Lipitor is a popular medication used to treat high cholesterol levels. It is a brand name drug, and its patent expired in 2011, allowing for the production of generic versions. Generics are essentially identical copies of the brand-name drug, with the same active ingredients, strength, and dosage form.

According to DrugPatentWatch [1], there are currently several generic versions of Lipitor available on the market. These generics are manufactured by different companies and have different trade names, but they all contain the same active ingredient as Lipitor, which is atorvastatin calcium.

A study published in the National Library of Medicine [2] found that generic atorvastatin is as effective as Lipitor in reducing LDL cholesterol levels. The study compared the efficacy and safety of Lipitor and its generic version in patients with high cholesterol levels. The results showed that both drugs were equally effective in reducing LDL cholesterol levels, and there were no significant differences in side effects between the two drugs.

It is worth noting that there may be slight differences in the inactive ingredients used in the generic versions of Lipitor. These differences can affect the drug's absorption and metabolism in the body, but they are generally considered to be minor and do not affect the drug's overall effectiveness [3].

In conclusion, generic versions of Lipitor are as effective as the brand-name drug in reducing LDL cholesterol levels. They contain the same active ingredient and have been shown to have similar safety profiles. While there may be slight differences in the inactive ingredients used in the generic versions, these differences are generally considered to be minor and do not affect the drug's overall effectiveness.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5514478/
[3] https://www.humana.com/pharmacy/medication-information/difference-between-generic-and-brand-drug