Impact of microsampling on toxicological evaluation in rodent safety studies

Area of Science:

• Toxicology
• Pharmacokinetics
• Animal Welfare

Background:

• Growing global emphasis on animal welfare and the 3Rs (replacement, reduction, refinement) in drug development.
• Microsampling, involving the collection of small blood volumes, is gaining traction as a method to improve animal welfare.
• Advancements in analytical techniques, such as mass spectrometry, facilitate precise drug concentration measurements from minimal blood samples.

Purpose of the Study:

• To review the toxicological effects of microsampling in rodents (rats and mice).
• To assess potential influences related to drug administration, recovery periods, blood sampling sites, and volumes.
• To discuss the broader implementation of microsampling in toxicology studies and its contribution to the 3Rs.

Main Methods:

• Literature review of studies reporting toxicological influences of microsampling in rodents.
• Analysis of factors including drug administration, post-collection recovery, sampling site, and sample volume.
• Examination of current trends and future perspectives for microsampling in regulatory toxicology.

Main Results:

• Microsampling demonstrates minimal toxicological influence in rodents, even with drug administration or recovery periods.
• Variations in sampling site and volume generally do not introduce significant confounding toxicological effects.
• The application of microsampling in regulatory toxicology is increasing, albeit slower than in discovery phases.

Conclusions:

• Microsampling is a valuable tool for enhancing animal welfare and supporting the 3Rs in nonclinical drug development.
• Its adoption in regulatory toxicology studies, where animal numbers are higher, offers substantial potential for animal number reduction.
• Further promotion and implementation of microsampling in toxicology studies are recommended to maximize benefits for animal welfare and scientific efficiency.