Summary

What are biomarkers?
Regulatory agencies are increasingly demanding objective tests that measure pharmacologic responses to a new drug during clinical development. Biomarkers inform clinicians on drug exposure, dose and scheduling, toxicity, and patient selection.

New generation oncology drugs target specific cellular pathways to kill tumours. Since tumours are difficult to access, drug effects need to be measured indirectly on surrogate tissues.

The hair follicle as a surrogate tissue in oncology
The hair follicle is a highly vascularised epithelial tissue, which makes it an attractive surrogate tissue in oncology since over 80% of adult tumours are epithelial in origin.  The follicle is a highly organised structure with cell production underpinned by stem cells in the follicle.

Epistem’s co-founder, Professor Chris Potten, discovered in the 1970s that very low levels of radiation or chemotherapy kill stem cells in the small intestine and hair follicles. This observation of the biological linkage of stem cells in these two tissues led to a series of reports by the Potten laboratory demonstrating that the hair follicle responds toxicity in a dose-linear manner.