By Alejandra Manjarrez www.biospace.com

Pictured: Judicial gavel and scales of justice/iStock

AbbVie has filed a lawsuit accusing China-based BeiGene’s new blood cancer drug Brukinsa (zanubrutinib) of infringing on its patent for Imbruvica (ibrutinib). Imbruvica was co-developed by J&J’s Janssen and AbbVie’s Pharmacyclics and approved in 2014 by the FDA as a treatment for chronic lymphocytic leukemia.
Brukinsa, which gained its FDA approval in January 2023, had its patent issued on Tuesday. Through its complaint, filed that same day in federal court in Delaware, AbbVie is seeking a declaratory judgment of infringement plus damages, Bloomberg Law reported.
BeiGene’s shares in Hong Kong and mainland China have fallen more than 10% since the announcement.
Both Brukinsa and Imbruvica are BTK inhibitors designed as oral medications to treat the slow-growing blood cancers chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL). They are different forms of the same disease and account for about a quarter of new cases of leukemia diagnosed in the U.S. AstraZeneca also has a BTK inhibitor commercialized under the name of Calquence.
“It is an unfortunate but rather regular occurrence that companies make allegations that a competitive product potentially infringes their intellectual property rights, even more so in response to a clearly differentiated medicine for cancer patients as Brukinsa,” said BeiGene in a press release .
In a recent Phase III clinical trial, BeiGene’s Brukinsa outperformed AbbVie’s Imbruvica in treating patients with relapsed or refractory CLL or SLL. The results of the head-to-head trial showed that progression-free survival was significantly longer among patients receiving Brukinsa compared to those treated with AbbVie's therapy.
In terms of safety, Brukinsa was also superior. For instance, patients treated with it were less likely to experience cardiac adverse events.
Based on their compared toxicity, the National Comprehensive Cancer Network placed Brukinsa ahead of Imbruvica in their guidelines to treat these slow-growing blood cancer.
In the first quarter of 2023, Brukinsa’s worldwide sales reached $211.4 million, up significantly from $104.3 million a year ago. Imbruvica’s sales, on the other hand, dropped 25% in the first quarter of 2023 compared to the same period in 2022.
BeiGene’s statement emphasized that the company “has developed original and novel intellectual properties” around Brukinsa to “demonstrate its differentiated profile,” while insisting that they “will vigorously defend against all allegations of patent infringement.”