Genentech and Amgen Cease Fire on Biosimilar Litigation

In court filings this week, Genentech and Amgen laid to rest their long-running dispute over the marketing of bevacizumab and trastuzumab biosimilars that challenged Genentech's dominance of the market for those products.

Having been stopped by court rulings in its attempt to block 2 Amgen biosimilars from coming to market, Genentech waved the white flag this week by filing a court notice of settlement with Amgen. The notice indicated that both had agreed to relinquish all claims and counterclaims.

The battles waged over separate drugs involved Amgen’s trastuzumab biosimilar Kanjinti and bevacizumab biosimilar Mvasi. Kanjinti references Genentech’s Herceptin, and Mvasi is a biosimilar to Avastin.

A Court Ruling With Ripple Effects

The struggle over Kanjinti was a wake-up call to originator companies, in that they would have to become more circumspect in their timing of court actions; and the Mvasi fight came to a turning point earlier this week when a federal circuit court overruled Genentech’s claims of inadequate notice of commercialization.

Both Kanjinti and Mvasi came to market in July 2019. With Kanjinti, Genentech delayed too long—almost a month after the FDA approved the drug for sale—before filing a motion for an injunction to block commercialization of the product. When Genentech finally did file that motion, a district court judge refused to grant the injunction, which allowed Amgen to bring the trastuzumab product to market.

Similarly, an appeal of that decision was turned down by the US Court of Appeals for the Federal Circuit in March.

Having witnessed Genentech get singed by that ruling, other originator companies are likely to make sure they file for injunctions earlier in the process and, certainly, before the FDA issues marketing authorization to biosimilar developers, patent law attorney Ted Mathias, of Axinn, Veltrop & Harkrider of Hartford, Connecticut, concluded in a presentation earlier this year.

“We can expect some changes and, specifically, some more varied approaches to litigation based on what we saw last year with trastuzumab,” Mathias said.

What that earlier notice signifies is that originator companies will have to play stronger cards against rival biosimilar companies earlier in the patent review process, thereby revealing more about their products and exclusivity protections and, potentially, tipping their hands to competitor biosimilar companies, Mathias said. It essentially gives rivals an advantage in the legal process that they didn’t have previously.

When Does the Notice Clock Start Ticking?

Whereas timing was a critical flaw in Genentech’s attempt to block commercialization of Kanjinti, Genentech’s latest move to halt Mvasi sales hinged on whether Amgen had provided adequate notice of commercialization. The Biologics Price Competition and Innovation Act calls for at least 180 days of notice prior to marketing, but Genentech argued that some adjustments to the Biologics License Application (BLA) for Mvasi reset the clock on the notice requirement, which would have forced Amgen to start again. A district court disagreed with that argument, saying the adjustments were immaterial to the substance of the BLA, and a federal circuit court upheld that ruling.

Both the trastuzumab and bevacizumab biosimilars from Amgen have been carving an ever-increasing share of the market away from Genentech since launching in July of last year. Both launched at a 15% discount to the respective Genentech originator products, Herceptin and Avastin, which can be conceived to have been helpful in gaining sales momentum.

Kanjinti notched $226 million in 2019, and $119 million in the first quarter of this year. The respective sales figures for Mvasi were $127 million and $115 million. Here are links to the 2019 and 2020 Amgen sales reports.