Editor’s note: A previous version of this article incorrectly stated Exelixis' earnings report date; the company will report earnings on Feb. 21. The Fool regrets the error.

With no major health-care conferences on the docket this week, and the Food and Drug Administration ruling two days early on Celgene's multiple myeloma drug, Pomalyst, this week's main focus is earnings, earnings, and more earnings. Just as we did last week, we have four big names reporting, and you'd be small-"f" foolish to miss out on any of them.

On Tuesday, we'll hear from Seattle Genetics (NASDAQ:SGEN), developer of antibody-drug conjugates that deliver chemotherapy toxins directly to tumors. Investors will definitely be looking for an improvement in sales from Adcetris, the company's only FDA-approved drug designed to be a second-line treatment of Hodgkin's lymphoma. I will be ignoring most of the Adcetris data and focusing on what upcoming data Seattle Genetics has in store. With its $3.6 billion market value, what I can say for certain is that its loss had better not be much higher (if at all) from the $0.11 per share currently forecast. 

Health-benefit solutions provider WellCare Health Plans (NYSE:WCG) steps up to the plate on Wednesday and should offer an interesting report from a value investors' perspective, as it's been the laggard of the group. The Affordable Care Act is expected to cap insurers' earnings and disallow them from turning away patients with pre-existing conditions, but it also will bring millions of newly insured Americans into the fold. I suspect thast WellCare's guidance will be in-line with, if not higher than, what's currently projected on Wall Street as investors underestimate the cost-cutting ability of the health-benefits sector.

Finally, Thursday will bring the two most important reports of the week from the biotech sector: Alexion Pharmaceuticals (NASDAQ:ALXN) and Regeneron Pharmaceuticals (NASDAQ:REGN).

Alexion, maker of Soliris, the most expensive drug in the world, is expected to report a profit of $0.53 on 39% sales growth to $316.5 million. While an earnings beat appears all but in the cards given its average beat of 22.7% over the previous four quarters, I'm concerned with how intricately tied to Soliris Alexion's pipeline has become. If Soliris is unable to gain additional indications, or physicians run into reimbursement problems with the spendy drug, then its price-to-sales ratio of 17 will come crashing down like a ton of bricks.

Regeneron, on the other hand, will be looking to keep the good times rolling with its wet age-related macular degeneration wonder drug, Eylea. Sales in the upcoming quarter are expected to jump 219% with earnings of $1.11 per share, reversing a year-ago loss of $0.54. Considering that Regeneron and Sanofi also gained EU approval for Zaltrap as a second-line treatment for metastatic colorectal cancer just last week, I'll be looking for Regeneron to once again be boosting its guidance.