Molecule

Drug Groups

approved; investigational

Description

Lovastatin is a cholesterol-lowering agent that belongs to the class of medications called statins. It was the second agent of this class discovered. It was discovered by Alfred Alberts and his team at Merck in 1978 after screening only 18 compounds over 2 weeks. The agent, also known as mevinolin, was isolated from the fungi Aspergillus terreus. Research on this compound was suddenly shut down in 1980 and the drug was not approved until 1987. Interesting, Akira Endo at Sankyo Co. (Japan) patented lovastatin isolated from Monascus ruber four months before Merck. Lovastatin was found to be 2 times more potent than its predecessor, mevastatin, the first discovered statin. Like mevastatin, lovastatin is structurally similar to hydroxymethylglutarate (HMG), a substituent of HMG-Coenzyme A (HMG-CoA), a substrate of the cholesterol biosynthesis pathway via the mevalonic acid pathway. Lovastatin is a competitive inhibitor of HMG-CoA reductase with a binding affinity 20,000 times greater than HMG-CoA. Lovastatin differs structurally from mevastatin by a single methyl group at the 6’ position. Lovastatin is a prodrug that is activated by in vivo hydrolysis of the lactone ring. It, along with mevastatin, has served as one of the lead compounds for the development of the synthetic compounds used today.

Indication

For management as an adjunct to diet to reduce elevated total-C, LDL-C, apo B, and TG levels in patients with primary hypercholesterolemia and mixed dyslipidemia. For primary prevention of coronary heart disease and to slow progression of coronary atherosclerosis in patients with coronary heart disease.

Pharmacology

The primary cause of cardiovascular disease is atherosclerotic plaque formation. Sustained elevations of cholesterol in the blood increase the risk of cardiovascular disease. Lovastatin lowers hepatic cholesterol synthesis by competitively inhibiting HMG-CoA reductase, the enzyme that catalyzes the rate-limiting step in the cholesterol biosynthesis pathway via the mevalonic acid pathway. Decreased hepatic cholesterol levels causes increased uptake of low density lipoprotein (LDL) cholesterol and reduces cholesterol levels in the circulation. At therapeutic doses, lovastatin decreases serum LDL cholesterol by 29-32%, increases high density lipoprotein (HDL) cholesterol by 4.6-7.3%, and decrease triglyceride levels by 2-12%. HDL cholesterol is thought to confer protective effects against CV disease, whereas high LDL and triglyceride levels are associated with higher risk of disease.

Toxicity

LD₅₀>1000 mg/kg (orally in mice)

Affected Organisms

Biotransformation

Undergoes first pass hydrolysis to active metabolites β-hydroxyacid and 6'-hydroxy dervative.

Absorption

< 5%. Time to peak serum concentration is 2-4 hours.

Half Life

5.3 hours

Protein Binding

> 95%

Elimination

Lovastatin undergoes extensive first-pass extraction in the liver, its primary site of action, with subsequent excretion of drug equivalents in the bile. 83% of the orally administered dose is excreted in bile and 10% is excreted in urine.

References

External Links