Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

Good morning, fellow Fools! Time to check in on today's mover and shakers in health care.

Avanir bouncing back?
Avanir Pharmaceuticals (NASDAQ: AVNR) shares are rebounding 11% this morning after falling by as much as 30% Wednesday upon releasing its fourth-quarter earnings report.

Although net revenue for Avanir's FDA-approved pseudobulbar affect drug Nuedexta increased by 12% from the third quarter, the company's operating losses continued to climb. Specifically, Avanir reported a net loss of $15.4 million, or $0.10 per share, last quarter.

The main problem facing the company is that operating expenses exceeded $36 million for the quarter, with the bulk of these expenses resulting from increased research activities to expand Nuedexta's current label. So despite steadily increasing revenues from Nuedexta sales, operating losses continue to weigh heavily on Avanir's bottom line.

My take is that this drop was an overreaction for the most part and may represent an intriguing buying opportunity for investors with a long-term outlook.

AstraZeneca and Bristol-Myers receive good news from advisory panel
AstraZeneca (NYSE: AZN) and Bristol-Myers Squibb (NYSE: BMY) could both be on the move today after the Food and Drug Administration's Endocrinologic and Metabolic Drugs Advisory Committee, or EMDAC, recommended approval for the companies' experimental drug metreleptin as a treatment for pediatric and adult patients with generalized lipodystrophy, or LD. Lipodystrophy is a rare disorder caused by either genetic or environment factors, and is characterized by a loss of fat in certain areas of the body, especially the face.

The panel voted 11-1 in favor of the drug's use in patients with generalized LD, but 2-10 against its proposed use in patients with limited LD. Even so, AstraZeneca and Bristol-Myers will continue to petition the FDA to allow the drug's use in patients with limited LD. Although the panel did recommend the drug, it's important to remember that the FDA is not bound to EMDAC's recommendation. The final decision is expected around Feb. 24.

Why is this possible approval a big deal? Metreleptin has been granted the coveted orphan drug status by the FDA. So even though the drug's target market consists of only a few thousand patients worldwide, the drug will receive a number of important benefits such as tax breaks and extended market exclusivity upon approval. Similar benefits have helped a number of orphan drugs go on to become blockbusters despite treating limited patient populations.

VIVUS looking up
VIVUS (NASDAQ: VVUS) is up about 2.5% this morning after announcing a License and Commercialization Agreement with Sanofi for the company's erectile dysfunction drug Avanafil. Per the terms of the agreement, VIVUS will receive up to $61 million in upfront and milestone payments in exchange for the commercial rights to the drug in Africa, the Middle East, Turkey, and Russia.

What's my take? I think this licensing agreement will give VIVUS some much needed breathing room. Although VIVUS's obesity medication Qsymia has seen improving sales of late, management has openly stated its desire to find a marketing partner for the drug, especially in light on increasing sales for Arena Pharmaceuticals' Belviq and the possible commercial launch of Orexigen Therapeutics' Contrave next year. So this licensing deal should help alleviate the pressure on Qsymia sales and allow VIVUS to find the right partner for the drug going forward.

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George Budwell has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.