With $2.5B in Herceptin sales on the line, Roche sues Pfizer for biosim patent infringement

Bringing biosimilars to market isn't an easy proposition, as Pfizer and its fellow biosimilar makers continue to discover. In another hurdle Pfizer will have to clear, Roche has sued for infringement of 40 patents protecting its blockbuster breast cancer med Herceptin.

In a complaint in Delaware federal court, Roche claims that Pfizer's FDA application for its proposed biosim amounts to patent infringement. It's asking the court to agree—and to block a potential launch.

The Swiss cancer giant says its Genentech unit has spent "over two decades, and billions of dollars, developing Herceptin into the life-saving drug it is today." Pfizer is seeking to piggyback off that work by using Roche studies to prove safety and efficacy, the lawsuit claims.

Importantly, Pfizer hasn't yet won approval for its Herceptin biosim. The FDA accepted its application in August, according to the lawsuit. Herceptin brought in $2.5 billion in the U.S. last year for Roche and is set to lose some patent protections in 2019.

A Pfizer representative said the company "will respond in court at the appropriate time."

"We’re committed to making this important treatment option available to physicians and patients," the Pfizer spokesman continued. According to Bloomberg, it's the first time Roche has filed a patent lawsuit against a biosim challenger to Herceptin.

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Aside from Pfizer, Mylan is looking to challenge the Roche blockbuster with its own biosim. The company entered a deal with Roche earlier this year that will provide it licenses to market its product in countries around the world after an undisclosed date. In return, the company dropped a patent challenge at the U.S. Patent and Trademark Office.

But Mylan recently suffered a delay at the FDA as the agency put off its decision deadline by three months to Dec. 3. Mylan's partner Biocon said the delay wouldn't impact the U.S. launch timeline.

Even if Pfizer makes it to market with its Herceptin biosim, now called PF-05280014, the company faces an uphill fight to win significant sales, as early results from the emerging biosimilars market have shown.

Pfizer's version of Johnson & Johnson megablockbuster Remicade, Inflectra, hasn't gained much traction yet, and the drugmaker recently sued J&J blaming its rival for the biosimilar's struggles. Pfizer claims "anticompetitive" contracting has blocked access to its discounted version of Remicade, one of J&J's biggest products.

According to Pfizer, J&J has tied rebates on current Remicade patients to the stipulation that payers avoid biosims, effectively shutting out the competition. J&J countered that Pfizer's product isn't offering payers enough value to win their business.

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Branded companies have routinely sued potential biosimilar challengers as they look to defend their key meds. The Biologics Price Competition and Innovation Act introduced a process for companies to interact and determine whether biosims would infringe patents, but branded drugmakers often argue biosim companies don't participate. The brand makers sometimes resort to the legal process to discover whether their patents may be infringed.

In a landmark ruling earlier this year, the Supreme Court ruled that violations of the BPCIA process, called the "patent dance," aren't enforceable by an junction at the federal court level. The court also ruled that biosim makers can provide a required six-month marketing notice before an FDA approval, enabling them to launch faster after winning an FDA nod.