What happened

A good day for a biotech is when one of its products wins regulatory authorization or approval. That was the case on Tuesday with Amarin (AMRN -18.94%), which announced that its sole commercialized drug had gotten the green light from a regulator across the Pacific Ocean. As a result, the company's share price crept up by almost 1%, more or less in line with the S&P 500 index's gain on the day.

So what

Before market open, Amarin announced that its Vazkepa (brand-named Vascepa in the U.S.) has been approved by Australia's Therapeutic Good Administration (TGA). The catch is that the approval is somewhat limited, as it covers only statin-treated adult patients with elevated triglycerides, which have demonstrated high risk of cardiovascular afflictions.

Additionally, the biotech has been granted patents guaranteeing market exclusivity for Vazkepa "into the early 2030s." It did not get more specific.

Amarin didn't hesitate to mention that the Australian nod represents the fifth regulatory approval for Vazkepa/Vascepa. Among these jurisdictions are the U.S. and the European Union, which consists of 27 countries on that continent.

In the press release heralding the TGA's move, Amarin quoted Chief Scientific Officer Steven Ketchum as saying that it

marks important progress for patients in that country with unmet need to address residual cardiovascular risk as well as for Amarin's efforts to expand access to Vazkepa across global markets.

Now what

While large, Australia isn't all that populous. It's home to 26 million people, compared to nearly 451 million in the European Union and 337 million-plus in the U.S. That, combined with the limited scope of the TGA's approval, tempered the good news. Still, it's certainly a win for Amarin, and investors were right to celebrate the victory.