Amarin is betting big on its fish-oil derivative Vascepa with a $400 million cash raise to boost its marketing ahead of an expected label expansion. A nod of approval from a U.S. cost watchdog could kick those hopes into overdrive.

Vascepa is cost-effective as an add-on to statins for patients with abnormally high triglyceride levels, compared with statins alone, according to a Wednesday draft report from the Institute for Clinical and Economic Review (ICER).

Vascepa’s blessing from ICER should help the drug make its case to payers and physicians as it awaits FDA approval for a new label showing it can reduce the risk of cardiovascular events.

In anticipation of the FDA’s Sept. 28 decision date, Amarin plans to double its salesforce to 800 by October and build inventory for a launch. And for cash to fuel that effort, Amarin announced a $400 million public offering last week. The sale could haul in up to $460 million if underwriters snap up all their allotted shares.

Investors were wary, though—particularly those who'd been hoping for a future buyout.

Earlier this year, one buyer reportedly showed interest in purchasing Amarin after the drugmaker’s landmark Reduce-It trial showed a 25% cardiovascular risk reduction in patients treated with Vascepa. But Amarin’s newest offering shows it's dedicated—at least in the short term—to building its own team rather than relying on that of a major drugmaker or going for a quick sellout.

After Amarin’s stock price closed down 17.8% last week at $18.08, shares opened at $18.48 in pre-market trading Wednesday on the heels of the ICER report.

The report also found that Johnson & Johnson's Xarelto, in addition to alcohol septal ablation, also met ICER’s cost-effectiveness standard—quality-adjusted life years gained. And with Vascepa already on the up-and-up, the ICER report could actually be of more use to J&J, which has seen cardiovascular med Xarelto slip in sales in recent years.

In the second quarter, Xarelto saw sales dip 19% stateside to $549 million with Medicare Part D’s "donut hole" provision severely knocking revenue. Despite that troubling trend, J&J Vice-Chairman Joaquin Duato said the drugmaker planned to even out Xarelto’s sales by growing the drug’s market share and volume in existing uses and focusing on launches in new indications.