Exosomal protein and HER 2-3 dimer analysis
PD
DISEASE
Exosomes from plasma of 13 patients before and after their first dose of AZD8931 were extracted and analysed for proteins of interest and HER2-3 dimer quantity. Plasma-derived exosomes were characterised by the presence of exosome surface marker proteins CD63 and ALIX. HER proteins were consistently detected from circulating exosomes and their quantities changed with treatment (Supplementary Fig. Dimer score changes before and after first dose of AZD8931.We observed changes in HER markers (Table Protein expression changes before and after first dose of AZD8931.Two patients of the three who had a PR at 12 weeks had a decreased HER2-3 dimer score between those time points; no other patients showed this response. The one patient who had PD at 12 weeks had an increased HER2-3 dimer score and a decreased EGFR/HER-3; again no other patient had this response. All other patients had stable disease at 12 weeks and experienced no change in any dimer score.