Atorvastatin vs Simvastatin

Atorvastatin and simvastatin are two popular cholesterol lowering medications.

Atorvastatin is available in the US market under the band name Lipitor (Pfizer). Simvastatin was originally sold under the brand name Zocor but now is widely available under its generic name because of patent expiry. Lipitor patent protect protection expires on Nov 30, 2011, which will result in atorvastatin price decrease and generic medication availability.

There were a number of researches comparing simvastatin vs atorvastatin. Both the medications seem to work equally well. However, the information and studies comparing simvastatin vs atorvastatin are sometimes controversial, which is natural in the light of the growing competence in the drug market. We’ll list some the objectives and findings below.

"A Comparison of Simvastatin and Atorvastatin up to Maximal Recommended Doses in a Large Multicenter Randomized Clinical Trial".

(Researchers: D. Roger Illingworth, Donald B. Hunninghake, John R. Crouse III, Ivan D. Escobar, Michael H. Davidson, Anton F. H. Stalenhoef, Minzhi Liu,Gyorgy Paragh, Michael R. Melino, Patrick T. S. Ma, Laura O’Grady, Michele Mercuri and Yale B. Mitchel for the Simvastatin Atorvastatin HDL Study Group) Simvastatin was found more effective than atorvastatin at raising HDL cholesterol and apo A-I levels in hypercholesterolemic patients, which suggests that statins differ in their capacity to raise HDL cholesterol. The objective of the 36-week, double-blind, randomized, dose-titration study involving826 hypercholesterolemic participants.

"High-Dose Atorvastatin vs Usual-Dose Simvastatin for Secondary Prevention After Myocardial Infarction"

(Researchers: Terje R. Pedersen, MD, DMSc; MD, PhD; Ole Faergeman, MD, PhD; Anders G. Olsson, John J. P. Kastelein, MD, PhD; Matti J. Tikkanen, MD, PhD; PhD; Mogens Lytken Larsen, Ingar Holme, MD, DMSc; MD; Christina Lindahl, Fredrik S. Bendiksen, MD; Michael Szarek, MS; John Tsai, MD; for the Incremental Decrease in End Points Through Aggressive Lipid Lowering (IDEAL) Study Group). The purpose of the study was to compare lipid lowering effects of simvastatin and atorvastatin on the risk of cardiovascular disease in patients who had myocardial infarction. Researchers found that intensive lowering of LDL-C with the help of simvastatin and atorvastatin did not reduce the primary outcome of major coronary events. However, reduction of other composite secondary end points and nonfatal acute MI was observed for both atorvastatin and simvastatin. Also, serious rhabdomyolysis and myopathy were scarce in both study groups. No differences in all-cause or cardiovascular mortality were observed, which means that intensive LDL-C lowering treatment is beneficial for patients with MI without an increase in noncardiovascular mortality or other serious adverse reactions. However, the rates of drug discontinuation due to non-serious side effects were higher atorvastatin group.

Atorvastatin compared with simvastatin-based therapies in the management of severe familial hyperlipidaemias

(Researchers:A.S. Wierzbicki, P.J. Lumb, Y. Semra, G. Chik, E.R. Christ1 and M.A. Crook)

Atorvastatin proved to be more effective in lowering LDL cholesterol levels than simvastatin, however, the occurrence of side effects was higher.

Atorvastatin vs Simvastatin: Triglycerides Reduction:

Researches at the Department of Geriatrics and Metabolic Diseases, Second University of Naples, Italy (Gentile S, Turco S, Guarino G, Sasso CF, Amodio M, Magliano P, Salvatore T, Corigliano G, Agrusta M, De Simone G, Gaeta I, Oliviero B, Torella R.) found that atorvastatin is much more effective in triglycerides reduction than all other statins (including simvastatin).

Summing up all of the above, atorvastatin vs simvastatin comparison looks like this:

Numerous studies suggest that atorvastatin is more effective than simvastatin in lowering LDL-cholesterol levels, however, at the cost higher and more severe occurrence of side-effects, which caused many patients to discontinue the medication.

As atorvastatin proved to be more effective in lowering LDL cholesterol levels than simvastatin, the same LDL lowering effect requires lower dose of atorvastatin than simvastatin.

Simvastatin is more effective than atorvastatin at raising HDL cholesterol and apo A-I levels in hypercholesterolemic patients.

As to price comparison, simvastatin is the winner for now because atorvastatin is still under patent protection in the USA so the costs of the medication are still too high due to lack competition. However, the patent expires on Nov 30, 2011, so Lipitor will be available as a generic version - atorvastatin.

According to the latest FDA guides, atorvastatin should be preferred over simvastatin 80mg doses in patients who have been taking simvastatin 80 mg for less than a year because of higher occurrence of myopathy and rhabdomyolysis in patients on simvastatin 80 mg. However, this recommendation should not be seen as simvastatin discrediting because simvastatin 80mg is not a common but the highest admissible dose which is only prescribed when the need to lower cholesterol is more important than the dangers of simvastatin side effects. . The recommendation sounds logical considering that lower dose of atorvastatin is required for the same therapeutic effect.

And the last, some doctors express the opinion that the studies discrediting simvastatin are the result of marketing efforts of Pfizer. Switching to atorvastatin for patients taking lower doses of simvastatin and having smaller cholesterol lowering need is not recommended by many doctors.

Atorvastatin to Simvastatin Switching

Atorvastatin / simvastatin switching makes significant cost-saving sense without significant negative clinical consequences

Simvastatin to Atorvastatin Switching

Simvastatin to atorvastatin Switching can be recommended to patients who have been taking Simvastatin 80 mg for less than one year or developed serios side effects.

Atorvastatin to Simvastatin: Equivalent Dosage

According to clinical practice, Atorvastatin 10 mg is equivalent to simvastatin 20 mg.