Replies to post #6084 on GTC Biotherapeutics (fka GTCB)

[DewDiligence]

>Would you agree that survival at 90 days is a high predictor of a cure…<

In sepsis, if you’re alive at 90 days, you’re cured for all practical purposes. (The underlying condition that caused the acute problem might not be cured, of course.)

The FDA label for Xigris contains some data on long-term follow-up. Whatever positive or negative survival benefit was observed in the Xigris arm relative to the control arm at 90 days was observed out to one year:

http://www.fda.gov/cder/foi/label/2007/125029s080LBL.pdf

Regards, Dew

[jessellivermore]

Dear waynebro,

DIC represents an end stage of severe septcis which may be the result of other clinical problems and other forms of system failure. AT3 would not be a "cure." If AT 3 signifantly improves survival in a condition that is fatal in about half the cases, it would be embraced by the medical community. Septcis and DIC can occur in young healthy people sometimes from fairly innocuous factors eg. using tampons.

I do not know whether the subset was biased toward "surviors". My impression is it was not. Dew may know more about this. I think its a good question.

[DewDiligence]

Re: Kybersept data

>I guess my main concern is could the people that went into the AT3 without Heparin group had some difference that had a higher probability of survival.<

As you probably know (but others here may not), the allocation of Kybersept patients to the antithrombin arm vs the placebo arm was randomized and blinded from the investigators. On the other hand, the decision whether to use heparin was left to the discretion of each investigator in both the AT and the placebo arms.

Thus, the investigators could not have deliberately biased the AT vs placebo analysis by using or not using heparin because they were blinded as to which trial arm a patient belonged to. Whether the investigators could have unintentionally biased the AT vs placebo analysis is a fair question, however, and this is one reason the Kybersept no-heparin subset data ought not to be taken as the gospel.

In a year or so, we’ll have the results from Leo’s phase-2 trial, which will shed considerably more light on the safety and efficacy of AT in this setting. Regards, Dew