Replies to post #184439 on Biotech Values

[iwfal]

ISIS -

The dosing non-linearity still hasn’t been explained to my satisfaction (#msg-103128873, #msg-102371082).

Understood. Let me try somewhat more clearly:

0) Given that we have only three arms in the trial all we know for sure is that, if the data is real, there is non-linearity. Probably a threshold?

1) Many many biologic control systems have 'thresholds'. As long as the available level of hormone x is above Y then everything works pretty well. Once it drops below that level... . Glucose control classically behaves in that way with respect to insulin resistance and number of beta cells.

2) My more general point is that control loops often exist precisely to create thresholds and other non-linearities.

3) A point I have made many times on this board is that predicting even one moderately well understood control loop can be difficult. Predicting the behavior of a set of interconnected control loops, many very poorly understood, is a mugs game. Especially when the existence of some loops isn't even known.

The summation - I certainly would make no claims to be able to prove that FXI should work this way. But I think it is fairly plausible especially given FXI's role in an on-going battle between lysis and clot building.

PS The graphic you use is #msg-103128873 is, BTW, a good example of over-simplification of the system. It is definitely incomplete with regard to FXI.