Differential effects on renal function and glucose metabolism of renal dependent bezafibrate and non-renal dependent pemafibrate in patients with hypertriglyceridemia

OBJECTIVE

Among fibrates as triglyceride-lowering agents, bezafibrate and fenofibrate are predominantly renally excreted, while pemafibrate is mainly hepatically metabolized and biliary excreted. To elucidate possible different properties among fibrates, this retrospective observational study examined the changes in clinical laboratory parameters, including indices of renal function and glucose metabolism, in cases of switching from bezafibrate to pemafibrate.

MATERIALS AND METHODS

In 93 patients with hypertriglyceridemia, the average values of laboratory parameters including serum creatinine, estimated glomerular filtration rate (eGFR), plasma glucose, and hemoglobin A1c on respective two occasions before and after switching from bezafibrate to pemafibrate were evaluated.

RESULTS

Triglycerides, low-density and high-density lipoprotein cholesterol, creatine kinase, and uric acid did not change before and after switching from bezafibrate to pemafibrate. Serum creatinine significantly decreased and eGFR significantly increased after switching from bezafibrate to pemafibrate (p < 0.001, respectively). Plasma glucose tended to increase (p = 0.070) and hemoglobin A1c significantly increased (p < 0.001) after switching to pemafibrate. The degrees of changes in creatinine, eGFR, glucose, and hemoglobin A1c before and after drug switching were not affected by the presence or absence of coexisting disease, and with or without drug treatment including statin and renin-angiotensin system inhibitor.

CONCLUSION

Our findings indicate that switching from bezafibrate to pemafibrate produces a significant decrease in serum creatinine and increases in eGFR and hemoglobin A1c in patients with hypertriglyceridemia, suggesting that the effects on renal function and glucose metabolism differ among fibrates.

Combination treatment with statins and bezafibrate induces myotoxicity via inhibition of geranylgeranyl pyrophosphate biosynthesis and Rho activation in L6 myoblasts and myotube cells

Statins and fibrates are frequently used to treat hyperlipidemia; however, these drugs may have adverse effects such as rhabdomyolysis. The incidence of rhabdomyolysis due to fibrates and statins is low (0.0028-0.0096%) when administered as monotherapy, however it increases to 0.015-0.021% when the drugs are used in combination. The mechanism underlying myotoxicity induced by the combination of statins and fibrates is yet unclear. Here, we investigated the mechanisms underlying induced myotoxicity in rat myoblasts L6 and differentiated L6 cells (myotubes) using a combination of statins and fibrates. We found that cell death induced by a combination of fluvastatin or simvastatin with bezafibrate or fenofibrate in L6 myoblasts and myotubes was mediated by inhibition of geranylgeranyl pyrophosphate (GGPP) production. Additionally, the drug combination inhibited Rho activation in L6 myoblasts and myotube cells. In L6 myoblasts, the combination of statins and bezafibrate enhanced p27 expression and induced G1 arrest and apoptosis. Furthermore, combined treatment suppressed Akt activation and enhanced Bim expression in L6 myotubes but did not affect extracellular regulated protein kinase 1/2 activation. These results suggested that combined administration of statins and fibrates induced death of L6 myoblasts and myotube cells by inhibiting GGPP biosynthesis and Rho pathway activation. Supplementation with GGPP may be therapeutically beneficial for preventing myotoxicity associated with combined statin and fibrates treatment.

Safety of fibrates in cholestatic liver diseases

BACKGROUND AND AIM

Off-label use of fibrates in patients with cholestatic liver diseases results in improved biochemical parameters and pruritus; however, their safety in this population has been a concern. This study summarizes safety data for fibrates when used for treatment of cholestatic liver diseases.

METHODS

A systematic review of published studies evaluating the use of fibrates for treatment of primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) was performed. Electronic databases were searched up to December 2019 for published studies evaluating treatment outcomes associated to fibrates for these 2 diseases.

