Bezafibrate induced rhabdomyolysis

Possibility of Multiple Drug-Drug Interactions in Patients Treated with Statins: Analysis of Data from the Japanese Adverse Drug Event Report (JADER) Database and Verification by Animal Experiments

Adverse drug events due to drug-drug interactions can be prevented by avoiding concomitant use of causative drugs; therefore, it is important to understand drug combinations that cause drug-drug interactions. Although many attempts to identify drug-drug interactions from real-world databases such as spontaneous reporting systems have been performed, little is known about drug-drug interactions caused by three or more drugs in polypharmacy, i.e., multiple drug-drug interactions. Therefore, we attempted to detect multiple drug-drug interactions using decision tree analysis using the Japanese Adverse Drug Event Report (JADER) database, a Japanese spontaneous reporting system. First, we used decision tree analysis to detect drug combinations that increase the risk of rhabdomyolysis in cases registered in the JADER database that used six statins. Next, the risk of three or more drug combinations that significantly increased the risk of rhabdomyolysis was validated with in vivo experiments in rats. The analysis identified a multiple drug-drug interaction signal only for pitavastatin. The reporting rate of rhabdomyolysis for pitavastatin in the JADER database was 0.09, and it increased to 0.16 in combination with allopurinol. Furthermore, the rate was even higher (0.40) in combination with valsartan. Additionally, necrosis of leg muscles was observed in some rats simultaneously treated with these three drugs, and their creatine kinase and myoglobin levels were elevated. The combination of pitavastatin, allopurinol, and valsartan should be treated with caution as a multiple drug-drug interaction. Since multiple drug-drug interactions were detected with decision tree analysis and the increased risk was verified in animal experiments, decision tree analysis is considered to be an effective method for detecting multiple drug-drug interactions.

Bezafibrate activation of PPAR drives disturbances in mitochondrial redox bioenergetics and decreases the viability of cells from patients with VLCAD deficiency

Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is the most common inborn long-chain fatty acid oxidation (FAO) disorder. VLCAD deficiency is characterized by distinct phenotypes. The severe phenotypes are potentially life-threatening and affect the heart or liver, with a comparatively milder phenotype characterized by myopathic symptoms. There is an unmet clinical need for effective treatment options for the myopathic phenotype. The molecular mechanisms driving the gradual decrease in mitochondrial function and associated alterations of muscle fibers are unclear. The peroxisome proliferator-activated receptor (PPAR) pan-agonist bezafibrate is a potent modulator of FAO and multiple other mitochondrial functions and has been proposed as a potential medication for myopathic cases of long-chain FAO disorders. In vitro experiments have demonstrated the ability of bezafibrate to increase VLCAD expression and activity. However, the outcome of small-scale clinical trials has been controversial. We found VLCAD deficient patient fibroblasts to have an increased oxidative stress burden and deranged mitochondrial bioenergetic capacity, compared to controls. Applying heat stress under fasting conditions to bezafibrate pretreated patient cells, caused a marked further increase of mitochondrial superoxide levels. Patient cells failed to maintain levels of the essential thiol peptide antioxidant glutathione and experienced a decrease in cellular viability. Our findings indicate that chronic PPAR activation is a plausible initiator of long-term pathogenesis in VLCAD deficiency. Our findings further implicate disruption of redox homeostasis as a key pathogenic mechanism in VLCAD deficiency and support the notion that a deranged thiol metabolism might be an important pathogenic factor in VLCAD deficiency.

Fenofibrate monotherapy-induced rhabdomyolysis in a patient with post-pancreatitis diabetes mellitus: A rare case report and a review of the literature

RATIONALE

Fibrates are widely used to control hypertriglyceridemia and mixed dyslipidemia alone or in combination with statins. These drugs have rare, but severe and potentially vital adverse reactions of rhabdomyolysis and secondary acute renal failure (ARF). The objective of this article is to analyze this adverse effect of fibrates and ensure the safety of drug use.

PATIENT CONCERNS

We report a case of rhabdomyolysis and ARF due to fenofibrate monotherapy in a 68-year-old female with post-pancreatitis diabetes mellitus and review reported cases of rhabdomyolysis correlated with fibrates monotherapy.

DIAGNOSIS

The patient was diagnosed with rhabdomyolysis associated with fenofibrate monotherapy as confirmed by symptoms of fatigue and muscle pain, and elevated levels of myoglobin and creatine kinase.

