found at:
http://invivoblog.blogspot.com/

Idenix Pharmaceuticals announced this morning that FDA had placed a clinical
hold on its Phase II valopicitabine hepatitis C polymerase inhibitor.  July
13, 2007

FDA made its decision following an assement of the overall risk benefit
profile observed in clinical rials to date, according to Idenix CEO JP
Sommadossi, who addressed analysts on a conference call today. "We were very
surprised," he said, adding that along with its partner Novartis, Idenix is
evaluating its options. "But i am not optimistic about further development
of valopicitabine in the future," Sommadossi added, and later re-emphasized.

So what happened? "FDA looked at all of the Phase IIB data ... and concluded
that the GI side effect profile was not commensurate with the antiviral
activity we were seeing," said Doug Mayers, CMO. Idenix, the executives
said, had seen similar signals such as nausea and vomiting, but were eager
to play with the doses of valopicitabine in further trials in an attempt to
find a workable risk/benefit profile. FDA had different ideas.

Valopicitabine, previously dubbed NM283, was the furthest-along HCV
polymerase inhibitor in clinical development and the first of a
next-generation set of targeted HCV therapies. The polymerase class hasn't
received as much attention as HCV protease inhibitors, which have been the
subject of some pretty sizeable deals--Vertex's alliance with Johnson &
Johnson and Intermune's alliance with Roche, for example. But Idenix had
maintained that the future of HCV antiviral therapy would be combination, a
sentiment shared by many, and so pushed ahead with development despite only
moderate clinical success with the compound.

The biotech's partner Novartis must have agreed; the companies have a broad
alliance whereby Novartis gets first right of refusal on any Idenix compound
when it hits Phase II. For valopicitabine, Novartis had to pony up more than
half a billion dollars to maintain its share of the drug. Novartis owns
upwards of 57% of Idenix.

Today's news is the second clinical hold placed on a Novartis-in-licensed
HCV candidate this year. Last summer FDA halted trials of Anadys' ANA975
drug, a TLR-7 agonist in Phase Ib, after a preclinical toxicology study
unearthed a potential safety signal.

HCV dealmaking has definitely been a hot space, and will likely continue to
be so despite this spate of clinical difficulties. For our roundup of drugs
in development for HCV, see this late-2005 IN VIVO story.

UPDATE: Idenix shares are off about two bucks, or 35%, at about 11:30a.
Labels: clinical development, FDA, hepatitis C, Idenix, Novartis

posted by Chris Morrison at 10:05 AM 0 comments

Yup. The writing was on the wall from the 2007 EASL presentations.
It was clearly doomed...

/greyhackles