RESULTS

A total of 37 studies were identified, including 31 for PBC and 6 for PSC, with a total of 1107 unique patients treated with fibrates ± ursodeoxycholic acid (UDCA). Most studies evaluated fenofibrate and bezafibrate, and only 1 study evaluated pemafibrate. There were no studies evaluating gemfibrozil or clofibrate. The most commonly reported adverse events (AEs) were gastrointestinal and musculoskeletal. Elevations of aminotransferases and serum creatinine were reported more commonly in patients treated with UDCA plus fibrates versus UDCA monotherapy.

CONCLUSIONS

Fibrates appear to be safe and well tolerated in patients with PBC, with a low frequency of AEs. There are scarce data about the safety of these agents for treatment of PSC.

A Placebo-Controlled Trial of Bezafibrate in Primary Biliary Cholangitis

BACKGROUND

Patients with primary biliary cholangitis who have an inadequate response to therapy with ursodeoxycholic acid are at high risk for disease progression. Fibrates, which are agonists of peroxisome proliferator-activated receptors, in combination with ursodeoxycholic acid, have shown potential benefit in patients with this condition.

METHODS

In this 24-month, double-blind, placebo-controlled, phase 3 trial, we randomly assigned 100 patients who had had an inadequate response to ursodeoxycholic acid according to the Paris 2 criteria to receive bezafibrate at a daily dose of 400 mg (50 patients), or placebo (50 patients), in addition to continued treatment with ursodeoxycholic acid. The primary outcome was a complete biochemical response, which was defined as normal levels of total bilirubin, alkaline phosphatase, aminotransferases, and albumin, as well as a normal prothrombin index (a derived measure of prothrombin time), at 24 months.

RESULTS

The primary outcome occurred in 31% of the patients assigned to bezafibrate and in 0% assigned to placebo (difference, 31 percentage points; 95% confidence interval, 10 to 50; P<0.001). Normal levels of alkaline phosphatase were observed in 67% of the patients in the bezafibrate group and in 2% in the placebo group. Results regarding changes in pruritus, fatigue, and noninvasive measures of liver fibrosis, including liver stiffness and Enhanced Liver Fibrosis score, were consistent with the results of the primary outcome. Two patients in each group had complications from end-stage liver disease. The creatinine level increased 5% from baseline in the bezafibrate group and decreased 3% in the placebo group. Myalgia occurred in 20% of the patients in the bezafibrate group and in 10% in the placebo group.

CONCLUSIONS

Among patients with primary biliary cholangitis who had had an inadequate response to ursodeoxycholic acid alone, treatment with bezafibrate in addition to ursodeoxycholic acid resulted in a rate of complete biochemical response that was significantly higher than the rate with placebo and ursodeoxycholic acid therapy. (Funded by Programme Hospitalier de Recherche Clinique and Arrow Génériques; BEZURSO ClinicalTrials.gov number, NCT01654731 .).

Fibrates for the treatment of cholestatic itch (FITCH): study protocol for a randomized controlled trial

BACKGROUND

Pruritus (itch) is a frequent, burdensome and difficult-to-treat symptom in patients with cholestasis. Fibrates are currently under investigation for the treatment of primary biliary cholangitis in patients with a suboptimal response to ursodeoxycholic acid. Moreover, there is empirical evidence for a possible antipruritic effect. We aim to prove this in a randomized controlled trial, including patients with cholestatic liver diseases other than primary biliary cholangitis that are accompanied by pruritus.

