Related Experiment Videos
Relationship between atorvastatin dose and the harm caused by torcetrapib
Philip J Barter1, Kerry-Anne Rye, Mohan S Beltangady
1The Heart Research Institute, Sydney, Australia. barterp@hri.org.au
Journal of Lipid Research
|September 4, 2012
Summary
The cholesteryl ester transfer protein (CETP) inhibitor torcetrapib caused harm, specifically increased mortality and cardiovascular events, but only in patients taking a low dose (10 mg) of atorvastatin. Higher atorvastatin doses appeared to mitigate these risks.
Area of Science:
- Cardiovascular Pharmacology
- Clinical Trial Analysis
- Drug Safety Evaluation
Background:
- Development of cholesteryl ester transfer protein (CETP) inhibitor torcetrapib was halted due to safety concerns.
- The ILLUMINATE trial indicated increased all-cause mortality (ACM) and major cardiovascular events (MCVEs) with torcetrapib use.
Purpose of the Study:
- To investigate the specific patient subgroup experiencing harm from torcetrapib.
- To determine if the dose of atorvastatin influenced torcetrapib-associated risks.
Main Methods:
- Subgroup analysis of the ILLUMINATE trial data.
- Statistical analysis of ACM and MCVEs in relation to torcetrapib and atorvastatin dosage.
- Multivariable regression to adjust for clinical risk factors.
Main Results:
- Torcetrapib-associated harm (ACM and MCVEs) was confined to the 10 mg atorvastatin subgroup.
- No increased risk was observed when torcetrapib was coadministered with higher doses of atorvastatin.
- Adjusting for baseline risk factors did not alter the observed harm in the 10 mg atorvastatin subgroup.
Conclusions:
- The adverse effects of torcetrapib were specifically linked to coadministration with low-dose atorvastatin (10 mg).
- Higher doses of atorvastatin may offer a protective effect against torcetrapib-induced harm.
- The mechanism of harm is independent of lipid changes, blood pressure, or electrolytes.
Related Concept Videos
01:20Lipid-Lowering Drugs: Statins and Miscellaneous Agents
Hyperlipidemia, a medical condition often referred to as high cholesterol, is characterized by abnormally elevated levels of lipids in the bloodstream. When present in excess, these lipids, specifically cholesterol and triglycerides, can lead to serious health complications, often involving cardiovascular diseases. Illnesses like atherosclerosis, heart attacks, and pancreatitis have all been linked to untreated hyperlipidemia. This means controlling and regulating cholesterol and triglyceride...
01:24Drug Toxicity: Dose-Dependent Reactions
Drug toxicities can be stratified into pharmacological, pathological, or genotoxic based on their mechanisms. The incidence and severity of these toxicities generally increase with the drug's concentration in the body and exposure time.Pharmacological toxicity is evident when the therapeutic effects of drugs overshoot into adverse reactions in a predictable, dose-dependent manner. Central nervous system (CNS) depression from barbiturates is a classic example, with effects escalating from...
01:28Pharmacokinetic–Pharmacodynamic Relationship: Dose to Pharmacological Effect
A drug’s dosage and pharmacokinetic properties determine how quickly it acts, how intense its effects are, and how long it lasts. Higher doses increase drug concentration at receptor sites, producing a hyperbolic curve when pharmacologic response is plotted against drug dose. Converting this scale to a log-linear format results in a sigmoidal curve, better representing dose–response relationships.For drugs following a one-compartment model, the pharmacologic response is directly proportional to...
01:08Effect of Hepatic Disease on Pharmacokinetics: Dose Adjustments Due to Hepatic Impairment
Hepatic impairment, characterized by decreased liver function, does not uniformly mandate adjustments in drug dosage. Whether dosage modifications are necessary depends on various factors related to the drug's metabolism and elimination pathways. If a drug is primarily excreted via the kidneys and bypasses significant hepatic processing, if it undergoes minimal metabolic transformation in the liver, or if it is volatile and primarily expelled through the lungs, dose adjustments may not be...
01:29Therapeutic Drug Monitoring: Affecting Factors
Therapeutic Drug Monitoring (TDM) is the clinical practice of measuring specific drug levels in a patient's blood or body tissues to manage and optimize therapy. TDM is crucial for drugs with narrow therapeutic windows, like warfarin and phenytoin, where incorrect doses can lead to treatment failure or severe side effects. This monitoring ensures the dosage administered is within a safe and effective range. The factors affecting therapeutic drug monitoring include:Patient-Specific Factors:a.
01:30Drug toxicity: Drug–Drug Interaction
Drug–drug interactions can precipitate toxicity through multiple mechanisms. Absorption interactions alter how drugs enter the body, exemplified when ranitidine increases the absorption of basic drugs, while cholestyramine decreases the levels of propranolol. Protein binding interactions occur when drugs share the same binding sites on plasma proteins. Drugs like aspirin and warfarin, when bound in excess, can lead to increased free drug concentrations, enhancing the potential for...