@JB1975. Biomarker determination“Samples were shipped to a...

@JB1975. Biomarker determination

“Samples were shipped to a central laboratory, where ST2 and REG3α were analyzed by enzyme-linked immunosorbent assay in batches, as previously described.^6,15 The concentrations of ST2 are reported as picogram per milliliter and of REG3α as nanogram per milliliter. The MAP is calculated as a single value between 0.001 and 0.999 according to the formula: log[–log(1 – MAP)] = –11.263 + 1.844(log₁₀ST2) + 0.577(log₁₀REG3α).¹⁵ At the start of GVHD treatment, 2 thresholds divide MAPs into 3 separate groups with different NRMs, termed the Ann Arbor score.¹⁵ Ann Arbor 1 is defined as MAP < 0.141, Ann Arbor 2 as 0.141 ≤ MAP ≤ 0.290, and Ann Arbor 3 as MAP > 0.290. Following treatment, a single threshold (0.290) divides MAPs into 2 groups with significantly different NRMs.⁶ This validated scoring system of prognostic biomarkers is now widely used and commercially available. Missing biomarker data for patients who died before 4 weeks of treatment were imputed by carrying forward the last measurement before death. If data were missing for reasons other than early death, no imputation was made.”

https://www.researchgate.net/publication/337844503_The_MAGIC_algorithm_probability_is_a_validated_response_biomarker_of_acute_graft-versus-host_disease

The link and slides which were presented by Mesoblast @Biotech Showcase in January 2022 …show that the biomarkers MBS, MAP which are an independent statistically accurate measure for predicting high risk mortality (p <0.001). These results , prove that Mesobalst were able to achieve partial and complete responses in the most difficult to treat patients with an reading above the critical AUC of 0.29 . The key serum biomarkers referenced in the algorithm are ST2 and Reg 3a . This research only becomes available post our BLA CRL…and it shows that Mesoblast was able to outperform all recognised standard of care in what is typically considered “non responders” with very poor prognosis. ST2 is considered by many to be much more reliable as a biomarker than the 2 clinical grading systems used to classify patients (BMITR and Glucksberg)

Hope this helps.

OP