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 Foolish investors! Let's take a closer look at four stocks that could make health care headlines this morning -- AstraZeneca (AZN -0.75%), Bristol-Myers Squibb (BMY -1.71%),  Clovis Oncology (CLVS) and Alexion Pharmaceuticals (ALXN).

AstraZeneca and Bristol-Myers Squibb win FDA approval for Farxiga

AstraZeneca and Bristol-Myers Squibb announced that the FDA had approved Farxiga (dapagliflozin), a once-daily oral drug to control blood sugar levels in patients with type 2 diabetes.

The drug was approved as Forxiga in Europe in November 2012, but had previously been rejected by the FDA in January 2012. Forxiga/Farxiga is part of a new class of diabetes drugs known as SGLT2 inhibitors, which help diabetes patients excrete more sugar through the urine.

Until now, Johnson & Johnson's Invokana was the only approved SGLT2 inhibitor on the market. Analysts believe that both Invokana and Farxiga can hit peak sales of $1 billion.

While Farxiga has now been approved in the U.S., investors should remember that J&J was asked to conduct five additional long-term studies on Invokana's effects on liver problems, heart problems, cancer, and pancreatic diseases following its approval in March 2013. It's likely that AstraZeneca and Bristol-Myers will be asked to conduct similar long-term studies as well.

Clovis announces its anticipated development milestones

Meanwhile, Clovis Oncology could jump today after the company announced its anticipated development milestones and financial guidance for 2014.

The company, which doesn't have any marketed products, currently has three clinical development programs under way.

The three key drugs to know for Clovis are CO-1686, a treatment for non-small cell lung cancer (NSCLC), rucaparib, a treatment for ovarian cancer, and lucitanib, a treatment for lung and breast cancers. CO-1686 is currently in phase 1 trials, while the other two have advanced to phase 2 trials.

CO-1686 is an interesting new treatment for NSCLC, since it targets a rare mutation known as T790M, which affects 15,500 patients in the United States. Since there are no approved treatments which specifically target the T790M mutation, analysts believe that CO-1686 could generate peak sales of $1.2 billion. Looking ahead into 2014, Clovis expects to initiate four different studies to test CO-1686 as a first, second, and later line treatment for NSCLC. It also intends to escalate the doses to determine the recommended dose for phase 2 trials.

Meanwhile, rucaparib also targets a specific mutation of ovarian cancer known as BRCA, a tough-to-treat mutation which affects 15% of ovarian cancer cases and 5% to 10% of breast cancer cases. In 2014, Clovis intends to initiate a phase 2 study for pancreatic cancer, and respectively commence and continue its phase 3 and phase 2 studies of the drug.

Lastly, lucitanib is an oral treatment which attempts to block growth signals in lung and breast cancers. In 2014, Clovis intends to initiate a phase 2 breast cancer study in the U.S. and a global phase 2 study for squamous cell lung cancer.

Clovis finished fiscal 2013 with $323 million in cash and expects to burn through $120 million in cash in 2014. This indicates that Clovis should have plenty of time to win approval for its drugs.

However, investors shouldn't get too excited yet -- after all, this is the same company that took investors on a roller coaster ride last year after the failure of its pancreatic cancer drug, CO-101.

Alexion signs a strategic agreement with Moderna Therapeutics

Last but not least, Alexion announcement an exclusive strategic agreement with Moderna Therapeutics to use the latter's Messenger RNA (mRNA) Therapeutics platform to develop new treatments for rare diseases.

Moderna's mRNA platform uses the body's own natural processes to stimulate the production of various proteins within the body, which could speed up the development of treatments for currently untreatable rare diseases.

Under the terms of the agreement, Alexion will pay Moderna an upfront payment of $100 million, which it gives it the options to develop and commercialize 10 products with the mRNA platform. If Alexion exercises these options, Moderna will also be entitled to additional milestone payments. Alexion also made a separate $25 million preferred equity investment in Moderna.

This deal could help Alexion diversify its pipeline, which only consists of four other treatments in addition to its only marketed product, Soliris.

Soliris, which is approved for two rare diseases -- paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic uremic syndrome (aHUS) -- generated $400.4 million in sales last quarter, a 36% jump from the prior year quarter. Analysts believe that Soliris could eventually generate annual peak sales of $3.5 billion, if approved for additional indications.

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