AstraZeneca's Epanova flunks key heart risk trial, giving Amarin's rival Vascepa a leg up

Hands forming heart
AstraZeneca's fish oil-derived Epanova failed to cut major cardiovascular events in a phase 3 study, leaving Amarin's Vascepa the only drug to boast such a benefit. (Pixabay)

As Amarin’s Vascepa recently became the first fish oil-derived drug approved by the FDA to cut heart risk among patients with high blood lipid levels, AstraZeneca was eager to show its Epanova could do the same. Now, that hope has died.

Monday, AstraZeneca said it will ditch a large-scale phase 3 trial of Epanova as an add-on to statins for lowering cardiovascular risks among patients with mixed dyslipidemia, a disease marked by elevated triglyceride levels.

It took that hit at the recommendation of an independent data monitoring committee, which determined that the study is unlikely to succeed. And it's an immediate financial blow; the company is taking a $100 million write-down on inventory and is reevaluating Epanova’s current asset value of $533 million.

“We are disappointed by these results, but we remain committed to addressing the needs of patients in the cardiovascular space where we have an extensive pipeline,” Mene Pangalos, AZ’s biopharmaceuticals R&D lead, said in a statement.

AstraZeneca got its hands on Epanova through its 2013 acquisition of Omthera Pharmaceuticals, which was then near an FDA decision for the omega-3 drug in patients with very high triglyceride levels, at or above 500 mg/dL.

Soon after that nod came through in 2014, AZ started the phase 3 outcomes trial, dubbed Strength, hoping to prove Epanova’s heart benefits against placebo in patients with high triglyceride levels—between 175 mg/dL and 499 mg/dL—but low HDL cholesterol, the so-called "good" kind. Now, after more than five years of testing involving 13,086 patients, that effort has turned into a dud.

RELATED: Amarin eyes blockbuster Vascepa sales as FDA grants heart-helping label expansion

Epanova is not yet launched, as all bets were put on Strength to reach a broader patient population. It might have had a chance at major revenues if the Strength trial succeeded; after all, Vascepa’s CV reduction label bears blockbuster sales projections. In a Monday memo to clients, Jefferies analyst Michael Yee noted that the Street’s consensus had previously pegged Epanova's peak sales at around $1 billion to $2 billion.

Prescription omega-3 fatty acids such as Vascepa, Epanova and GlaxoSmithKline’s Lovaza—versus over-the-counter fish oil food supplements—are FDA-approved to cut down triglyceride levels in the blood. But it wasn’t until Vascepa’s December 2019 label expansion that the class boasted a drug actually approved for lowering CV risks.

That approval was based on Amarin's Reduce-IT trial, where the drug showed it substantially cut major adverse CV events by 25% over about 4.9 years in statin takers with blood fat levels of 150 mg/dL or higher.

One major element differentiates Vascepa from the other drugs—it contains only purified EPA, whereas Epanova includes both EPA and DHA. Evidence has suggested that DHA may raise the level of bad LDL cholesterol, which is itself a risk factor for heart disease and stroke. So, it’s possible that DHA’s presence has compromised Epanova’s CV disease reduction ability.

AstraZeneca said it will present the full Strength data at an upcoming medical conference.

Editor's Note: The story was corrected to reflect that Epanova is not clinically available.