Allergan Victory in ALPHAGAN® P Patent Infringemet Suit

The United States District Court for the District of Delaware handed Allergan, Inc. (NYSE:AGN) a victory last week in its patent infringement lawsuit brought against Exela PharmSci, Inc., Exela PharmSci Pvt., Ltd., Apotex, Inc. and Apotex Corp. The defendants had been seeking permission to market generic versions of Allergan’s drugs ALPHAGAN® P, which is indicated for the lowering of intraocular pressure (IOP) in patients with open-angle glaucoma or ocular hypertension. The patent infringement trial took place in March of 2009, but a final ruling was not handed down by the district court until Friday, October 23, 2009. Such a length of time between trial and handing down a decision is not uncommon, and at least several months can be expected in a patent litigation, particularly where the science is complex.

In any event, the district court ruled that all five Allergan patents, specifically U.S. Patent Nos. 6,627,210; 6,641,834; 6,673,337; 6,562,873; and 5,424,078, were appropriately granted by the United States Patent and Trademark Office and are fully enforceable. Those following this litigation will probably read elsewhere that the district court determined the patents were valid. While a good short-hand description of the ruling, issued patents are not declared valid, but rather are presumed valid and will remain valid unless and until a defendant in a litigation can demonstrate by clear and convincing evidence that the patent should not have been issued, typically because the innovation at issue was determined not to be new or unique enough compared with other inventions.

The procedural posture of this litigation is not an uncommon one in the pharmaceutical industry. The defendants filed what is known as an Abbreviated New Drug ApplicationHatch-Waxman Act (ANDA) with the Food and Drug Administration, seeking approval to market a generic version of Allergan’s ALPHAGAN® P products, both in the 0.15% and 0.10% formulations. The ANDA’s contained the familiar “Paragraph IV certification,” which states that it is the believe of the would-be generic manufacturer that the underlying patents covering the brand name version of the drug are either invalid or unenforceable, or that if valid and unenforceable would not be infringed by the making of a generic version of the drug. As a result of the language of the applicable statute, known as the , such a Paragraph IV certification is deemed to constitute an act of infringement allowing the patent owner to institute a patent infringement proceeding against the filers of the ANDA, which Allergan in fact did in this case.

Pursuant to the Hatch-Waxman Act, the FDA is now required to delay approval of Defendants’ proposed generic products until the last to expire of the infringed patents, which is 2022. An appeal to the United States Court of Appeals for the Federal Circuit is possible, and perhaps even extremely likely given the amount of money potentially at stake should earlier market entry of a generic be ultimately allowed.

For more information onFDA regulation of generic drugs and the Hatch Waxman Act see:



Warning & Disclaimer: The pages, articles and comments on do not constitute legal advice, nor do they create any attorney-client relationship. The articles published express the personal opinion and views of the author as of the time of publication and should not be attributed to the author’s employer, clients or the sponsors of

Join the Discussion

One comment so far.