Drug Firm Kicks Into Higher Gear; Idenix Pharmaceuticals; Cambridge, Mass. idenix.com.(HEALTH & MEDICINE)(UNDER THE MICROSCOPE)

Byline: Peter Benesh

Jean-Pierre Sommadossi is in a race. The chief executive of Idenix Pharmaceuticals wants to get his company's hepatitis C drug approved by the Food and Drug Administration and on the market before his competitors catch up -- or pass him.

Idenix's drug, labeled NM283, is a pill. In combination with other treatments, it's shown promise in early tests among hepatitis C patients who didn't respond to current therapy. The drug's potential is enormous, analysts say.

"If you shorten treatment to three months and increase recovery chances to 80% to 90%, you can charge a ton for that," said Andrew McDonald of ThinkEquity Partners.

Sommadossi puts the global market opportunity at $3 billion to $5 billion a year. Current treatments have grim side effects, he says, including blood poisoning, anemia, flu like symptoms, fatigue and nausea.

Idenix's Achilles' heel is its reliance on a combination of drugs to do the job, McDonald says. NM283 requires a protease inhibitor -- a drug that interferes with virus replication.

"The big question is, "Will the (hepatitis C) breakthrough be a combination therapy or a stand-alone?' " McDonald said.