The market might have had an abbreviated week with the Dr. Martin Luther King Jr. holiday, but we have no shortage of big gainers in the health-care sector. Here are three of the most humongous health-care stocks for the past week.

Finding the way to an acquisition
Topping our list is MAP Pharmaceuticals (NASDAQ: MAPP). Shares soared by 59% for the week after Allergan (NYSE: AGN) announced plans to acquire the company.

The big prize for Allergan is MAP's migraine drug, Levadex. MAP originally submitted a New Drug Application, or NDA, for Levadex to the Food and Drug Administration in May 2011. However, the company needed to provide additional information and resubmitted the NDA in Oct. 2012. The FDA is scheduled to make a decision on April 15 of this year.

Allergan's due diligence for the $959 million acquisition was probably not too difficult. The two companies were already working closely with each other after signing an agreement to co-promote Levadex back in early 2011. 

Winning while waiting
Keryx Biopharmaceuticals (KERX) shares were up 18% this week as investors eagerly await results from the company's phase 3 trial of Zerenex. Those results were initially expected to be announced by the end of 2012, but that didn't happen. According to Keryx a couple of weeks ago, phase 3 results "are expected to be announced imminently."

If the results are positive, Keryx should move quickly to file an NDA in the U.S. The company's partner, Japan Tobacco and Torii Pharmaceutical, already submitted for approval in Japan based on good results from phase 3 studies conducted there. In those studies, Zerenex was found to be effective and safe in treating elevated phosphate levels experienced by patients with end-stage renal disease, or ESRD.

Assuming the company does ultimately gain FDA approval for the Zerenex, it could take advantage of a gift provided by Congress in the recent fiscal cliff deal. The legislation pushed back inclusion of ESRD drugs in payment bundling until 2016. That delay could help Keryx in marketing Zerenex in the U.S. during its presumed commercial launch.

Domo arigato, Mr. Roboto
Styxx, the popular rock group in the '70s and '80s, taught people how to say "thank you" in Japanese with their hit song "Mr. Roboto." And that's exactly what shareholders of robotic surgical systems maker Intuitive Surgical (ISRG 2.21%) should be saying after the company reported terrific earnings. Shares rose nearly 14% this week.

Earnings for the last quarter were $4.25 per share, handily beating analyst estimates of $4.03. Those earnings also came on strong revenue growth of 23% year over year. According to the company, the solid numbers stemmed from both higher sales of its da Vinci surgical systems and increasing use of the systems with more types of procedures.

Shares took a hit in December after short-selling firm Citron Research targeted Intuitive Surgical, questioning whether the company could continue its phenomenal growth. I think Intuitive Surgical has now pretty clearly shown that it can.

Top pick
My top pick from our humongous list this week is Intuitive Surgical. I think this stock is in a good position to have investors singing another Styxx song: "The Best of Times."