METHODS

A multicenter investigator-initiated, double-blind, randomized placebo-controlled trial to evaluate the effect of bezafibrate on cholestatic pruritus in 84 adult patients with primary biliary cholangitis or primary/secondary sclerosing cholangitis. Primary outcome is the proportion of patients with a reduction of itch intensity of 50% or more (measured on a Visual Analog Scale) after 21 days of treatment with bezafibrate 400 mg qid or placebo. Secondary outcomes include the effect of bezafibrate on a five-dimensional itch score, liver disease-specific quality of life, serum liver tests and autotaxin activity. Safety will be evaluated through serum parameters for kidney function and rhabdomyolysis as well as precise recording of (serious) adverse events. We provide a schematic overview of the study protocol and describe the methods used to recruit and randomize patients, collect and handle data and perform statistical analyses.

DISCUSSION

Given its favorable safety profile and anticholestatic properties, bezafibrate may become the new first-line treatment option for treating cholestatic pruritus.

TRIAL REGISTRATION

Netherlands Trial Register, ID: NCT02701166 . Registered on 2 March 2016; Netherlands Trial Register, ID: NTR5436 . Registered on 3 August 2015.

Systematic review and meta-analysis: bezafibrate in patients with primary biliary cirrhosis

BACKGROUND AND AIM

Ursodeoxycholic acid (UDCA) is the standard treatment for primary biliary cirrhosis (PBC), but not all cases respond well. Evidence has shown that combination therapy of UDCA with bezafibrate significantly improved liver function. A meta-analysis was performed to assess the efficacy and safety of UDCA and bezafibrate combination therapy in the treatment of PBC.

RESULTS

Nine trials, with a total of 269 patients, were included in the analysis. The bias risk of these trials was high. Compared with UDCA alone, the combination with bezafibrate improved the Mayo risk score (mean difference [MD], 0.60; 95% confidence interval [CI], 0.25-0.95; P=0.0008) and liver biochemistry: alkaline phosphatase (MD, -238.21 IU/L; 95% CI, -280.83 to -195.60; P<0.00001); gamma-glutamyltransferase (MD, -38.23 IU/L; 95% CI, -50.16 to -25.85; P<0.00001); immunoglobulin M (MD, -128.63 IU/L; 95% CI, -151.55 to -105.71; P<0.00001); bilirubin (MD, -0.20 mg/dL; 95% CI, -0.33 to -0.07; P=0.002); triglycerides (MD, -26.84 mg/dL; 95% CI, -36.51 to -17.17; P<0.0001); total cholesterol (MD, -21.58 mg/dL; 95% CI, -30.81 to -12.34; P<0.0001), and serum alanine aminotransferase (MD, -10.24 IU/L; 95% CI, -12.65 to -78.5; P<0.00001). However, combination therapy showed no significant differences in the incidence of all-cause mortality or pruritus, and may have resulted in more adverse events (risk ratio [RR], 0.22; 95% CI, 0.07-0.67; P=0.008).

CONCLUSION

Combination therapy improved liver biochemistry and the prognosis of PBC, but did not improve clinical symptoms or incidence of death. Attention should be paid to adverse events when using bezafibrate.

Long-term bezafibrate treatment improves skin and spleen phenotypes of the mtDNA mutator mouse

Pharmacological agents, such as bezafibrate, that activate peroxisome proliferator-activated receptors (PPARs) and PPAR γ coactivator-1α (PGC-1α) pathways have been shown to improve mitochondrial function and energy metabolism. The mitochondrial DNA (mtDNA) mutator mouse is a mouse model of aging that harbors a proofreading-deficient mtDNA polymerase γ. These mice develop many features of premature aging including hair loss, anemia, osteoporosis, sarcopenia and decreased lifespan. They also have increased mtDNA mutations and marked mitochondrial dysfunction. We found that mutator mice treated with bezafibrate for 8-months had delayed hair loss and improved skin and spleen aging-like phenotypes. Although we observed an increase in markers of fatty acid oxidation in these tissues, we did not detect a generalized increase in mitochondrial markers. On the other hand, there were no improvements in muscle function or lifespan of the mutator mouse, which we attributed to the rodent-specific hepatomegaly associated with fibrate treatment. These results showed that despite its secondary effects in rodent’s liver, bezafibrate was able to improve some of the aging phenotypes in the mutator mouse. Because the associated hepatomegaly is not observed in primates, long-term bezafibrate treatment in humans could have beneficial effects on tissues undergoing chronic bioenergetic-related degeneration.

