Douglas Carsten

On Dec. 6 last year, Carsten argued four separate matters before the Federal Circuit. All the cases dealt with patents that global pharmaceutical company Sanofi-Aventis accused Mylan Pharmaceuticals, Carsten's client, of infringing.

"It was a very long day for everybody," Carsten said about the three judges and the three attorneys on the other side who participated in the arguments.

But it didn't take long for the judges to reach their decisions. On Dec. 29, the circuit ruled for Mylan on all the cases, putting an end to a four-year battle to allow Mylan, now part of Viatris Inc., to bring out a lower-cost version of a product that combines a long-lasting insulin with an injector pen.

Over that litigation, Carsten and his team vanquished 18 Sanofi patents, either because the company withdrew them or because the PTAB or a court held them unpatentable. "That's what happens when you try to stretch a patent to cover something you didn't invent in the first place," he said.

Carsten specializes to a large extent in cases under the Hatch-Waxman Act on generic drugs. In the past, he mostly represented the generic makers, but since moving to McDermott a year ago, he represents the brand drug makers almost exclusively, he said.

Thus last month, he tried a Hatch-Waxman case on behalf of a company that sells a brand-name drug to treat pulmonary arterial hypertension against a generic-maker that wants to use his client's data to support its New Drug Application. United Therapeutics Corp. v. Liquidia Technologies Inc., 1-20-cv-00755 (D. Del., filed June 4, 2020).

He moved to McDermott because he had a dream to build a great life-sciences patent group, and so far, the project is going well, he said. "I've always loved life sciences cases, and I think that really is where the action is these days."

What he enjoys most about patent litigation is learning the science involved well and making it understandable and relatable to jurors and judges. "That's the magic. I love doing that," he said.

A case several years ago dealt with patenting "protecting groups" used when constructing a large, complicated organic molecule. The groups are inserted to guard an area of the molecule and then removed when no longer needed. Carsten wanted to explain that simply, and he figured out how in the paint aisle at Home Depot.

"I see these painter's tapes. One's blue, and Frog Tape is green. But they all do the same thing." Just like his client's and the other side's protecting groups. "They're going to say our painter's tape is green," he told the judge. "But at the end of the day, it does exactly the same thing exactly the same way." The judge was convinced.

His use of humor aligns with Carsten's career path. His first career was as an organic chemist. He switched to law after seeing "My Cousin Vinny."

- Don DeBenedictis