Lipitor, also known as atorvastatin, is a medication used to treat high cholesterol levels. Its primary protein targets are HMG-CoA reductases. HMG-CoA reductases are enzymes that play a crucial role in the production of cholesterol in the body. By inhibiting these enzymes, Lipitor reduces the amount of cholesterol produced in the body, which in turn helps to lower the levels of cholesterol in the blood. This mechanism of action helps to reduce the risk of heart attacks and strokes in patients with high cholesterol.

According to DrugPatentWatch.com, Lipitor was first approved by the FDA in 1996 and its patent expired in 2011. Since then, several generic versions of the drug have become available on the market. Despite the availability of generics, Lipitor remains one of the most widely prescribed medications for high cholesterol.

In summary, Lipitor's primary protein targets are HMG-CoA reductases, which are enzymes involved in the production of cholesterol in the body. By inhibiting these enzymes, Lipitor reduces the amount of cholesterol produced in the body, which helps to lower the levels of cholesterol in the blood and reduce the risk of heart attacks and strokes in patients with high cholesterol.

Sources:

* [DrugPatentWatch.com - Lipitor](https://www.drugpatentwatch.com/drugs/lipitor)