What lab tests confirm lipitor's generic equivalence?

How are generic Liputors compared to the brand-name version?

According to the FDA, generic Lipitor (atorvastatin calcium) has been shown to be therapeutically equivalent to the brand-name version through bioequivalence testing [1]. The FDA requires that generic drugs demonstrate bioequivalence with the reference listed drug (RLD), which in this case is Lipitor.

Bioequivalence is confirmed through laboratory tests that compare the amount of the active ingredient (atorvastatin) in the patient's bloodstream after taking the generic version compared to the brand-name version. These tests typically involve a series of in vitro and in vivo studies, including:

* In vitro dissolution studies, which measure how quickly the active ingredient dissolves in water and is available for absorption.
* In vivo pharmacokinetic studies, which compare the plasma concentrations of atorvastatin after a single or multiple doses of the generic and brand-name versions.

Who conducts these tests?

Pharmaceutical companies that seek to market a generic version of Lipitor must conduct these tests as part of their Abbreviated New Drug Application (ANDA) to the FDA. In the case of generic Lipitor, several companies have submitted ANDAs demonstrating bioequivalence.

What are the regulatory requirements for generic Lipitor equivalence?

Under Section 505(b)(2) of the Federal Food, Drug, and Cosmetic Act (FDCA), generic versions of branded drugs (like Lipitor) can be approved more quickly by relying on previously accepted efficacy and safety data from the RLD [2]. To qualify for approval under this pathway, generic manufacturers must demonstrate bioequivalence with the RLD through these lab tests.

According to the FDA, there are several generic versions of Lipitor approved for the market, which have met the necessary bioequivalence criteria.

When will the Lipitor patent expire?

The Lipitor patent has already expired. The patent for atorvastatin calcium expired in the United States in 2011, allowing generic versions of the medication to enter the market.

Sources:
[1] https://www.fda.gov/drugs/biosimilars-and-generics/guidance-development-and-submission-biosimilars
[2] https://www.fda.gov/regulated-industries/pharmaceutical-quality-manufacturing/abbreviated-new-drug-application-anda
https://www.drugpatentwatch.com/patent/2020/05/19/US-6162960

Sources (listed sequentially):
1. https://www.fda.gov/drugs/biosimilars-and-generics/guidance-development-and-submission-biosimilars
2. https://www.fda.gov/regulated-industries/pharmaceutical-quality-manufacturing/abbreviated-new-drug-application-anda
3. https://www.drugpatentwatch.com/patent/2020/05/19/US-6162960