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.

Let's take a closer look at three health care stocks -- Dendreon (NASDAQ: DNDN), AbbVie (ABBV 0.25%), and Omeros (OMER -3.89%) -- which could loom large in health care headlines this morning.

Dendreon announces the European launch of Provenge
The first stock investors should check today is Dendreon (NASDAQ: DNDN), the maker of the prostate cancer immunotherapy drug Provenge. The stock surged nearly 15% yesterday after reporting better-than-expected fourth quarter earnings, but it could move even higher this morning in response to Dendreon's (NASDAQ: DNDN) European launch of Provenge.

Provenge was approved in Europe last September, and Dendreon (NASDAQ: DNDN) inked a deal with PharmaCell the following month to be the Contract Manufacturing Organization (or CMO) for Europe. Dendreon (NASDAQ: DNDN) will initially launch the drug in the United Kingdom and Germany.

Provenge primarily competes against Johnson & Johnson's (JNJ 0.67%) Zytiga and Medivation/Astellas' Xtandi, which have both been approved in the U.S. and Europe. Provenge was pegged to hit peak sales of $3 billion to $4 billion when it was launched in the U.S. in 2010, but those estimates were revised downward when it became clear that Wall Street had overestimated the drug's sales potential.

In fiscal 2013, Dendreon (NASDAQ: DNDN) reported $283.7 million in Provenge sales, a 13% decline from the previous year. Whether the European launch will reverse that decline is unclear, but investors should note that global sales of J&J's (JNJ 0.67%) Zytiga, its biggest competitor, rose 76.7% year over year to $1.7 billion in fiscal 2013.

Despite its recent rally, shares of Dendreon (NASDAQ: DNDN) are still down more than 40% over the past 12 months.

AbbVie's hepatitis C combo cures 99% of patients in a late-stage trial
Our second story this morning involves AbbVie (ABBV 0.25%), which announced yesterday that its combination hepatitis C treatment cured 99% of 419 patients in a late-stage trial after 12 weeks of treatment, regardless of whether the older hepatitis C drug ribavirin was taken with the cocktail.

The combo consists of a protease inhibitor known as ABT-450, an NS5A inhibitor called ABT-267, and the non-nucleoside polymerase inhibitor ABT-333. Jefferies International analyst Jeffrey Holford forecasts that ABT-450 could generate peak sales of $1.4 billion by 2016, becoming the company's second best-selling drug after the rheumatoid arthritis drug Humira, which generated $10.7 billion in global sales (57% of AbbVie's (ABBV 0.25%) revenue) in fiscal 2013.

If AbbVie's (ABBV 0.25%) cocktail is approved, it will compete against Gilead Sciences' (GILD -1.15%) Sovaldi and Bristol-Myers Squibb's combination treatment of daclatasvir, asunaprevir, and BMS-791325. Wall Street has high hopes for both treatments -- Sovaldi, which was approved last December, could hit peak sales of $7 billion, while Bristol-Myers' combination treatment, which is expected to launch in 2016, could generate peak sales of $1.2 billion.

Omeros submits an IND application to initiate a phase 2 program for OMS721
Last but not least, Omeros (OMER -3.89%) just announced the submission of an IND (investigational new drug) application to initiate a phase 2 clinical program for OMS721, the company's lead human monoclonal antibody candidate. Last month, Omeros (OMER -3.89%) announced positive data after the completion of a phase 1 clinical trial of OMS721, which was granted an orphan drug designation by the FDA last December.

OMS721 is intended to prevent complement-mediated thrombotic microangiopathies (TMAs), a rare disorder that causes multiple clots to form in the body's organs, most commonly in the kidney and the brain.

Investors should note that OMS721 is not the company's most advanced product. Omeros (OMER -3.89%) has already submitted an NDA (new drug application) and MAA (marketing authorization application) for OMS302, a treatment for ophthalmological procedures. OMS103HP, which is intended for arthroscopy and menisectomy procedures, is currently in phase 3 trials. Omeros (OMER -3.89%) does not currently have any marketed products.

Another key drug candidate, OMS824, has shown promise during phase 1 trials in inhibiting the production of an enzyme, which has been implicated in brain diseases such as Huntington's disease and schizophrenia. Although a market approval for OMS824 is still years away,some analysts anticipate that the drug will generate peak sales of $1 billion if approved.

Investors are optimistic regarding the growth potential of Omeros' (OMER -3.89%) pipeline, and its stock has climbed more than 100% over the past 12 months.