Cell Therapy News/Articles, page-8826

At the risk of replying to my own comment I haven't been able to sleep thinking about this part of the article that Chau found

https://stemcellsjournals.onlinelibrary.wiley.com/doi/epdf/10.1002/stem.3380

Dr Galipeau uses the word 'cornerstone' which probably underplays how important this could be for Mesoblast - this could be the discovery that answers primary questions raised by the FDA in the CRL for sr-GvHD regarding MOA and potency of the cells - as per the CRL "The FDA stated the need for additional scientific rationale to showcase the relationship of potency measurements to the agent’s biologic activity, according to Mesoblast."

And as per the Dr Galipeau's paper (highlighting is mine)

"Mapping of such markers is of value for defining plausible in vivo correlative mechanism of action which further strengthens the path towards marketing approval by regulatory agencies [7]. Indeed, the FDA guidance on potency testing for Potency Tests for Cellular and Gene Therapy Products† aspirationally seeks for mapping of a relationship between potency and clinical effectiveness where “clinical data may be used to establish a correlation(s)between biological activity and a more practical potency measurement(s) that can be used for lot release, stability, and/or comparability studies”. The MSC/monocyte functional dyad may provide correlates that meet the regulators test of coupling MSC quality attributes [such as IDO, COX2, TSG-6 or chemokine expression] and host monocyte/macrophage response as surrogate biomarkers of pharmaceutical activity"