Source: Flickr user UCI Institute for Innovation.

The cardiovascular drug market has undergone quite a bit of flux during this decade as blockbuster therapies like cholesterol-lowering drug Lipitor, the best-selling drug of all-time, lost patent protection and were exposed to generic competition. Yet, even with dominant brand-name therapies seeing their sales erode due to generic competitors, the top 20 global cardiovascular drug developers generated $54.4 billion in sales in 2014. This is a disease indication with a load of potential and a sizable patient pool.

According to the Centers for Disease Control and Prevention, some 26.6 million adults, or more than 11% of the adult population in the U.S., have been diagnosed with heart disease. Furthermore, 73.5 million adults have what are considered to be high low-density lipoprotein, or LDL-cholesterol, levels. That's nearly one in three Americans that could benefit from cardiovascular therapies to help control their high LDL-C levels before they become troublesome.

The world's largest cardiovascular drugmakers are names you'd likely recognize. U.K.-based AstraZeneca, Sanofi, and Merck were the kingpins of the sector in 2014 with sales of $7.7. billion, $6.6 billion, and $5.2 billion according to data provided by GlobalData. However, one new company is set to enter the cardiovascular drug industry, and it could, by the end of the decade, potentially find itself among the top three cardiovascular drug developers in terms of sales.

Can you guess the identity of this soon-to-be cardiovascular giant?
If you're willing to take a guess at the name of this company, I'll give you a moment.

Got your answer?

I'm not one for leaving readers in suspense, so if you said biotech giant Amgen (NASDAQ:AMGN), then give yourself a pat on the back.

Amgen's move into cardiovascular is a bit odd, because large-cap biotech and Big Pharma stocks typically stick to the two to five indications they dominate in. It can often be a very costly venture to enter a new disease indication, or to take on established leaders within an indication. Nonetheless, Amgen appears ready to make its mark on cardiovascular care with a trio of drugs (two of which have already been approved by the Food and Drug Administration).

Source: Amgen.

First Corlanor
Amgen's first FDA approval came this April for Corlanor as a treatment designed to reduce hospitalizations from worsening heart failure. Patients that suffer from chronic heart failure typically have from a faster heartbeat. Corlanor helps adjust the heart's natural pacemaker to a normal rhythm. In the SHIFT study Corlanor led to a 26% relative risk reduction in the risk of hospitalization for worsening heart failure, and an 18% relative risk reduction for risk of hospitalization or cardiovascular death for worsening heart failure.

Additionally, chronic heart failure caused by weakness in the lower-left portion of the heart can extend for years, meaning Corlanor could be a therapy taken for an extended duration by patients. Wall Street anticipates Corlanor could have a peak sales potential of $500 million, but I believe it may be underestimating the drug's potential.  

Then Repatha
Next up is Repatha, an injectable LDL-cholesterol lowering therapy approved by the FDA in late August to treat patients with heterozygous familial hypercholesterolemia, homozygous familial hypercholesterolemia, and patients with clinical atherosclerotic cardiovascular disease who aren't seeing enough of an LDL-cholesterol reduction with statin therapy alone.


Source: Amgen.

Repatha is part of a new class of drugs known as PCSK9 inhibitors that work by targeting the PCSK9 protein and inhibiting its ability to bind with receptors located on the liver. These receptors are important for filtering LDL-cholesterol (the bad kind) out of the body. If these receptors are bound by PCSK9, they fail to rid the body of LDL-C and the patient can suffer the potentially dangerous side effects of elevated cholesterol levels.

In the early going Repatha's indications will be relatively restrictive -- just HoFH, HeFH, and high-risk cardiovascular patients that have a history of non-fatal heart attacks and strokes. However, looking further down the road, it's quite possible Repatha could see its indications expand to a larger swath of the population. In clinical trials, Repatha led to an average LDL-C reduction of around 60%, so it's possible it could offer meaningful improvement for patients that aren't considered high risk. Of course, only time will tell if the FDA agrees.

Peak sales estimates for Repatha vary widlly and range from as low as $2 billion to as much as $5 billion depending on its label expansion.

Now TA-8995
Finally, it may have flown under the radar of some investors, but Amgen announced on Sept. 16 that it was acquiring privately held, Netherlands-based drug developer Dezima for $300 million plus potential incentives worth as much as $1.25 billion.

Source: Centers for Disease Control and Prevention.

The "heart" and soul of Dezima's pipeline is TA-8995, an oral, once-daily CETP inhibitor that's being targeted as a treatment for dyslipidemia, which by definition is an abnormal levels of lipids in the blood. In its Phase 2b trial known as TULIP, TA-8995 reduced LDL-cholesterol levels by 45% to 48% relative to the baseline; and most importantly, the LDL-C reduction was consistent regardless of whether it was administered in conjunction with statins or as a monotherapy. High-density lipoprotein levels, or the good type of cholesterol, rose by a remarkable 161%.

Consider Amgen's purchase of Dezima as a smart way of hedging its bet on Repatha in case it's unable to expand its patient pool much beyond its current label. Phase 3 studies of TA-8995 are expected to begin in the first half of 2016, and if approved the drug could certainly have blockbuster potential.

Tying things together
Investors should understand that there are a lot of what-ifs built into the aforementioned peak sales estimates, including variables such as competition, drug launch success, and the ability to boost pricing if need be. However, if Amgen is able to hit on all cylinders in cardiovascular, it could be looking at peak annual sales of anywhere from $3 billion on the low-end to perhaps as high as $6 billion, with a lot depending on Repatha's potential label expansion.

Based on the $20.1 billion in sales Amgen recorded in 2014, I'd suggest its cardiovascular portfolio has a genuine opportunity to represent as much as 20% of its total sales by the end of the decade, as well as push its way into the top five, or perhaps even three, cardiovascular drug developers by sales around the world by 2020.

If you needed yet another reason to get Amgen on your watchlist, consider these three cardiovascular products to be that impetus.

Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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