Source: Amgen via Google Maps

Amgen's (AMGN -0.19%) stock price has climbed 23% in 2014. That's good enough to outpace the S&P 500, which has returned just shy of 9% and the company's Nasdaq biotechnology index peers, which have returned more than 17%.

Since Amgen is one of biotech's biggest companies, generating more than $18 billion in sales and nearly $6 billion dollars in annual profit, let's take a closer look at what's behind Amgen's market-beating stock price performance this year.

Targeting Goliath
Investors have 20 billion good reasons to be bidding shares in Amgen higher this year. That's the amount of money that statins raked in annually at their peak and the potential market opportunity that may await a new class of cholesterol lowering medication known as PCSK9 inhibitors.

This new generation of bad cholesterol busting medicine includes Amgen's evolocumab, a drug that posted an impressive track record during clinical trials and was submitted by Amgen to the FDA for approval in August.

The drug, which increases the number of bad cholesterol, or LDL, receptors in the liver, helped lower patients LDL counts by 57% during phase 3 studies. When combining evolocumab with statins, results were even better with LDL counts dropping 75%.

The August filing means that the FDA is expected to issue its decision on the drug next summer, clearing the way for Amgen to compete in what could prove to be a multibillion-dollar mega market.

Offsetting risk
The ability to usher new drugs like evolocumab to market takes some of the sting out of aging products in Amgen's portfolio, including Neupogen, Neulasta, and Epogen. Those drugs have lost, or will soon lose, patent protection, casting doubt on billions in Amgen annual sales.

Source: Amgen

However, before investors panic over risks to Amgen's top line, it's important to remember that those drugs are all biologics. That means that they're nearly impossible to duplicate. And despite the Affordable Care Act including language that should've cleared the way for the approval of biosimilars, regulators have been slow to develop rules that define a clear pathway to market.

Opportunity ripens
Even as Amgen's patent portfolio has gotten a reprieve, new drugs are making their way to market that could have shareholder-friendly consequences.

This summer, Amgen filed for FDA approval of Ivabradine, a drug that helps reduce cardiac death and hospitalizations in patients with heart failure. It's a big and important market. More than 5 million people are diagnosed with heart failure in the U.S. and about 50% of those diagnosed with heart failure die within five years. Despite the Ivabradine filing being for use as a second line therapy behind beta blockers, the drug marks an intriguing foray into cardiac care for Amgen.

Amgen also filed for approval of T-Vec, a drug that is injected into tumors to spark the immune system to battle melanoma, this past summer. Melanoma is one of the most difficult-to- treat cancers and if T-Vec wins approval, it could see significant sales given that late stage melanoma patients have limited treatment options.

Fool-worthy final thoughts
Amgen has a lot of opportunity to replace long-in-the tooth products with a new wave of intriguing therapies, but evolocumab is the most exciting. The American Heart Association, or AHA, estimates spending on cardiovascular disease in the U.S. will triple by 2030 to more than $800 billion as the number of people with the disease grows to roughly 40% of the population.

A lot of that spending will be focused on treating seniors. That's because the AHA adjusted its treatment guidelines late last year in a move that increases the addressable patient population among those over 60 years of age from 30% to 80%. As a result, aging baby boomers could turn PCSK9 drugs like evolocumab into multibillion-dollar blockbusters. But even if evolocumab falls short, Amgen's sales could still grow thanks to other therapies, like T-Vec.