How does lipitor affect aspirin's antiplatelet action?

How does aspirin lose some of its antiplatelet effect when taken with Lipitor?

Lipitor (atorvastatin) can reduce aspirin's ability to block platelet aggregation. Laboratory studies show that atorvastatin interferes with the pathway aspirin uses to keep platelets from sticking together. This interference occurs mainly through atorvastatin's effect on protein kinase C, which aspirin relies on to acetylate COX-1 in platelets.

What happens if patients take both drugs?

Patients taking both aspirin and atorvastatin often still receive clinical benefit, but laboratory tests show reduced aspirin responsiveness. Reduced responsiveness measured by platelet function tests does not always translate into higher rates of cardiovascular events in large clinical trials. Large clinical trials such as PROVE IT-TIMI 22 and IDEAL did not detect a clinically meaningful interaction between statins and aspirin.

Why are companies challenging patents on atorvastatin?

No companies are actively challenging the expired patents on atorvastatin. Atorvastatin's compound patent expired in 2011, and pediatric exclusivity ended in 2012. The drug is now available as many generic versions.

How long does atorvastatin remain active in the body?

Atorvastatin and its metabolites remain active for about 20–30 hours. This time is long enough for tägliche Einnahme as daily dosing keeps plasma levels stable.

When does atorvastatin's exclusivity expire?

Atorvastatin has no remaining exclusivity periods. All major pharmaceutical patents and exclusivity periods on atorvastatin have expired.

Who makes Lipitor?

Pfizer originally developed and made Lipitor. The company released many generic manufacturers into the market after the 2011 patent expiry.