Bezafibrate for primary biliary cirrhosis

BACKGROUND

Treatment of primary biliary cirrhosis is complicated. There are studies suggesting that bezafibrate, alone or in combination with ursodeoxycholic acid (UDCA), is effective in the treatment of primary biliary cirrhosis, but no systematic review has summarised the evidence yet.

OBJECTIVES

To assess the beneficial and harmful effects of bezafibrate in patients with primary biliary cirrhosis.

SEARCH METHODS

The Cochrane Hepato-Biliary Group Controlled Trials Register, The Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, LILACS, Clinicaltrials.gov, the WHO International Clinical Trials Registry Platform, and full text searches were conducted until November 2011. The searches in Chinese Bio-medical Literature Database, China Network Knowledge Information, Chinese Science Journal Database, Chinese Medical Citation Index, Wanfang Database, and full text searches were conducted until January 2011. Manufacturers and authors were contacted.

SELECTION CRITERIA

All randomised clinical trials comparing bezafibrate at any dose or regimen in patients with primary biliary cirrhosis with placebo or no intervention, or with another drug. Any concomitant interventions were allowed if received equally by all treatment groups in a trial.

DATA COLLECTION AND ANALYSIS

Two authors extracted data. RevMan Analysis was used for statistical analysis of dichotomous data with risk ratio (RR) or risk difference (RD), and of continuous data with mean difference (MD), both with 95% confidence intervals (CI). Methodological domains were used to assess risk of systematic errors (bias). Trial sequential analysis was used to control for random errors (play of chance).

MAIN RESULTS

Six trials with 151 Japanese patients were included. All trials had high risk of bias. Four trials compared bezafibrate plus UDCA with no intervention plus UDCA (referenced as bezafibrate versus no intervention in the remaining text), and two trials compared bezafibrate with UDCA. No patient died and no patient developed liver-related complications in any of the included trials. Bezafibrate was without significant effects on the occurrence of adverse events compared with no intervention (5/32 (16%) versus 0/28 (0%)) (RR 5.40, 95% CI 0.69 to 42.32; 3 trials with 60 patients; I² = 0%) or with UDCA (2/32 (6%) versus 0/37 (0%)) (RR 6.19, 95% CI 0.31 to 122.05; 2 trials with 69 patients; I² = 0%). Bezafibrate significantly decreased the activity of serum alkaline phosphatases compared with no intervention (MD -186.04 U/L, 95% CI -249.03 to -123.04; 4 trials with 79 patients; I² = 34%) and when compared with UDCA (MD -162.90 U/L, 95% CI -199.68 to -126.12; 2 trials with 48 patients; I² = 0%). These results were supported by trial sequential analyses. Bezafibrate compared with no intervention significantly decreased plasma immunoglobulin M (MD -164.00 mg/dl, 95% CI -259.47 to -68.53; 3 trials with 50 patients; I² = 46%) and serum bilirubin concentration (MD -0.19 mg/dl, 95% CI -0.38 to -0.00; 2 trials with 34 patients; I² = 0%). However, the latter two results were not supported by trial sequential analyses. Bezafibrate compared with no intervention had no significant effect on the activity of serum gamma-glutamyltransferase (MD -1.22 U/L, 95% CI -11.97 to 9.52; 4 trials with 79 patients; I² = 42%) and serum alanine aminotransferase (MD -5.61 U/L, 95% CI -24.50 to 13.27; 2 trials with 35 patients; I² = 34%). Bezafibrate compared with UDCA had no significant effect on the activity of serum gamma-glutamyltransferase (MD 38.44 U/L, 95% CI -180.67 to 257.55; 2 trials with 49 patients; I² = 89%), serum alanine aminotransferase (MD -2.34 U/L, 95% CI -34.73 to 30.06; 2 trials with 49 patients; I² = 95%), and plasma immunoglobulin M concentration (MD -20.23 mg/dl, 95% CI -218.71 to 178.25; 2 trials with 41 patients; I² = 90%) in random-effects model meta-analyses, but bezafibrate significantly decreased the activity of serum gamma-glutamyltransferase (MD -58.18, 95% CI -76.49 to -39.88; 2 trials with 49 patients; I² = 89%), serum alanine aminotransferase (MD -13.94, 95% CI -18.78 to -9.09; 2 trials with 49 patients; I² = 95%), and plasma immunoglobulin M concentration (MD -99.90, 95% CI -130.72 to -69.07; 2 trials with 41 patients; I² = 90%) in fixed-effect model meta-analyses. One patient had bezafibrate withdrawn due to an adverse event compared to no intervention (RD 0.03, 95% CI -0.09 to 0.16; 2 trials with 60 patients; I² = 0%).

