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While the stock market in general has been sold off over the last few months, healthcare-related stocks have fallen much harder than the rest of the market. The Vanguard Health Care ETF (NYSEMKT:VHT), for example, is down more than 12% from its summertime highs, while the S&P 500 is down a much more modest 4% over the same time frame, which could make now a great time for investors to go bargain hunting for the best companies in the healthcare universe.

We asked our team of Motley Fool contributors to highlight blue-chip biotech stocks they think are great companies to consider owning for the long haul that are currently trading for mouth-watering prices. Read below to see what they had to say!

George Budwell: Celgene Corp. (NASDAQ:CELG) is a 35-year-old biotech company that has grown into a leader in the fight against hematological malignancies and is now rapidly becoming a key player in the world of inflammatory diseases, especially after its recent acquisition of Receptos. 

Right off the bat, I could cite Celgene's 22.1% CAGR over the last five years for its total revenues, or Wall Street's projected 13.7% CAGR for the next five, as great reasons to like this blue-chip biotech stock. After all, these double-digit growth figures demonstrate that Celgene's top line is in stellar shape, reflecting the strength of its core product portfolio consisting of the cancer drugs Revlimid and Abraxane, and the relative newcomer, the psoriatic arthritis and psoriasis medicine Otezla. 

But the real reason I think this is a great biotech to own for the long term is the exciting possibilities emanating from the company's partnership agreements with AstraZeneca and Juno Therapeutics in the red-hot area of immuno-oncology.

Taken together, these two key research partnerships have the potential to deepen Celgene's already-dominant position in the area of blood-based cancers -- a market that was valued at $24 billion in 2014 and is expected to grow to around $29 billion by 2017.

Although nothing is a given in the world of experimental cancer drugs, I think these two particular collaborations are noteworthy because they are exploring the use of the potent checkpoint inhibitors and transformative T-cell therapies to battle a wide diversity of hematological malignancies. As such, they both have the ability to open up significant new revenue sources for Celgene and its partners within the next 4 to 5 years.

Todd Campbell: One of big biotech's biggest falls from grace has occurred in Biogen (NASDAQ:BIIB), a biotech Goliath and market share leader in the treatment of multiple sclerosis. Following news this summer that growth of its multibillion-dollar drug Tecfidera was slowing, and that a patient had passed away from a rare brain disease, shares have fallen by roughly 36%.

Although safety is always a major concern for any biotech investors, investors should know that cases of this rare brain disease aren't uncommon among various MS treatments. For example, Biogen's Tysabri was temporarily removed from the market back in 2005 after three cases occurred, but following its reintroduction, Tysabri still went on to become a top-selling medication, with $2 billion in annual sales.

Assuming Biogen can help doctors evaluate which patients are more likely than others to develop this disease -- something it's been successful at doing with Tysabri -- then I believe Tecfidera will remain a leader among the current class of oral MS therapies. If so, investors might want to consider buying Biogen shares because after the sell-off, investors are paying just 14.6 times forward EPS for shares, and just 1.03 times expected five-year earnings growth (PEG ratio), and that hardly seems rich for a company with Biogen's biotech chops.

Brian Feroldi: There are plenty of great choices for healthcare-focused investors to consider right now, but one company in particular that I think is an exceptional value at the moment is Amgen (NASDAQ:AMGN).

While Amgen may be facing some challenges in the coming years from the recent approval of biosimiliars, the company has been very successful at producing new drugs that should help it continue to grow revenue, even if its legacy products begin to decline. Prolia and Kyprolis, for example, are already growing nicely for the company, and it has scored several major regulatory approvals for drugs that could be blockbusters like cholesterol-lowering drug Repatha, chronic heart failure treatment Corlanor, and leukemia treatment Blincyto.

Between cost reductions, new drug launches, and share repurchases, Wall Street believes Amgen can grow its earnings by a healthy 12% on average over the next five years. Add in the company's fast-growing dividend, which currently yields over 2%, and I think the company has market-beating potential.

Roughly a month ago, I made the argument that Amgen was cheap, and its price hasn't budged much since. Opportunistic investors may want to try to take advantage of that fact.