(Fortune Magazine) -- Fow-fat pigs and chickens: Those were Amgen's initial research interests. By 1991, the first year the biotech company made the Fastest-Growing list, it had shifted its focus to humans and launched two soon-to-be blockbusters, Epogen for anemia (1989) and Neupogen for chemotherapy patients (1991).

But drug development is risky, expensive, and often disappointing. After making the list in four consecutive years, Amgen (Charts) lost some of its momentum. The pipeline was starting to run dry -- always worrisome for a biotech company. Today, though, the 26-year-old firm is prospering. Continued sales from its stable of anemia- and cancer-fighting drugs helped push its profits up 55% last year, to $3.7 billion. And for the past 20 years the company has recorded average annual sales growth of 37%.

After taking over in 2000, CEO Kevin Sharer increased investment in R&D, reshaped the company's management structure, and orchestrated several acquisitions that allowed Amgen to compete with big pharmaceutical companies. Under Sharer, an aeronautical engineer who served on two nuclear submarines and honed his management skills at GE, Amgen's stock has outperformed the S&P 500 and the Amex pharmaceutical index.

While Amgen, like other pharma companies, faces a future of long and difficult product cycles and increased competition from generics, the company forecasts earnings growth upwards of 17% in 2006. It's betting on a new colon-cancer drug, which is awaiting FDA approval, and 46 other drugs currently in trials to carry the company, patients, and shareholders into the future.

At a Glance

Headquarters

Thousand Oaks, Calif.

CEO

Kevin Sharer

Sales

$12.4 billion

Market value

$77 billion

Employees

20,000