Plucked Hair Biomarkers
Epistem has developed an innovative, highly sensitive, non-invasive plucked hair biomarker platform that measures gene changes within a single plucked human hair. Hair follicles are highly sensitive to therapeutic agents, including radiation and chemotherapy, with gene changes apparent within hours of exposure or dosing.

Epistem’s biomarker platform is used in both the preclinical and clinical phases.

Preclinical Biomarker Discovery and Identification
During subcutaneous xenografting studies, RNA is extracted from hair follicles and amplified into cDNA using Epistem’s propriety technology. Gene expression profiling is performed (qRT-PCR and Gene Chip analysis) on the RNA from excised tumours and hair follicles. The discovery and identification of gene sets that potentially predict efficacy, drug exposure and toxicity are identified and progressed to Phase I clinical trials.

Clinical Biomarker Platform
Single hairs are plucked from human subjects before and after treatment in Phase I. RNA is extracted from hair follicles and amplified into cDNA using Epistem’s propriety technology. Gene expression profiling is performed (qRT-PCR and Gene Chip analysis) and a core gene set identified that has the potential to demonstrate:

• Drug exposure – the level of drug and time required to effect signaling pathways
• Dose and schedule – duration of drug effects over dose ranges and time
• Early indications of toxicity (maximum tolerated dose (MTD) indications)
• Biological activity – as a surrogate marker to indicate tumour regression
  
  

Epistem is also developing other biomarker platforms including:

• Immunohistochemistry (IHC) analysis of human plucked hairs
• IHC and qRT-PCR from skin biopsies
• IHC and qRT-PCR on tumour derived samples