3 Recent Developments in Toxicity Testing

Toxicology refers to the study of chemical substances that cause harm to biological organisms. They can be present in pharmaceutical drugs, food additives, cosmetics, pesticides, agricultural chemicals, and other products. Exposure to these toxic chemicals can occur through skin contact, oral intake, or inhalation. Therefore, testing of these chemicals is crucial to determine the degree of toxicity in products. It ensures that the products used are completely safe and will not pose any harm to human health or the environment. Toxicity testing can be done in various ways including in vivo testing, in vitro testing and in silico testing. In vivo toxicity testing is carried out on animals, in vitro testing is performed in laboratories using assays, and in silico testing is performed on a computer.

The early toxicity testing market is witnessing a robust growth in recent years owing to the growing stringency of regulatory authorities concerning the welfare of the environment and public health and the need to avoid financial losses due to drug failure in the later stages of development. Allied Market Research states that the early toxicity testing market is expected to grow at a compound annual growth rate (CAGR) of 7.3% from 2016 to 2022. Several developments in the space are leading to market growth. In June 2018, Creative Animodel, a bioscience contract research organization (CRO) which provides preclinical services such as pharmacodynamics (PD), pharmacokinetics (PK), and toxicology services recently announced its plans to expand its lab services to include in vivo toxicology for drug screenings and other analyses. In May 2018, CN Bio Innovations Limited, a UK-based biotechnology company introduced an organ-on-a-chip device called PhysioMimix that enables scientists to test drugs on living human organ models. In March 2018, a test for inhalation toxicity called EpiAirway was launched by XCellR8, a world leader in non-animal testing.

Here we take a more detailed look at these developments.

Creative Animodel Expands Lab Services

Creative Animodel announced its decision to expand its lab services with the aim of incorporating in vivo toxicology for drug screenings, secondary analysis and its techniques to identify candidate drugs. According to the company, the expansion brings a much-needed service to the region and provides acute and chronic toxicity assays faster with accurate results. The expansion also provides a more comprehensive report summary for toxicity, including PK, PD, urinalysis, chemistry, and histopathology results. Jenney, director of the company’s R&D department said that they would assist their clients in accelerating the process of in vivo toxicology study through their preclinical services. She also added that their lab technicians would be well-trained to use highly advanced equipment that would lead to more timely results.

CN Bio Innovations Launches an Organ-on-a-chip Device

PhysioMimix allows scientists to perform organ-on-chip studies in cell culture labs without using animal models. The device enables tests to be performed with new potential drugs on living human organ models. Powered by technology licensed from the Massachusetts Institute of Technology, PhysioMimix features open-well plates which allow the formation of micro-tissues that look and behave like human organs and tissues. Moreover, several devices can be linked with the help of small fluid-filled channels to analyze the interaction of organs with one another as well as their response to stimuli. PhysioMimix also has the advantage of being fast to install in cell culture labs. The open-well system allows easy introduction of primary cells, stem cells or pre-formed tissues to develop the organ mimics and remove samples for analysis during an experiment.

Test for Inhalation Toxicity by XCellR8

XCellR8’s EpiAirway model was created by using human bronchial and tracheal cells to reconstruct the airway epithelium like that of humans. It has beating cilia at the epithelial surface and can produce mucus. Whilst performing tests for inhalation toxicity, chemicals or formulations are introduced onto the EpiAirway model’s surface. To prevent excessive evaporation of volatile substances, a cap is used where required. After a three-hour exposure in a cell culture incubator, the substance under test is removed by gentle washing. Any harm that is caused to the cells is calculated by their ability to metabolize a dye (MTT) into a purple product, which is measured using a spectrophotometer. The level of toxicity is measured by calculating an ‘IC75’ value - the concentration required to minimize the viability of the cells in the EpiAirway model to 75% compared with a negative control treated with water. Items with an IC75 value below a threshold are considered as toxic to the human airway. The model has been widely used as a research tool.