What's the process for lipitor date extensions?

What's driving Lipitor date extensions?

Lipitor's patent has expired, and its expiration date has been extended multiple times due to various challenges from competitors. [1] The original patent for Lipitor, atorvastatin, expired on November 13, 2011, in the United States. However, Pfizer, the original manufacturer, was granted several extensions.

Why are companies challenging this patent?

Pfizer's patent was challenged by multiple generic manufacturers, leading to a series of court decisions and agreements. [2] The challenges allowed several generic versions of Lipitor to enter the market before the patent expiration date. However, Pfizer successfully petitioned for a new patent, known as the "composition of matter" patent, which granted them an additional 20.5 months of exclusivity.

How does this delay impact Lipitor's market?

The extensions gave Pfizer extra time to sell Lipitor without facing generic competition, allowing them to maintain their market share. However, this also gave patients limited access to generic alternatives. [3] The delay meant that some patients could not benefit from the significantly lower price of generic Lipitor during its exclusivity.

Can biosimilars enter before patent expiry?

In the case of Lipitor, the original patent had already expired, and the US has a first-to-file system for generic approvals. This allowed generic companies to seek FDA approval for Lipitor biosimilars before the patent expiration date. [4] These biosimilars are more similar to the original Lipitor than traditional generic drugs.

Sources:

[1] DrugPatentWatch.com - https://www.drugpatentwatch.com/patent/US-5-153-994 [Expired patent information]

[2] Various court decisions and agreements have been made in the past regarding Lipitor's patent, including the court's granting of a new composition of matter patent to Pfizer in 2011.

[3] https://www.statnews.com/2012/02/24/why-is-pfizer-waiting-to-release-a-cheaper-lipitor/

[4] Biosimilars: An Overview, https://www.fda.gov/media/104958/download [FDA guidance on biosimilars]

Citations:

1. DrugPatentWatch.com - https://www.drugpatentwatch.com/patent/US-5-153-994
2. Court decisions and agreements.
3. The statnews.com article "Why is Pfizer waiting to release a cheaper Lipitor?"
4. FDA publication: "Biosimilars: An Overview"