Idenix suffers another FDA-mandated clinical hold...

Posted 8/27/12 on Fierce Biotech.com. Idenix suffers another setback as the FDA puts its NS5B inhibitor, IDX19368 on clinical hold as the fallout from the AE's from BMS-094 continue. Both IDX184 and IDX19368 are in the same class of nucs as the ill-fated BMS-094 and share the same active metabolite. Idenix CEO Ron Renaud feels there is enough differentiation between BMS-094 and the Idenix compounds to put safety concerns to rest, but the company is doing its due diligence in terms of ensuring the safety of the patients enrolled in its trials. The clinical holds certainly slow down the development of Idenix's nucs, but hopefully Mr. Renaud is right and the Idenix compounds still hold market potential. 

Idenix plunges after FDA puts another hep C treatment on hold

August 27, 2012 | By John Carroll

Idenix already faces a partial clinical hold on its top hepatitis C program. Now the FDA has stepped in to add a clinical hold on its preclinical therapy IDX19368, another nucleotide polymerase inhibitor, or "nuc," in the pipeline. The biotech ($IDIX) also spelled out some added safety checks for its lead hep C treatment, which the company says can be completed in a matter of weeks. But its shares swiftly plunged on the fresh round of troubling news.

"Based on our discussions with the FDA, we understand the clinical hold is a precautionary decision made by the FDA in light of the adverse events seen with BMS-986094," said Idenix CEO Ron Renaud. "Both IDX184 and IDX19368 fall into the same broader class of NS5B inhibitors, and share the same active metabolite as BMS-986094. However, there are many attributes of our compounds, particularly the prodrug approach, that we believe favorably differentiate the toxicity profiles from that of BMS-986094."

Idenix's FDA woes were triggered by the abrupt failure of BMS-094, a once sizzling-hot hep C treatment which raised alarms after one patient died and 8 others in a study were hospitalized, just 8 months after Bristol-Myers Squibb paid $2.5 billion to acquire Inhibitex. Bristol ($BMY) announced on Thursday that it was writing off $1.8 billion and scrapping the drug entirely. Idenix added today that BMS is lending a hand in resolving the holds.

Idenix also reported that it has lined up ethocardiograms for 50 patients enrolled in its IDX184 study. A few done so far have not revealed any safety concerns and the developer says that it should be able to complete this process in a few weeks.

A lingering concern for Idenix, though, is whether the company can regain the glow that had enveloped it after some big deals in the hepatitis C space made the company a prime takeover target, with analysts speculating about the prospect for a big premium. The Cambridge, MA-based company has been among the leaders in the mad scramble to advance new "nucs" and NS5A inhibitors that can be combined with ribavirin into an all-oral regimen with megamarket potential.

Idenix shares plunged 40% on news of the partial hold 11 days ago. This morning the stock plunged another 16% in premarket trading. Both of these programs are unpartnered, which leaves Idenix holding the bag now for any long-term loss in value.