On a generally sanguine day during which the Dow Jones Industrial Average (INDEX: ^DJI) was up 45 points, it was startling to witness the carnage inflicted upon certain stocks in the health-care sector. For instance, Avanir Pharmaceuticals (Nasdaq: AVNR) saw shares plunge 7%, continuing its slide this week after reporting earnings that the market didn't appreciate. YM Biosciences (NYSE: YMI), which was up 15% after encouraging results for myelofibrosis drug CYT387, retreated 9%, giving back a chunk of those gains.

Let's highlight 3 biotechs made even more dramatic negative moves today.

Company

Change in Price

BioSante (Nasdaq: BPAX) (77.4%)
Antares Pharma (AMEX: AIS) (30.7%)
InterMune (Nasdaq: ITMN) (30.3%)

Biosante's sexual dysfunction drug, LibiGel, works -- just not significantly better than the placebo it faced off against in phase 3 trials. Without strong efficacy data, FDA approval is essentially out the window. Antares Pharma was not immune to facing investors' wrath over LibiGel's failure, as Biosante uses Antares' gel to deliver its medication. The condemnation of Anteres is probably overblown; the company also has its delivery system licensed out to Jazz Pharmaceuticals (Nasdaq: JAZZ), which suffered no ill effects today. BioSante's management is taking time to regroup and figure out how to proceed with LibiGel and the company. They have a relatively strong balance sheet for a micro-cap biotech, and cash burn should slow, so buying an early-stage drug candidate to restock the pipeline might be the direction they are headed.

InterMune's drug pirfenidone treats a life-threatening lung disease, IPF, but can't get approval in the U.S. The FDA was concerned that only half of the company's phase 3 trials came back with positive results. Shares plunged 75% when the FDA said the company would need to run an additional trial before approval, overriding the advisory panel's narrow recommendation for approval.

Although the drug is approved in Europe under the name Esbriet, Intermune's latest rejection came from Germany's health organization, which recommended to the country's reimbursement authority that the drug holds "no or low additional benefit." Ouch! Analysts expect Esbriet to notch sales over half a billion dollars in 2014, but it's unclear over how much a setback this could be to that target.

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