3 Humongous Health-Care Stocks This Week: Celgene Corporation (CELG), Celldex Therapeutics, Inc. (CLDX)

The Dow set an all-time high, but it still was up only 2% for the week. If you want returns to really get excited about, look no further than the health-care sector. Here are three stocks that churned out humongous gains this week.

Mad money?
Shares in Astex Pharmaceuticals, Inc. (NASDAQ:ASTX) soared this week by nearly 37%. This was a huge jump considering there was no major news. So what happened?

The one significant event this week related to Astex was that TheStreet.com upgraded the stock from “hold” to “buy.” However, that upgrade occurred on Monday, while shares didn’t really take off until Wednesday. Once the buying frenzy started, it didn’t stop. The stock continued to climb strongly through the end of the week.

Celgene Corporation (NASDAQ:CELG)Trading volume for each of the last three days of the week was around four times higher than normal. It could be lots of smaller investors with mad money to spend. My guess, though, is that some entity with deep pockets is buying Astex like crazy. I won’t be surprised if we find out later that a hedge fund or other large investor scooped up big chunks of the stock.

Less loss equals big gain
There wasn’t much mystery behind the major moves for stem cell company Osiris Therapeutics, Inc. (NASDAQ:OSIR) . Shares surged nearly 35% for the week after the company posted better-than-expected earnings results.

Osiris reported a net loss of $0.08 per share, compared with a $0.15-per-share gain in the same quarter of the prior year. However, analysts were expecting the loss to be much worse at $0.15 per share. Osiris also reported $3.1 million in revenue, down from $11 million in the same quarter for 2011. The big year-over-year difference stemmed from Sanofi SA (ADR) (NYSE:SNY)‘s cancellation of an agreement in early 2012.

Look for revenue to pick up for Osiris now that the company has built a direct sales force for Grafix, its wound healing implant for diabetic foot ulcers and other serious wounds. Its sales team currently focuses on 10 major metropolitan areas. The company expects to double this direct sales force over the coming year.

Roller-coaster ride
Up, down, then back up gain. Celldex Therapeutics, Inc. (NASDAQ:CLDX) shareholders had to hold on tight, but their shares ended up on a high note, closing 20% higher for the week.

The stock eased higher earlier in the week as investors awaited the fourth-quarter earnings announcement before the market opened on Thursday. However, the results were disappointing, as Celldex Therapeutics, Inc. (NASDAQ:CLDX) missed analysts’ earnings estimates. Shares fell 17% — but only temporarily.By the end of the day, most of that loss was wiped out.

Friday was a different story. Celldex Therapeutics, Inc. (NASDAQ:CLDX) surged after investment firm Cantor raised its price target for the stock from $13 to $16 per share. Cantor’s rationale was that it now expects Celldex Therapeutics, Inc. (NASDAQ:CLDX) to see revenue from CDX-011 and rindopepimut in 2016 rather than 2017.

Pick of the week
Gains of 20% to 37% in one week are great. Unfortunately, they can also be fleeting. Which of the three winners from the past week is most likely to keep the positive momentum going? I’ll go with Astex.

The company does face the loss of orphan drug exclusivity for Dacogen in the U.S. in the next few months. However, I don’t think that will necessarily translate to slower sales. Celgene Corporation (NASDAQ:CELG) lost patent protection for rival drug Vidaza in 2011 yet continues to grow sales for the drug. Astex could see similar results.

I also think that Dacogen will see stronger European sales, potentially at Vidaza’s expense, after gaining approval for treating acute myeloid leukemia last September.

It was a humongous week. Perhaps the full year will turn out to be a humongous one for Astex as well.

The article 3 Humongous Health-Care Stocks This Week originally appeared on Fool.com and is written by Keith Speights.

Fool contributor Keith Speights and The Motley Fool have no position in any of the stocks mentioned.

Copyright © 1995 – 2013 The Motley Fool, LLC. All rights reserved. The Motley Fool has a disclosure policy.