Biotech Values

[Summer2762]

EXEL.

In the same exact indication, at similar (but not exact) # of events (387 of 578 vs 305/365 of 511), cabazitaxel pivotal trial which met its study objective by showing a hazard ratio of 0.70 p < 0.0001 but also failed its interim.

The second interim analysis
was added after a protocol amendment to be
performed at the time of the 307 deaths (the 60%
of the 511 deaths in the final analysis of the
protocol) to assess the primary efficacy endpoint of
OS based on the O’Brien-Fleming type I error
spending function. The actual number of deaths at
the second interim analysis was 365 instead of 307.
Therefore, the type I error of the second and final
analyses were adjusted according to the O’Brien-
Fleming type I error spending function. The
corresponding statistical significance levels for the
interim analysis and the final analysis of OS were
0.0160 and 0.0452, respectively.

http://www.accessdata.fda.gov/drugsatfda_docs/nda/2010/201023Orig1s000StatR.pdf

I just read the related PR.

http://www.exelixis.com/investors-media/press-releases?cpurl=http%3A%2F%2Fir.exelixis.com/phoenix.zhtml?c=120923%26p=irol-newsArticle%26ID=1912367%26highlight=

The PR does not state the reason why DMC recommended continuation.

Similarly we do not know whether cabazitaxel hit its required significance level at interim or DMC was worried about AEs and recommended continuation.