When graying baby boomers celebrate the 40th anniversary of Woodstock in August, many of them will be popping cholesterol-lowering pills and blood pressure medication instead of the harder stuff of their youth.

And as boomers age, the British drug giant AstraZeneca will keep taking a bigger share of their outlays for anti-cholesterol drugs and other meds that treat the ailments that come with aging.

The reason: Direct competitors such as Merck and Pfizer are getting hammered by patent expirations, which invite competition from generic drugs. AstraZeneca has a stable of popular drugs with years of patent protection remaining.

Merck sales, for example, fell 5% in the first quarter, due largely to the patent loss on its osteoporosis drug Fosamax. And Pfizer sales declined by 3% because of generic competition and falling sales of its cholesterol-lowering drug, Lipitor, which was losing share to Crestor, made by -- you guessed it -- AstraZeneca. Crestor's 35% sales growth helped AstraZeneca beat most of its U.S. rivals with a 7% sales growth in the first quarter. AstraZeneca's top-selling drugs also include Nexium, used to treat ulcers, and Arimidex and Symbicort, which treat cancer and breathing problems, respectively.

The British drug giant also stands above its peers because it has a "hefty" pipeline of drugs in late-stage development, Morningstar analyst Damien Conover says. While competitors like Eli Lilly face serious challenges over the next four years as so many of their drugs go off patent, AstraZeneca has several potential blockbusters coming on line, Conover says. They include one, Dapagliflozin, to treat diabetes and several new cancer therapies.

Rival Bristol-Myers Squibb also has an impressive portfolio of drugs, a strong pipeline and solid sales growth. But AstraZeneca's stock has held up much better over the past two years, probably because the British company performs much better by so many measures, including cash flow, operating margins, and return on assets and equity. So we'll give the nod to AstraZeneca as the likely winner among the Big Pharma companies.

Continued: Genzyme: An inventive leader