INTERVENTIONS

Fenofibrate therapy was discontinued. Moreover, intravenous fluids, urinary alkalization, and diuretic were performed.

OUTCOMES

The symptoms were completely relieved, and relevant laboratory indexes returned to normal range during follow-up.

LESSONS

Physicians should be aware of the side effect of rhabdomyolysis of fibrates, and patients should also be informed about this potential side effect, especially for patients with high-risk factors. A favorable outcome can be achieved by timely diagnosis and prompt treatment.

Safety considerations with fibrate therapy

Fibrates are an important class of drugs for the management of dyslipidemia. This class of drugs is generally well tolerated but is infrequently associated with several safety issues. Fibrates, most likely by an effect mediated by peroxisome proliferator-activated receptor-alpha, may reversibly increase creatinine and homocysteine but are not associated with an increased risk for renal failure in clinical trials. Fibrates are associated with a slightly increased risk (<1.0%) for myopathy, cholelithiasis, and venous thrombosis. In clinical trials, patients without elevated triglycerides and/or low high-density lipoprotein cholesterol (HDL) levels, fibrates are associated with an increase in noncardiovascular mortality. In combination with statins, gemfibrozil generally should be avoided. The preferred option is fenofibrate, which is not associated with an inhibition of statin metabolism. Clinicians are advised to measure serum creatinine before fibrate use and adjust the dose accordingly for renal impairment. Routine monitoring of creatinine is not required, but if a patient has a clinically important increase in creatinine, and other potential causes of creatinine increase have been excluded, consideration should be given to discontinuing fibrate therapy or reducing the dose.

Fibrates in combination with statins in the management of dyslipidemia

While elevated low-density lipoprotein cholesterol is the primary target of hypercholesterolemia treatment, high triglycerides and low high-density lipoprotein cholesterol are also important targets for therapy. Correcting these lipid abnormalities should be an integral part of therapy in hypertensive individuals. Medications such as the fibrates are effective and well tolerated for reducing triglycerides and increasing high-density lipoprotein cholesterol, and their use has resulted in a reduction in cardiovascular events. Fibrates are also recommended as adjunct therapy for patients receiving statins whose low-density lipoprotein cholesterol or non-high-density lipoprotein cholesterol is not reduced to goal levels. The combination of a statin and a fibrate may, however, raise the risk of myopathy and rhabdomyolysis. Gemfibrozil, one of the fibrates, but not fenofibrate, interferes with statin glucuronidation, which may increase the risk of myopathy due to elevations in statin serum levels. This may at least partially explain the lower incidence of myopathy with fenofibrate compared with gemfibrozil when combined with statins. Combination therapy with a fibrate and a statin is a potentially useful therapy for patients with atherogenic lipid profiles, for which fenofibrate appears to be a more appropriate choice due to less myopathic potential.

The Toxicology of Ligands for Peroxisome Proliferator-Activated Receptors (PPAR)

Peroxisome proliferator-activated receptors (PPARs) are ligand activated transcription factors that modulate target gene expression in response to endogenous and exogenous ligands. Ligands for the PPARs have been widely developed for the treatment of various diseases including dyslipidemias and diabetes. While targeting selective receptor activation is an established therapeutic approach for the treatment of various diseases, a variety of toxicities are known to occur in response to ligand administration. Whether PPAR ligands produce toxicity via a receptor-dependent and/or off-target-mediated mechanism(s) is not always known. Extrapolation of data derived from animal models and/or in vitro models, to humans, is also questionable. The different toxicities and mechanisms associated with administration of ligands for the three PPARs will be discussed, and important data gaps that could increase our current understanding of how PPAR ligands lead to toxicity will be highlighted.

Mizoribine-induced Rhabdomyolysis in a Rheumatoid Arthritis Patient Receiving Bezafibrate Treatment

Bezafibrate, one of fibric acid derivatives, is widely used to treat hypertriglyceridemia and diabetic dyslipidemia. Fibric acid derivatives are known to induce rhabdomyolysis as a side effect, especially when given to patients with renal dysfunction. Mizoribine, an imidazole nucleoside, is used as an immunosuppressive agent. Here, we present a case of a patient with rheumatoid arthritis who developed rhabdomyolysis while undergoing treatment with mizoribine concomitantly with bezafibrate. Drug-induced rhabdomyolysis was suspected and bezafibrate and mizoribine were discontinued, and the patient was treated with hydration. The patient's symptoms rapidly disappeared and abnormalities of blood and urine test findings also improved to normal levels within 1 week. When prescribing fibrates to patients with high risk of renal damage, caution should be exercised regarding interactions with other drugs and the potential for inducing rhabdomyolysis.

