Atorvastatin vs Pravastatin
## Overview
Atorvastatin and pravastatin occupy opposite ends of the statin potency spectrum. Pravastatin is a hydrophilic, non-CYP-metabolized statin with a distinctive safety profile, while atorvastatin is a lipophilic, high-potency, CYP3A4-metabolized agent.
## Mechanism of Action
Both inhibit HMG-CoA reductase. Pravastatin's hydrophilicity means it enters hepatocytes via active organic anion transporting polypeptides (OATP1B1/1B3) rather than passive diffusion, giving it relative hepatoselectivity and reducing skeletal muscle exposure.
## Pharmacokinetics
Pravastatin is not metabolized by cytochrome P450 enzymes; it is instead sulfated and undergoes conjugation. This makes it virtually free of CYP-mediated drug interactions. Its bioavailability is ~17% and half-life ~2 hours, requiring consistent daily dosing. Atorvastatin's CYP3A4 dependence creates important drug interactions but also produces active metabolites that extend its duration.
## Pharmacodynamics
Pravastatin achieves only 26–34% LDL-C reduction at maximum dose (80 mg), categorized as moderate-intensity. Atorvastatin at 40–80 mg achieves 37–51%, classified as high-intensity. For patients requiring maximal LDL-C lowering (e.g., FH, very high CV risk), pravastatin is insufficient.
## Clinical Evidence
Pravastatin's landmark trials include WOSCOPS (primary prevention), CARE, and LIPID (secondary prevention). These established the cardiovascular benefit of statin therapy broadly. The ALLIANCE trial directly compared atorvastatin with usual care (largely pravastatin) and showed atorvastatin achieved lower LDL and greater CV event reduction.
## Safety and Special Populations
Pravastatin's non-CYP metabolism makes it preferred in transplant patients on cyclosporine or tacrolimus (which inhibit CYP3A4 and OATP). It is also favored in HIV patients on antiretroviral protease inhibitors. Pravastatin has a better-documented safety record in elderly patients and does not cross the blood-brain barrier as readily due to hydrophilicity.
## Key Takeaways
- Pravastatin: hydrophilic, no CYP interactions, lower potency, preferred in transplant/HIV
- Atorvastatin: lipophilic, CYP3A4 substrate, high potency, preferred when aggressive lowering needed
- Both have robust outcome trial data
निष्कर्ष
Pravastatin is preferred when drug interactions are a paramount concern (transplant, HIV therapy). Atorvastatin is preferred for high-intensity LDL-C reduction in primary and secondary cardiovascular prevention.