Spectrometry Imaging (MALDI-MSI) to validate CIVMs for drug toxicity assessments.

The development and qualification of liquid adsorption chromatography for poloxamer 188 characterization.

Poloxamer 188 (P188) is formulated in proteinaceous therapeutics as an alternative surfactant to polysorbate because of its good chemical stability and surfactant properties, which enable interfacial protection, preventing visible and sub-visible particle formation. However, due to the nature of polymer heterogeneity and limited analytical approaches to resolve the superimposed components of P188, the impact of its quality variance on protein stability is still not well understood. In this study, we developed an analytical method to evaluate the components of P188 as a function of the length of polypropylene oxide (PPO), by maintaining polyethylene oxide (PEO) at the critical point of adsorption (CPA) to eliminate its chromatographic interference.

Safety, Tissue Distribution, and Metabolism of LNA-Containing Antisense Oligonucleotides in Rats.

Antisense oligonucleotides (ASOs) are chemically modified nucleic acids with therapeutic potential, some of which have been approved for marketing. We performed a study in rats to investigate mechanisms of toxicity after administration of 3 tool locked nucleic acid (LNA)-containing ASOs with differing established safety profiles. Four male rats per group were dosed once, 3, or 6 times subcutaneously, with 7 days between dosing, and sacrificed 3 days after the last dose.

Multiorgan Crystal Deposition of an Amphoteric Drug in Rats Due to Lysosomal Accumulation and Conversion to a Poorly Soluble Hydrochloride Salt.

Poor solubility of drug candidates mainly affects bioavailability, but poor solubility of drugs and metabolites can also lead to precipitation within tissues, particularly when high doses are tested. RO0728617 is an amphoteric compound bearing basic and acidic moieties that has previously demonstrated good solubility at physiological pH but underwent widespread crystal deposition in multiple tissues in rat toxicity studies. The aim of our investigation was to better characterize these findings and their underlying mechanism(s), and to identify possible screening methods in the drug development process.

Application of Imaging Techniques to Cases of Drug-Induced Crystal Nephropathy in Preclinical Studies.

A number of drugs can cause precipitates within renal tubules leading to crystal nephropathy. Crystal nephropathy is usually an exposure-related finding and is not uncommon in preclinical studies, where high doses are tested. An understanding of the nature of precipitates is important for human risk assessment and further development.