AZ and BMS resolve checkpoint inhibitor patent disputes

AstraZeneca has said that a trio of lawsuits filed by Bristol-Myers Squibb and Ono Pharma alleging patent infringement with its checkpoint inhibitor drugs Imjudo and Imfinzi have now been resolved.

The company has set aside a $510 million provision to settle the lawsuits that it says "resolves all patent disputes" regarding its PD-L1 inhibitor Imfinzi (durvalumab) and recently launched CTLA4 inhibitor Imjudo (tremelimumab), used to treat various forms of cancer.

BMS filed an allegation of patent infringement over the marketing of Imfinzi in a Delaware court in 2022, claiming the drug infringed patents covering its PD-1 inhibitor Opdivo (nivolumab), with Ono Pharma and the Dana-Farber Cancer Institute joining the complaint later on.

Ono Pharma – a partner of BMS – also filed a complaint on similar patent infringement grounds in Japan last year, and that was followed in January by a BMS lawsuit alleging that Imjudo infringed two US patents covering the use of CTLA4 drugs used in combination with PD-1/PD-L1 inhibitors and chemotherapy.

BMS was the first company to bring a CTLA4 inhibitor to market, launching Yervoy (ipilimumab) in the US in 2011. Imjudo, meanwhile, was approved by the FDA last year for use in combination with Imfinzi for hepatocellular carcinoma and non-small cell lung cancer (NSCLC).

Legal complaints of this nature are not uncommon in pharma when drugs with the same mechanism reach the market. BMS and Ono previously won a similar dispute with MSD over its PD-1 inhibitor Keytruda (pembrolizumab) in 2017.

That resulted in a $625 million payment from MSD to settle all litigation and resulted in the company taking a non-exclusive license to patents and the payment of royalties on Keytruda sales through to 2026.

The settlement will be a relief for AZ, which highlighted the rapid growth of Imjudo and Imfinzi in its second-quarter results update last week, with collective sales of the two drugs rising 58% to $1.1 billion in the three-month period.

Imjudo's contribution currently remains relatively modest at around $100 million out of total first-half sales of almost $2 billion for the duo, but is expected to ramp up as it launches in additional markets and also if AZ can secure regulatory approvals in new indications, including bladder and urothelial cancers.

Yervoy made worldwide sales of around $1 billion in the first half of 2023, while Opdivo brought in $4.3 billion.