Today’s Top Biotech Stories: Mallinckrodt, Regeneron, Arena, and Omeros

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 Mallinckrodt (MNK), Regeneron (REGN -0.09%), and Arena Pharmaceuticals (ARNA), and Omeros (NASDAQ: OMER)-- all of which could loom large in health care headlines this morning.

Mallinckrodt buys Cadence Pharmaceuticals for $1.21 billion
First and foremost, health care products company Mallinckrodt just announced its acquisition of Cadence Pharmaceuticals (NASDAQ: CADX) for approximately $1.3 billion in cash to boost its specialty pharmaceuticals segment. Mallinckrodt will pay $14 per share for Cadence, a 27% premium to the company's closing price of $11.07 on Monday. Both companies' boards have unanimously approved the deal.

Cadence is best known for the intravenous painkiller and fever reducer Ofirmev, which the company estimates generated $110.5 million in revenue during the 2013 calendar year. Mallinckrodt reported $2.2 billion in revenues in fiscal 2013. Mallinckrodt expects the acquisition to immediately become earnings accretive in fiscal 2014, and significantly boost its adjusted earnings per share in fiscal 2015. The deal is expected to close in mid to late March.

Regeneron's 2013 revenue and earnings respectively surge 53% and 75%
Meanwhile, Regeneron reported its fourth quarter and full year earnings this morning. U.S. sales of the eye treatment Eylea, which accounted for 66% of Regeneron's full year revenue, rose 46% year-over-year to $402 million for the fourth quarter, and finished fiscal 2013 with $1.41 billion in sales -- a 68% jump from fiscal 2012.

The drug, which is currently approved for Wet AMD (age-related macular degeneration) and macular edema following CRVO (central retinal rein occlusion), primarily competes against Novartis' Lucentis and Roche's Avastin (off-label use). Yesterday, Regeneron announced that its phase 3 VISTA trial for Eylea as a DME (diabetic macular edema) treatment was progressing well. If approved for DME and other indications, analysts believe sales of Eylea could eventually hit $4 billion.

Looking ahead into fiscal 2014, Regeneron expects Eylea's U.S. sales to come in between $1.7 billion to $1.8 billion, representing year-over-year growth between 21% and 28%. In international markets (excluding Japan), Regeneron and Bayer share half of the profits and losses. In Japan, Regeneron receives a royalty on net sales. Overseas sales of Eylea came in at $472 million for 2013.

Eylea's fourth quarter revenue rose 47% to $610 million, while its full year revenue jumped 53% to $2.1 billion. The company's non-GAAP adjusted earnings per share rose 52% year-over-year to $2.24 per share, while its full-year non-GAAP adjusted earnings per share climbed 75% to $8.17 per share.

In other words, Regeneron is firing on all cylinders, and its partnership with Sanofi in alirocumab (cholesterol), sarilumab (rheumatoid arthritis), and other monoclonal antibodies could eventually yield blockbusters which would reduce the weight of Eylea on Regeneron's top line. Regeneron has rallied more than 80% over the past 12 months on optimism regarding Eylea sales and its shared pipeline with Sanofi, and its earnings suggest that the bullish trend could continue.

Will a new agreement with CVS Caremark boost sales of Arena's Belviq?
Arena and its partner Eisai announced yesterday that their obesity drug Belviq will reach more patients thanks to a new agreement with PBM (pharmacy benefits manager) CVS Caremark. The announcement caused shares of Arena to jump more than 7% yesterday, and that rally could continue today.

Arena and Eisai claim that the agreement will allow the drug to reach over half of all Americans. Sales of Arena's Belviq and its competitor, VIVUS' Qsymia, have both been painfully slow over the past year:

Source: Quarterly earnings reports. Note: Eisai markets Belviq globally, except in South Korea, Taiwan, Australia, New Zealand, and Israel.

Both companies have been giving away free samples to establish a patient base, but I believe that sales will remain in the single-digit millions for some time, a far cry from the blockbuster sales that some on Wall Street had expected. Investors should also note that health insurer Aetna is currently studying both Belviq and Qsymia in a pilot program which could also boost sales for both companies.

More good news for Omeros' OMS824
Last but not least, Omeros just announced additional positive phase 1 data for OMS824, its lead compound in the company's PDE10 (phosphodiesterase 10) program. OMS824 inhibits the production of PDE10, an enzyme implicated in brain diseases such as Huntington's disease and schizophrenia. If approved, analysts believe OMS824 could generate peak sales of $1 billion -- a huge boost for a company with no marketed products and only $1.4 million in revenues over the first nine months of fiscal 2013.

The phase 1 data shows a 70% engagement of PDE10 without evidence of extrapyramidal symptoms (EPS). An average of 66% occupancy at PDE10 was observed at the striatum, the part of the brain which plays a crucial role in cognition. The drug was reported to be "well tolerated" with the primary side effect being drowsiness.

Investors should note that this is the second bit of good news about OMS824 that Omeros has recently released. At the end of January, Omeros reported positive phase 2a results from a clinical trial of OMS824, which showed that the drug was well tolerated with limited side effects in a group of 33 patients.

OMS824 isn't Omeros' most advanced drug candidate. OMS302, a treatment for ophthalmological procedures, and OMS103HP, a treatment for arthroscopy and menisectomy procedures, are both closer to market approvals. Combined, the two drugs are expected to generate peak sales of just over $1 billion. Shares of Omeros have rallied more than 110% over the past 12 months on optimism regarding these three main drug candidates.