AUTHORS' CONCLUSIONS

This systematic review did not demonstrate any effect of bezafibrate versus no intervention on mortality, liver-related morbidity, adverse events, and pruritus in patients with primary biliary cirrhosis. Furthermore, we found no significant effects of bezafibrate on mortality, liver-related morbidity, or adverse events when compared with ursodeoxycholic acid, None of the trials assessed quality of life or fatigue. The data seem to indicate a possible positive intervention effect of bezafibrate on some liver biochemistry measures compared with the control group, but the observed effects could be due to systematic errors or random errors. We need more randomised clinical trials on the effects of bezafibrate on primary biliary cirrhosis with low risks of systematic errors and random errors.

PET/CT quantitation of the effect of patient-related factors on cardiac 18F-FDG uptake

The effect of multiple patient-related factors on the degree of cardiac 18F-FDG uptake was assessed.

METHODS

Five hundred four consecutive patients undergoing routine 18F-FDG PET/CT studies completed a clinical questionnaire. 18F-FDG uptake was measured as the mean standardized uptake value within the heart delineated on the CT component of the study. Univariate and multivariate analyses assessed the influence of 51 clinical factors on cardiac 18F-FDG uptake.

RESULTS

On both multivariate and univariate analyses, cardiac 18F-FDG uptake was significantly lower in diabetics and in patients receiving bezafibrate or levothyroxine. Cardiac 18F-FDG uptake was significantly higher in men, patients younger than 30 y old, fasting duration of <5 h, patients with heart failure, and those receiving benzodiazepines.

CONCLUSION

Cardiac 18F-FDG uptake was lower in patients receiving bezafibrate and levothyroxine and higher in patients receiving benzodiazepines. If further confirmed by prospectively designed studies, manipulation of these drugs may represent tools for optimized PET/CT imaging.

Effect of rosuvastatin 5-20mg on triglycerides and other lipid parameters in Japanese patients with hypertriglyceridemia

To evaluate the potential dose effect of rosuvastatin on triglyceride (TG) levels in Japanese hypertriglyceridemic patients, we randomized 154 patients with TG levels of >or=200 and <800 mg/dL to 8 weeks of treatment with rosuvastatin 5, 10 or 20mg once daily; bezafibrate 200mg twice daily; or placebo. Compared with placebo, TG was reduced by 30.1% with rosuvastatin 5mg, 30.1% with 10mg and 32.3% with 20mg (all p<or=0.0001), with no evidence of a dose effect. Changes in TG were evident after 2 weeks of treatment and maintained thereafter. In a benchmark comparison, rosuvastatin across its dose range reduced TG by 29.1-31.1% from baseline versus 45.4% for bezafibrate. Compared with bezafibrate, rosuvastatin was superior with respect to changes in non-high-density lipoprotein cholesterol (non-HDL-C, -36.8 to -44.3% for rosuvastatin versus -2.0% for bezafibrate), low-density lipoprotein cholesterol (-31.9 to -41.0% versus +29.3%), total cholesterol (-27.1 to -33.3% versus +2.1%), although smaller improvements in HDL-C (12.4-16.7% versus 19.6%) were observed. Rosuvastatin also produced superior dose-related decreases in median high-sensitivity C-reactive protein (22.9-38.5%). Treatment was well tolerated in both rosuvastatin and bezafibrate patients, with clinically important increases in alanine aminotransferase being rare, no adverse effect on renal function being observed and no cases of myopathy or rhabdomyolysis being reported. The current study does not suggest a dose-related effect of rosuvastatin in lowering TG in hypertriglyceridemic Japanese patients, although dose-related improvements in other elements of the atherogenic lipid profile were observed.

