These last two months haven't been good for drug developer Idenix Pharmaceuticals (NASDAQ:IDIX). Following on the heels of negative data for its lead hepatitis C (HCV) drug candidate, valopicitabine, Idenix announced that the FDA put a stop to testing of the drug last week.

Idenix announced disappointing phase 2 results for valopicitabine last month, but not so disappointing that they seemed to merit cessation of trial. However, based on these trial results and the "overall risk/benefit profile" of the drug, the FDA put the kibosh on further testing of valopicitabine. Idenix's management also stated that they were "not optimistic" about being allowed further testing of valopicitabine in the future, so investors shouldn't expect to see this drug in the clinic again.

With the end of clinical testing of this compound, Idenix is left with an approved hepatitis B compound, Tyzeka, co-marketed with partner Novartis (NYSE:NVS), that is expected to bring in $20 million in milestone payments this year, and a drug pipeline completely devoid of interesting late-stage compounds.

Idenix is still guiding to end the year with $100 million to $110 million in cash and does plan to move forward with phase 1 and preclinical studies of other HCV and HIV drug candidates. With this large cash hoard, minimal debt, and revenue from Tyzeka set to start coming in, shares of Idenix still have some value even without valopicitabine, but whether Tyzeka is enough to justify its $200 million market cap is questionable.

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article.