Palonosetron – USA

On Feb 14, 2017, A New Jersey federal judge found that Dr. Reddy’s Laboratories Inc.’s palonosetron product infringed patents on Helsinn Healthcare SA’s anti-nausea drug (Aloxi) and rejected Dr. Reddy’s contention that two of those patents are invalid.

DRL submitted NDA No. 203050 to the FDA pursuant to the Hatch-Waxman Act, 21 U.S.C. § 505(b)(2), seeking approval to market its own palonosetron product. The patents covered by DRL’s Paragraph IV certifications include U.S. Patent Nos. 7,947,724 (“the ’724 patent”); 8,729,094 (“the ’094 patent”); and 9,066,980 (“the ’980 patent”). Helsinn contends that DRL’s Accused Product infringes thirteen claims in the Asserted Patents. DRL has raised the defense of non-infringement for three of those claims and argues that the other ten are invalid.

Infringement

DRL’s Accused Product contains sodium acetate trihydrate and it asserted that it idoes not fall under the definition of chelating agent. Claim construction construed the term “chelating agent” to mean a “multidentate ligand that can form a ring structure by reacting with a metal ion. The court based on a review of all of the evidence presented at trial, and as reflected in the findings of fact above, concluded that Helsinn proved by a preponderance of the evidence that the acetate present in DRL’s product is a multidentate ligand that can form a ring structure by reacting with a metal ion. Accordingly, the Accused Product contains a “chelating agent”.

Invalidation

DRL raised Enablement and Written Description grounds for invalidity. On enablement court said that weighing the relevant Wands factors, we conclude that the totality of this evidence does not support a finding that undue experimentation would be necessary to practice the asserted claims. On Written Description ground court said that we have considered the arguments and evidence presented by DRL and the countervailing arguments and evidence by Helsinn, and find that Helsinn’s evidence is more persuasive on the matter of written description.

Therefore we conclude that DRL has failed to meet its burden of demonstrating, by clear and convincing evidence, that the asserted claims are invalid for lack of enablement or lack of written description.