I'm going to have to wait to see if my prediction that the Food and Drug Administration will reject Amarin's (AMRN 1.17%) appeal of the FDA's decision to rescind the special protocol assessment, or SPA, for the company's triglyceride-lowering drug, Vascepa.

The FDA isn't even willing yet to look at the appeal.

The disclosure in the 8-K report filed with the SEC is a little opaque, but it appears the FDA told Amarin that it wasn't willing to consider the appeal because it's part of Amarin's application to expand the indication for Vascepa to include patients with moderately high triglyceride levels.

The FDA hasn't turned down the expanded marketing application yet -- it's scheduled to make a decision by Dec. 20 if it sticks to its internal schedule -- so the agency argues there's no point in looking at the appeal. Yet.

Amarin has asked for a meeting with people higher on the totem pole, but the meeting wasn't granted.

A half-hearted deal
A special protocol assessment is an agreement between a company and the FDA under which, if the company does everything that's asked and the data turns out as expected, the agency will approve the drug. The FDA, though, is not required to OK the drug if the situation changes.

The SPA was put in place before Amarin ran its clinical trial in patients with moderately high triglyceride levels. The FDA agreed to accept a drop in triglyceride levels as a surrogate endpoint as long as Amarin had an outcomes study -- measuring heart attacks, strokes, and the like -- that was substantially enrolled.

Amarin held up its half of the bargain. Vascepa reduced triglycerides by a placebo-adjusted 21.5% at the higher dose. And the company has reached the agreed-upon level of enrollment in its outcomes study.

But the FDA always has the ability to rescind the SPA if new data becomes available, and it took that option, arguing that trials completed since the protocol was put in place have shown that drugs can lower triglyceride levels without improving cardiovascular outcomes.

For example, in the ACCORD-Lipid trial, patients were given AbbVie's (ABBV -4.82%) Tricor, which lowered triglyceride levels but didn't have an effect on adverse cardiovascular events. Merck's (MRK 0.36%) had a similar experience with Cordaptive, which improves triglyceride and cholesterol levels but failed to improve outcomes.

Rejection coming
It seems inevitable at this point. Then again, I thought that was pretty clear after the advisory committee agreed with the FDA that outcomes data should be available before approval.

I'm a little surprised that Amarin stock is down 11% today -- the appeal was a Hail Mary -- but it's still up substantially for the week, so clearly investors are still trying to figure out how much the biotech is worth without the expanded indication.

Vascepa will remain on the market for patients with extremely high triglyceride levels. In theory, the drug could be used off label like GlaxoSmithKline's (GSK 0.76%) Lovaza in patients with moderately high levels, but Amarin hasn't been able to break into that market; GlaxoSmithKline sold $208 million worth of Lovaza in the third quarter, compared to Amarin's $8.4 million worth of Vascepa.

Having the drug approved for the less severe patients was supposed to help Amarin take market share from GlaxoSmithKline, but now it appears Amarin will have to wait until the outcomes trial concludes in a few years.

That's plenty of time to file multiple appeals that are all likely to be rejected.