Replies to post #206684 on Biotech Values

[poorgradstudent]

PRTO:

Re: treatment of RCF vs BCF

1) They disagree. There are many reasons for why PRTO's Vonapanitise may work better for radiocephalic AVF's vs brachiocephalic AVF's. The primary reasons are condition of patients ( comorbidities eg hypertension ) vessel injury , vessel wall thickness , elastin content in basillic vs lower arm cephalic veins .

Given the turnover of the enzyme (~10/s) and the amounts of used, these factors are normalized. 10 to 30 ug of an active enzyme in a ~2-3 mm thick wall is a heroic dose. I can tell you this from personal experience.

Also, I would suggest that they look at the data. If the thickness / elastin content in the two veins were a significant factor in the enzyme treatment (and, therefore, the RCF vs BCF discrepancy), then there would be a significant difference in the % change in vein lumen diametre before and after enzyme treatment of RCF vs BCF fistulas. There isn't.

Further, in their presented data, the baseline vein lumen diametre differences in between the RCF and BCF groups are not meaningfully different. That suggests strongly that the vessel wall thickness isn't meaningfully different either.

Also, if wall thickness / relative content of elastin in the two fistula areas were different, then their post-hoc data analyses would have shown that a lower dose works for RCF but a higher dose for BCF. This would be a rational outcome of the drug's method of action, and would have shown up given the numerous dose levels they tested. It didn't.