Fariba G. asks, "Interesting analysis of microcap stock and trial outcome. Was the bearish view of Dr. Ratain based on this statistics or did he bring scientific backing for his view?"
"Finland64" emails, "It would be great if you could take some time to write that article on the flaws (and perhaps the strengths) in the perifosine phase II colon cancer trial…Would it also be possible for you to include the fact that it was a controlled, randomized, double blinded study?"
The strongest, most reliable, clinical data comes from randomized, controlled studies. No disagreement there. I've long criticized biotech companies that run crappy single-arm phase II studies and then make dubious survival-benefit claims based on comparisons to outdated "historical" data. Blech.
Ratain has also been a vocal proponent of randomized studies and believes the high failure rate in cancer drug development stems, in large part, from the over-reliance on single-arm trial designs.
As he says above, Ratain also believes the perifosine phase II study is flawed, despite what looks to be a randomized, controlled clinical trial design.
As originally conducted, the phase II study was designed to determine perifosine's signal of activity. Initially, 381 patients diagnosed with seven different types of cancer and treated with eight separate chemotherapy regimens were to be enrolled in the study. Within each tumor type, patients were to be treated with either perifosine or a placebo.
Full enrollment in the study never took place. Instead, an unplanned interim analysis was conducted which revealed evidence of clinical activity when perifosine was combined with capecitabine (sold by
under the brand name Xeloda) in 25 colon cancer patients. Based on this unplanned analysis, the original study design was abandoned and instead, an additional 13 colon cancer patients were enrolled in the study to bring the total number of colon cancer patients to 38.
It's data from these 38 colon cancer patients -- which again, purports to show a survival benefit favoring the perifosine-capecitabine combination over capecitabine alone -- that Keryx relied upon to design the ongoing phase III study.