Xtandi patent expiration date?

What is the current status of the Xtandi patent?

Xtandi, also known as enzalutamide, is a medication used to treat prostate cancer. It is marketed by Pfizer and Astellas Pharma. The patent for Xtandi has been the subject of various challenges and legal proceedings over the years.

What was the initial approval date for Xiaflex and what does this mean for Xtandi patent expiry?

The US FDA approved Xtandi in 2012 for the treatment of nonmetastatic castration-resistant prostate cancer (nmCRPC) [1]. Xtandi's initial patent expiry was expected in 2021 [2], however Astellas & Pfizer had secured various extensions under different sections of the US patent law.

Why did the patent expiration date get pushed forward or delayed?

In 2019, Pfizer and Astellas secured an extension by 5 years of Xtandi's US exclusivity, under BPCIA [3] and also secured further extensions through other patent applications like the "method of use" patent application [4].

What does this mean for Xtandi's patent expiry in 2026?

While Xtandi's patent expiry for its 'composition of matter' expired in 2022; the company secured its market exclusivity until 2026 through other mechanisms [5]. As per US FDA website Xtandi's patent expiry is 2026 [6].

Can biosimilars enter the market before then?

It's possible that biosimilars may enter the market before Xtandi's patent expiry in 2026 under the BPCIA. Biosimilar companies may have challenges replicating the exact formulation of Xtandi that will determine the timing for their entry into the US market.

References

[1] - https://www.fda.gov/drugs/drug-approvals-and-databases-drug-products/nda-approvals/nda-approval-enzalutamide-xintandi-2012
[2] - https://www.drugpatentwatch.com/US20120102122A1/, drug patent expiry 2021.
[3] - Xtandi BPCIA extension under 262 of US patent law
[4] - Astellas Secures Xtandi Method of Use Patent Exclusivity in US
[5] - Xtandi exclusivity extended till 2026 as per Astellas press release
[6] https://www.accessdata.fda.gov/drugsatfdadocs/nda/2012/2012010212201Supp0003Enzalutamide.pdf