China-based CSPC Pharmaceutical Group Co., Ltd (HKG: 1093) has obtained market approval from the National Medical Products Administration (NMPA) for its generic version of Roche’s (SWX: ROG) Xofluza (baloxavir marboxil) on October 11, 2022. This approval marks a significant development in the availability of generic influenza treatments in China. However, the approval is not without controversy, as Roche has noted that its Xofusa remains patent-protected under patent NO. ZL201180056716.8, which is valid until September 21, 2031.
Roche’s Patent and Legal Stance
Under China’s Patent Law, Roche asserts that CSPC should not be permitted to use, sell, or offer to sell baloxavir marboxil without the permission of the patent holder. Roche has been in communication with Shijiazhuang Pharmaceutical Group Ouyi Pharma Co., Ltd since July 2021 regarding the intellectual property issue. However, Ouyi Pharma has declined to promise not to conduct any patent infringement during the patent protection period, while acknowledging that its approved generic falls within the scope of the patent.
Xofluza: Drug Profile and Development
Xofluza, a first-in-class single-dose oral drug co-developed by Japan-based Shionogi & Co., Ltd, inhibits virus replication by targeting cap-dependent endonuclease in the influenza virus. It is effective against oseltamivir-resistant virus strains and avian influenza virus strains (H7N9, H5N1). The drug was approved in the US in October 2018 for use in acute influenza patients over 12 years of age without complications, marking the first new mechanism of action in anti-influenza drugs in two decades. It received another indication approval in the US in December 2019 for high-risk influenza complication populations aged 12 years and above. A market filing for the drug was made in China in June 2020, and it entered the third batch of clinically urgently needed drugs already approved overseas in October 2020. Roche’s product was approved in China on April 27, 2021, following a priority review status award.
Regulatory and Patent Linkage Considerations
According to the “Implementation Measures for Drug Patent Early Dispute Resolution Mechanism” released by the NMPA and the China National Intellectual Property Administration (CNIPA), chemical generic drug applicants are required to make a declaration regarding the patent status of a filing based on information published in the national patent drug catalogue. However, this policy took effect from July 5, 2021, while CSPC’s market filing for its generic drug was accepted for review by the NMPA on July 1, 2021, four days prior to the official implementation date of the patent linkage system. As a result, no information about the patent challenge has been found on the website.
Future Outlook
The approval of CSPC’s generic version of Xofluza highlights the ongoing debate over patent protection and generic drug availability in China. Roche has filed a patent infringement lawsuit against the generic market filing, adding further complexity to the situation. The outcome of this legal challenge will have significant implications for both CSPC and Roche, as well as for the broader pharmaceutical industry in China.-Fineline Info & Tech
