Court Affirms Ban on Opana ER Generic in Win for Endo

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May 4 — Endo International Plc said May 2 that a federal court ruled in its favor in patent infringement litigation related to generic versions of its top-selling painkiller Opana ER.

Judge Thomas P. Griesa of the U.S. District Court for the Southern District of New York April 29 affirmed the court's earlier ruling, blocking generic versions of Opana ER (oxymorphone hydrochloride extended-release). Versions include one marketed by Actavis Inc., the U.S. generics business of Allergan Plc, and an additional generic product from Roxane Laboratories, until 2023.

The ruling means that neither Actavis, the U.S. generics business of Allergan Plc or Roxane Laboratories Inc. will be able to sell generic versions of noncrush-resistant Opana ER until the patents covering the product expire. The Food and Drug Administration has approved Roxane's generic, but the product isn't yet on the market.

Emergency Motion

Meanwhile, on May 3, Actavis filed an emergency motion for a stay pending appeal at the U.S. Court of Appeals for the Federal Circuit. It's seeking a fast-track briefing schedule for the case.

Bloomberg BNA contacted company representatives at Endo, Actavis and Roxane (now part of West-Ward Pharmaceuticals Corp.) but they didn't immediately respond to phone requests for comment on the ruling.

Opana ER is an opioid agonist indicated for the relief of moderate to severe pain in patients requiring continuous opioid treatment for an extended period.

Endo received approval from the FDA for a reformulated, crush-resistant version of Opana ER in 2011 (09 PLIR 1564, 12/16/11). The reformulated Opana ER was designed to be more difficult to abuse and misuse. Endo voluntarily withdrew the original formula of Opana ER from sale in 2012 and now only markets the reformulated, crush-resistant version.

Falling Sales

Endo has seen sales of Opana ER fall due to competition from noncrush-resistant generic versions. In a securities filing last year, Endo said Opana sales continued “to be impacted by competing generic versions.”

Generic copies of Opana ER now account for almost 47 percent of weekly extended-release oxymorphone prescriptions in the U.S., Bloomberg Intelligence analyst Aude Gerspacher said. Actavis's version makes up 11.7 percent of the generic market while a licensed authorized generic version marketed by Impax Laboratories Inc. accounts for 35 percent, Gerspacher said.

And if Actavis pulls its noncrush-resistant generic version off the market to comply with the court order, it's Impax Laboratories Inc., not Endo, that is likely to reap the financial benefits, Gerspacher said.

Impax to Benefit?

Impax makes the only other noncrush-resistant version of Opana ER currently on the market, an authorized generic version that it started marketing in January 2013. Endo granted Impax a license to make the authorized generic as part of a patent litigation settlement. That settlement is the currently at the heart of both government and private payer antitrust lawsuits that allege the authorized generic deal violates antitrust laws (14 PLIR 469, 4/1/16).

Prior Ruling Upheld

Judge Griesa upheld his earlier decision from August 2015 in which he ruled, following an extensive bench trial, that Actavis and Roxane infringed Endo's U.S. Patent Nos. 8,309,122 (“the ’122 Patent”) and 8,329,216 (“the ’216 Patent”) (13 PLIR 1204, 8/21/15), and enjoined them from selling generic versions of Opana ER.

According to the FDA's Orange Book, the ’122 and ’216 patents, which cover oxymorphone controlled-release formulations, expire Feb. 4, 2023. The Orange Book, officially titled “Approved Drug Products with Therapeutic Equivalence Evaluations,” lists patents that brand-name companies claim cover their drug products.

Harms to Endo Cited

Griesa said the injunction against Actavis's marketing of its generic and any future generic launch by Roxane was justified because of the harms to Endo.

Actavis launched its generic version of Opana ER “at-risk” in September 2013. Generic drugs are considered to have launched “at-risk” when they are launched before patent litigation over the branded drug has been resolved.

Actavis' generic has “already encroached on Endo’s bottom line,” Griesa said, with Actavis's infringing product directly responsible for 11 percent of Endo's loss of market share.

In addition, Griesa said, Endo had to slash its pain sales force by one quarter to reduce its promotional expenses and had to modify its research and development strategies as a result of the declining revenues.

“[T]he at-risk launch portends more harm to Endo if the court declines to grant Endo an injunction,” he wrote, adding that the harms to Endo aren't simply financial but also include reputational, organizational and administrative harms.

Endo's actual and potential losses of revenue, market share and customers “pose a true threat and require legal redress by this court,” Griesa wrote.

Authorized Generic Not Barred

Impax Laboratories Inc. also makes an authorized generic version of Opana ER that it started marketing in January 2013. Endo granted Impax a license to make the authorized generic as part of a patent litigation settlement.

“Endo's past license to Impax pursuant to a litigation settlement does not negate the harms Endo has experienced and would suffer in the future” from other generic products, he said.

Griesa's injunction doesn't extend to the authorized generic.

Actavis Could Pay Damages

Meanwhile, Actavis could be on the hook to pay substantial damages to Endo as a result of its at-risk launch if there is a final determination that it is liable for infringing the Endo patents. But there won't be a damages trial any time soon.

Although Endo asked the court to schedule a damages trial to calculate those damages, Griesa declined, citing the likelihood that the case would be appealed to the U.S. Court of Appeals for the Federal Circuit.

“Appeals from this court's decision on liability will inevitably follow, and any decision from the Federal Circuit will surely affect the damages phase of this case,” he wrote.

“It is prudent to await the resolution of any appeal before scheduling a damages trial or conducting discovery related to damages,” he said.

Griesa also declined to grant Actavis's request for a stay pending appeal.

Endo is based in Ireland, with its U.S. headquarters in Malvern, Pa.

Allergan Plc is based in Ireland. Actavis, its U.S. generics subsidiary, is based in Parsippany, N.J.

Roxane Laboratories, Inc., is now part of West-Ward Pharmaceuticals Corp., which is based in Eatontown, N.J.

The law firm of Dechert LLP in Mountain View, Calif., New York and Princeton, N.J., represented Endo.

The law firm of Holland & Knight LLP in New York represented Actavis Inc., now part of Allergan Plc.

The firms of Locke Lord LLP in Chicago and New York and the firm of Hedman & Costigan, P.C., New York represented Roxane.

To contact the reporter on this story: Dana A. Elfin in Washington at

To contact the editor responsible for this story: Brian Broderick at

For More Information

The opinion is at

Actavis's emergency motion for a stay pending appeal, filed with the Federal Circuit, is available here:

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