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When the stock market swoons, we Fools tend to go on a shopping spree and try to buy positions in our favorite names that are suddenly trading at a discount. We asked our team of Motley Fool contributors to share their favorite blue-chip biotechs that the market has generously thrown in the discount pile.

So, which of these biotech big boys do we think deserves a prime spot on your radar? Read below to find out why we think it's a great time for investors to take a closer look at Gilead Sciences (GILD 0.91%), Celgene (CELG), Biogen (BIIB 2.03%), and Amgen (AMGN 2.35%).

Todd CampbellIf you're staring at a list of tumbling biotech stocks, wondering if there are any top-tier leaders on sale, then you may want to take a closer look at Celgene, because Celgene might be the best of a bumper crop of biotechs that can be bought on the cheap. 

Celgene's rock-solid balance sheet includes $7.5 billion in cash and short-term investments, a slate of top-selling drugs, including the $5.6 billion per year multiple myeloma drug Revlimid, and a host of up-and-coming therapies that could move the needle, including a promising oral MS drug it recently acquired.

Additionally, Celgene holds favor as being one of the few companies out there willing to provide investors with a long-term forecast that stretches out to 2020. Celgene believes increasing sales for Revlimid, its cancer drug Abraxane, and psoriasis drug Otezla, could lead to revenue that eclipses $21 billion that year. Importantly, if Celgene can hit that revenue target, then management thinks its EPS could total at least $13. If we put a 20 multiple on that estimate, we get a 2020 price target of $260, up a whopping 125% from current levels. Of course, no one knows where Celgene's shares may be heading, but with that kind of an outlook, it's the company I'm focusing on. 

Brian Feroldi: For investors who have yet to dip their toe in the biotech pool, it can be a smart idea to start with names that offer the investors a good combination of growth, value, and even a little bit of income. If that sounds like an impossible combination to achieve in the crazy world of biotech, then let me introduce you to Gilead Sciences, one of the strongest names in the sector.

Gilead has been a dream stock for years thanks largely to the company's strong position in treating HIV/AIDS, where it offers a number of best-selling drugs. However, Gilead recently entered the hepatitis C market with the launch of two drugs, Sovaldi and Harvoni, that have each been absolute home runs. Largely driven by the success of those two drugs, Gilead rang up more than $8.2 billion of revenue in the second quarter of this year alone, up a huge 26% over the year-ago period. Better yet, management just raised its guidance again, and the company now expects 2015 revenue to be north of $29 billion.

Beyond its drugs that are currently cranking out cash, Gilead boasts a pipeline full of potential. The company has 10 new compounds that are either pending regulatory approval or already in phase 3 clinical trials, and several of these drugs could push the company into new areas of research like hematology/oncology and cardiovascular disease. While it's unlikely that all of these compounds will work out as planned, the company does have a strong history of success on its side that should give investors confidence that it knows what it's doing.

In the meantime, Gilead is returning gobs of cash cash to investors through a massive $15 billion share repurchase program, as well as with a recently-authorized dividend payment that currently yields about 1.6%. Despite all of this goodness, the company is only trading at about nine times 2016 earnings estimates, which is a price even value investors can get behind. 

For any investor that has been considering buying into their first biotech, I think Gilead is a great choice.

Cheryl SwansonBiogen's share price plunged 22% even before the current market turbulence, after the company slashed its 2015 revenue and profit forecasts. As a Biogen investor, I'm taking the slump in stride since I believe this company's pipeline offers far more than the market is seeing. 

Let's start with anti-LINGO, a drug that could actually reverse nerve damage in multiple sclerosis patients. The phase 2 trial in MS is due to read out next year, and Credit Suisse has pegged the peak market for this drug at a whopping $10 billion. In addition, while Biogen's Alzheimer's drug aducanumab has a risky and expensive phase 3 trial ahead, if this drug succeeds, it should spur massive upside for this stock.  

Meanwhile, Biogen absolutely dominates the $20 billion global MS market and has yet another MS drug (Zinbreyta) pending U.S. and EU approvals. While Tecfidera, Biogen's big growth engine, missed its mark last quarter -- creating the kind of nasty surprise Wall Street analysts hate -- it's still the top-selling oral MS drug. 

If Biogen's stock price lingers in the doldrums, I wouldn't be surprised to see the drug developer become a takeover target thanks to its high-margin business and pipeline. On the other hand, Biogen could also make an exciting move to acquire a new company, or even a blockbuster asset, such as it did when it bought out Tysabri rights from Elan. 

While it seems to be that Biogen is the most unloved of the four biotech blue chips, the company recently announced a $5 billion share repurchase program. That should bring down the share count and perhaps help put a floor under the share price. While I'm not expecting a fast return on this stock, I'm still a fan.  

George Budwell: Amgen is one of my personal favorite blue-chip biotechs right now because the stock offers both solid growth prospects, as well as a rock-solid dividend payment. So, after last month's nearly 14% dip in Amgen's share price, I'm strongly considering adding this stock to my portfolio. 

My growing interest in the stock boils down to three main issues. Firstly, Amgen is experiencing extremely strong sales growth among products such as Enbrel, Prolia, Sensipar, Kyprolis, and XGEVA, helping it to offset the negative impacts of a strong dollar and falling sales for former top sellers like the blockbuster white-blood-cell booster Neupogen. 

Next, Amgen's top notch clinical pipeline has recently led to three major regulatory approvals in the cholesterol-lowering drug Repatha, the leukemia drug Blincyto, and the chronic heart failure treatment Corlanor. This infusion of brand-new medicines with blockbuster potential is expected to lead to approximately a 10% rise in 2016 earnings for the biotech, giving the stock a reasonable forward price to earnings ratio of 14 at current levels. 

The final reason Amgen looks like a compelling buy to me is its dividend. Although its present yield of roughly 2% is slightly lower than the sector average of around 2.2%, Amgen's trailing-12-month payout ratio is a mere 24%, well below the sector's median of approximately 35%. The biotech's dividend thus appears safe for the long term.

All told, Amgen is a dividend-paying biotech that should see double-digit growth on its top and bottom lines in the years to come, making it worth a deeper look by investors looking for a safe haven in this turbulent market.