Custom Infection Model Development: What to Expect
Before beginning in vivo efficacy work with a new client at TransPharm Preclinical Solutions, we usually offer to run a validation study first. This is useful because it allows us to reaffirm the stability and robustness of our models cheaply and quickly, as well as confirm the virulence of the pathogen that we plan to use for the client’s studies. With how expensive efficacy studies can be, which may involve many mice, several test articles, multiple timepoints, and/or hundreds of samples being taken, it’s critical to have confidence beforehand that a current model still works, or that a new custom infection model will work.
An example of when it would be appropriate to run one of these studies would be when we receive a new pathogen. Depending on the model we plan to use the strain for, we may run an LD50 or LD100 validation study. These are multi-log challenge studies where each group of animals is challenged with a different concentration of the pathogen, which are typically 1:10 dilutions of each other. They can range from as low as 1log and go up to 9log, if desired, although we typically pick a range of 5logs in most scenarios.
The LD50’s purpose is to provide an exponential curve of mortality that shows a correlation between higher log levels of infection with more mortality, as well as the concentration of pathogen that would result in 50% mortality in the infected groups. An LD100 may provide a mortality curve as well, but its primary purpose is to show the challenge level(s) where the pathogen is 100% lethal in test subjects. The data from these kinds of studies helps inform us of the appropriate challenge level to use in the efficacy studies for the client based on the design and desired outcomes of the study.
Performing validation studies is one of the ways that TransPharm Preclinical Solutions goes above and beyond to forge a strong relationship with its clients built around trust and transparency. We want to streamline the drug development process for you and cut down on unnecessary costs, while providing you with the most reliable data for your drug candidates! Feel free to reach out to us for more information or any questions you may have. We’re here for you!