Source: Flickr user One Way Stock.

The stock market has witnessed an incredible resurgence over the past five years with the healthcare sector, especially biotech, leading the way.

It's not hard to understand why biotech stocks are back on investors' radars. Innovative drug pricing and demand is generally beyond the scope of whether or not the U.S. is doing well or doing poorly. In other words, people can't choose when they get sick. What this means is biotech companies often have excellent pricing power, consistent and/or growing demand for their products, and in recent years cheap access to cash with lending rates hanging around record lows. The end result has been a clear outperformance in biotech stocks compared to the S&P 500.

In spite of a good number of these biotech stocks seeing their share price double, triple, or perhaps vault even higher from their Great Recession lows, three high-growth stocks still stand out as particularly attractive buy candidates.

Gilead Sciences (NASDAQ:GILD)
I'm not sure any discussion about high-growth biotech stocks can be done without Gilead Sciences topping the list. Gilead's product portfolio includes some nice variety, but when all is said and done its growth comes down to three primary drugs: Harvoni, Sovaldi, and Stribild.

Sovaldi and Harvoni (a combination of Sovaldi and ledipasvir) are the company's revolutionary hepatitis C drugs that can be administered without the need for interferon, and in the case of Harvoni without the need for a ribavirin. The simplicity of dosing means better quality of life for hepatitis C sufferers, but it's the sustained virologic response that's often in excess of 90% that has patients and investors talking! Based on estimates from the Centers for Diseaase Control and Prevention of more than 3 million people in the U.S. having HCV, and the company treating 117,000 patients through the first three quarters of 2014, it leaves Gilead with a wide moat of patients yet to be reached.

Stribild is Gilead's next-generation four-in-one HIV-1 therapy designed to replace Atripla and Truvada. What's unique about Stribild is all four compounds were developed by Gilead. With Atripla, a three compound HIV drug, each component came from a different pharmaceutical company meaning Gilead had to share its net revenue three ways. Therefore, Stribild will allow Gilead to keep all of its total sales of the drug, ultimately boosting its profitability and margins.

Source: Gilead Sciences.

Prescription drug price trends also favor Gilead over the long term. Though Congress and pharmacy-benefit managers haven't been shy about their displeasure with Sovaldi's and Harvoni's $1,000 and $1,125 per-pill pricing, the nature of the industry and the unparalleled demand for pharmaceutical products in the U.S. should allow Gilead to retain its premier pricing.

With a forward P/E of just 10 and an estimated five-year growth rate in the 15%-20% range there's reason to believe Gilead's share price may still have substantial upside.

Jazz Pharmaceuticals (NASDAQ:JAZZ)
Ireland-based Jazz Pharmaceuticals might be up more than 2,000% over the trailing five-year period, but I suspect there could be even more room to run thanks to two key aspects.

First, Jazz's current product portfolio represents the perfect mix of high growth and specialized focused. For impressive growth Jazz has narcolepsy drug Xyrem to turn to. In the third quarter Xyrem sales rocketed higher by 33% to $204.3 million. Additionally, Defitelio, which Jazz acquired when it purchased Gentium, saw its net sales increase to $18.9 million from $13.1 million in the year-ago period.

Source: Jazz Pharmaceuticals.

Also insulating these high growth products is Erwinaze, a specialized cancer drug designed to treat acute lymphoblastic leukemia in patients that have an allergy to E.coli-derived asparaginase and pegaspargase chemotherapy drugs which are traditional used to treat ALL. Erwinaze's small patient pool allows Jazz to charge north of $150,000 for a full year's worth of treatment. All together Jazz's product portfolio should return average growth of nearly 20% over the next five years.

The second component that favors Jazz is its Dublin, Ireland address. Although Congress has instituted new rules which make tax inversions less appealing to current U.S. companies, Ireland's 12.5% corporate tax rate and Jazz's high-growth potential compounded with its diversified portfolio of products could make it attractive buyout bait.

At a forward P/E of just 17 I'd still suggest dialing up Jazz for your portfolio.

Lastly, even after a 400% run higher over the trailing five-year period, I believe Celgene deserves investors' attention.

Celgene's calling card to success is that it's on pace to double its revenue and triple its profits between 2013 and 2017 entirely through organic growth. Whereas most biotech stocks have turned toward acquisitions to drive growth, Celgene is instead focused on expanding its existing products to new indications. A good example would be cancer drug Revlimid which could see nearly a half-dozen new indications over the coming years. Otezla is also being tested in more than a half-dozen additional indications that should push this anti-inflammatory drug into blockbuster status.

Source: Celgene.

Another key point here is these label expansions help extend Celgene's already impressive patent exclusivity periods. Revlimid is on pace to be a $7 billion drug by 2017, but $2 billion of that growth is expected to come from new indications in the coming years. Further, Revlimid won't even begin seeing patent losses until 2019 at the earliest. This patent safety net provides investors with predictable growth and mountains of cash flow.

Celgene's forward P/E of 22 might not look appealing on the surface next to a Gilead at 10 or Jazz at around 17, but Celgene's projected growth rate of more than 20% arguably places Celgene PEG ratio at, or perhaps even below one, which is an excellent value for a growth stock.