The length of Lipitor treatment varies for each individual and is typically determined by a healthcare provider based on the patient's health status, response to the medication, and risk of cardiovascular disease. According to the American College of Cardiology and American Heart Association's 2018 cholesterol guidelines [1], statins such as Lipitor are recommended for individuals with a high risk of atherosclerotic cardiovascular disease (ASCVD) and LDL cholesterol levels ≥70 mg/dL.

For patients with clinical ASCVD, the recommendation is to continue statin therapy indefinitely as long as the benefits outweigh the risks [1]. However, for primary prevention, the duration of Lipitor treatment should be evaluated periodically and may be discontinued if the patient's risk of ASCVD is low and the potential for adverse effects outweighs the benefits.

It is important to note that Lipitor, like other statins, can have side effects such as muscle pain and liver damage [2]. Regular monitoring of liver enzymes and muscle function is recommended during Lipitor treatment.

In terms of patent information, Lipitor (atorvastatin) was first approved by the FDA in 1996 and its patent expired in 2011 [3]. Generic versions of atorvastatin are now available, which may affect the cost and accessibility of the medication.

In conclusion, the duration of Lipitor treatment depends on various factors, including the patient's risk of ASCVD and response to the medication. Regular evaluations with a healthcare provider are necessary to determine the appropriate length of Lipitor treatment.

Sources:

1. Grundy SM, Stone NJ, Bailey AL, Beam C, Birtcher KK, Blumenthal RS, et al. 2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA Guideline on the Management of Blood Cholesterol: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation. 2019;139(25):e1082-e1143. doi:10.1161/CIR.0000000000000625
2. Lipitor (atorvastatin) [prescribing information]. Whitehouse Station, NJ: Pfizer Inc; 2018.
3. Atorvastatin Calcium. DrugPatentWatch.com. <https://www.drugpatentwatch.com/drugs/atorvastatin-calcium>. Accessed March 15, 2023.