Acute renal failure after cardiopulmonary bypass: a possible association with drugs of the fibrate group

BACKGROUND

Renal failure is a recognized, but infrequent, complication following cardiac surgery. The causes for this condition are multifactorial, and a major concern is that the occurrence of postoperative acute renal failure is still associated with a high mortality rate.

METHODS AND MATERIALS

We report unexpected acute renal failure occurring in 4 patients after uncomplicated cardiac surgery. Each patient was taking a fibric acid derivative at the time of surgery. Renal failure occurred rapidly within 3 days of surgery and was associated with increased concentrations of skeletal muscle-derived creatine kinase (CK). One patient developed myoglobinuria, and another developed a malignant hyperthermia-like syndrome.

CONCLUSIONS

These cases show that patients receiving lipid lowering medications could be at higher risk of developing acute renal failure after cardiac surgery. This association merits careful evaluation in large prospective studies and, if proved, would suggest that patients taking either statins or fibrates should discontinue doing so before cardiac surgery.

Bezafibrate. An update of its pharmacology and use in the management of dyslipidaemia

The lipid-modifying profile of bezafibrate is characterised by marked decreases in elevated triglyceride levels, increases in high density lipoprotein (HDL) cholesterol levels and decreases in total and low density lipoprotein (LDL) cholesterol levels. Bezafibrate also reduces elevated levels of lipoprotein(a) [Lp(a)] and fibrinogen, which are independent cardiovascular risk factors. Bezafibrate is effective in most types of primary and secondary dyslipidaemia. It is of greatest benefit in conditions featuring hypertriglyceridaemia and/or HDL cholesterol deficiency. This is particularly true for patients with diabetes mellitus, notably those with non-insulin-dependent diabetes mellitus (NIDDM) who are also likely to have increased fibrinogen levels. In the limited comparisons available, there appear to be few consistent differences in lipid-modifying effects between bezafibrate and other fibrates. Compared with HMG-CoA reductase inhibitors, bezafibrate causes larger changes in triglyceride and, in general, HDL cholesterol levels, and has a lesser influence on LDL and total cholesterol levels. These differences are advantageous when bezafibrate and HMG-CoA reductase inhibitors are used as combined therapy in patients with severe dyslipidaemia unresponsive to either modality alone. The combination of bezafibrate plus an HMG-CoA reductase inhibitor in clinical trials has not led to the predicted increase in myalgia. Indeed, bezafibrate is generally free of serious unwanted effects: rhabdomyolysis is rare and has occurred mainly in patients with renal dysfunction given excessive dosages. Other patient groups in whom bezafibrate has improved serum lipid profiles are those with isolated HDL cholesterol deficiency, dyslipidaemia secondary to renal insufficiency, and following cardiac surgery or other procedures. However, data for these indications are not extensive. Evidence is now available to show a beneficial effect of bezafibrate on retarding atherosclerotic processes and in reducing risk of coronary heart disease. The 5-year Bezafibrate Coronary Atherosclerosis Intervention Trial (BECAIT) in young male survivors of myocardial infarction demonstrated a smaller decrease in luminal diameter and a reduction in coronary events with bezafibrate compared with placebo. The Bezafibrate Infarction Prevention (BIP) study is expected to provide mortality data which is currently lacking for bezafibrate. In conclusion, bezafibrate is a useful and well-tolerated lipid-modifying agent in the management of primary and secondary dyslipidaemia. It has particularly beneficial effects in patients with hypertriglyceridaemia and/or low HDL cholesterol levels, and reduces fibrinogen levels. Together with its ability to sustain or improve glycaemic control, these properties make it a logical choice for treating patients with diabetes mellitus and dyslipidaemia. Additionally, the drug may be of value as combination therapy in patients with severe dyslipidaemia. Importantly, there is evidence that the drug can slow the atherosclerotic process and reduce cardiovascular morbidity. The ongoing BIP secondary intervention study and other investigations will help clarify the effects of bezafibrate on cardiovascular mortality and morbidity.