Roche Sues Pfizer Over Proposed Trastuzumab Biosimilar

Swiss drug maker Roche has filed a lawsuit against Pfizer in a Wilmington, Delaware federal court, seeking to block the rival developer from launching a biosimilar trastuzumab in the United States.

Bloomberg Technology reports that Roche subsidiary Genentech, maker of the blockbuster Herceptin, claims that a biosimilar would infringe on 40 of its patents. Genentech’s complaint asks the court to order compensation for lost sales if Pfizer launches a biosimilar prior to Herceptin’s US patent expiry.

While this legal action marks the first time Roche has sued over a biosimilar in a United States court, the lawsuit is not the first legal challenge related to Pfizer’s development of its proposed trastuzumab molecule. In July 2017, the US Patent Trial and Appeal Board (PTAB) instituted Pfizer’s petitions for inter partes reviews (IPRs) filed by Pfizer subsidiary Hospira against 3 patents covering Herceptin (though the PTAB denied an IPR petition for a fourth patent). Then, in October 2017, Pfizer filed another petition for an IPR of an additional Herceptin patent.

Legal action over trastuzumab is also not Pfizer’s first foray into legal battles over biosimilars; Pfizer launched the first biosimilar infliximab product (Inflectra) in the United States in October 2016, and has proactively litigated against Johnson & Johnson, sponsor of the reference infliximab (Remicade), claiming that Johnson & Johnson engaged in anti-competitive practices that were intended to block Inflectra from gaining formulary placement.

While Pfizer has not yet announced its submission of a Biologics License Application for its proposed trastuzumab biosimilar, it has released positive data from a comparative clinical trial comparing PF-05280014 to reference trastuzumab in patients with operable HER2-positive early breast cancer. The study demonstrated that PF-05280014 had similar safety, efficacy, and immunogenicity to its reference, and that it was non-inferior, in terms of pharmacokinetics, to the reference drug.

Pfizer’s pipeline also contains a number of other proposed biosimilars; the drug maker reports that it is in phase 3 development of biosimilars referencing adalimumab (Humira), bevacizumab (Avastin), epoetin alfa (Epogen, Procrit), and rituximab (Rituxan, MabThera). Forbes reports that the total sales of the reference products targeted by Pfizer totaled over $35 billion in 2014, and that “Theoretically speaking, replacing [these drugs’] entire sales with biosimilars even with a 50% pricing discount will open up a market worth nearly $18 billion for Pfizer.”