Amarin's (NASDAQ:AMRN) Vascepa is the only fish oil supplement approved by the FDA to treat anything, and sales have been soaring since the company presented evidence that it can prevent heart attacks for millions of high-risk patients. On Tuesday, the company announced preliminary 2019 results, and as expected, Vascepa sales growth was impressive.

In 2019, Vascepa sales grew around 85% compared to 2018, coming in between $410 million and $425 million. And the company thinks 2020 will be much better. That's a fairly simple prediction to make because, in December, the Food and Drug Administration approved Vascepa to prevent patients at risk of a second heart attack from having one. 

Person with a lab coat looking at test tubes.

Image source: Getty Images.

Big expectations

The company projects 2020 sales will reach between $650 million and $700 million, and most analysts that follow Amarin will be surprised if the company doesn't raise this expectation at least a couple of times in 2020. While Vascepa's been expanded to treat a very well defined patient population, there are still millions who fit the description.

Amarin isn't relying entirely on the FDA's label expansion to drive sales growth. The company's human resources department is extra-busy onboarding enough salespeople to double its U.S. footprint to 800 this year.

Tipping the scales

Rapidly hiring more sales representatives isn't cheap, and in the first half of 2020, Amarin expects operating expenses will exceed gross revenue available to pay them by a reasonable amount.

Amarin finished 2019 with around $645 million in cash and despite feeling some growing pains at the moment, this figure will probably rise before the end of 2020. Once the company's new sales reps get settled in, the company thinks it can achieve positive cash flows with annual top-line revenue of around $600 million.