Effects of bezafibrate on HDL2/HDL3 ratio in postmenopausal hypertriglyceridemic women

The short-term effects of bezafibrate on high-density lipoprotein cholesterol quality and triglyceride-rich lipoprotein metabolism in 186 postmenopausal hypertriglyceridemic women were investigated. Patients were randomized to an untreated group and to bezafibrate (400 mg/d) for 6 months. Fasting lipid concentrations, high-density lipoprotein 2, and high-density lipoprotein 3 levels were measured at baseline and after 3 and 6 months. At 3 months, bezafibrate had significantly decreased mean serum triglycerides and remnant-like particle cholesterol levels (105.7 +/- 43.4 mg/dL and 5.33 +/- 2.1 mg/dL, P < .001, respectively) from baseline values (232.5 +/- 63.9 mg/dL and 9.69 +/- 3.8 mg/dL, respectively). It also maintained lower total cholesterol, low-density lipoprotein cholesterol, triglycerides, and remnant-like particle cholesterol concentrations to 6 months. After 3 months, it significantly increased mean serum high-density lipoprotein cholesterol (55.1 +/- 14.7 vs 64.8 +/- 12.1 mg/dL; P < .0001) and maintained higher high-density lipoprotein cholesterol at 6 months. The high-density lipoprotein 2-high-density lipoprotein 3 ratio was decreased after 3 months of therapy with bezafibrate (2.13 +/- 0.68) from the baseline (2.42 +/- 0.71) (P < .01).

Fish oil increases bile acid synthesis in male patients with hypertriglyceridemia

Fibrates are drugs of choice in patients with hypertriglyceridemia (HTG), but may increase the risk for gallstones by decreasing bile acid synthesis. Fish oil might be a therapeutic alternative, but its effect on bile acid metabolism in humans is unknown. We compared the effects of triglyceride-lowering therapy by fish oil or bezafibrate on cholesterol synthesis and bile acid metabolism in HTG. Cholesterol synthesis, bile acid pool sizes, and synthesis rates were compared between 9 male HTG patients and 10 normolipidemic controls matched for age, sex, and BMI. Effects of bezafibrate or fish oil were studied only in HTG patients in a randomized crossover trial. Patients had 14-fold higher serum triglyceride concentrations and greater cholesterol synthesis, as indicated by a 107% higher ratio of serum lathosterol to cholesterol (P < 0.01) than controls. The groups did not differ in bile acid metabolism. Both bezafibrate and fish oil reduced serum TG concentration (-68 and -51% vs. baseline, respectively). Compared with baseline, bezafibrate therapy was associated with reduced cholesterol synthesis (-25%, P = 0.009) without changes in bile acid synthesis rate and pool size. In contrast, fish oil increased bile acid synthesis (+31% vs. baseline, P = 0.07 and +53% vs. bezafibrate, P = 0.02) and altered bile acid distribution, as reflected by an increased ratio of the cholic acid (CA) synthesis rate to the chenodeoxycholic acid (CDCA) synthesis rate (+35% vs baseline, P = 0.05 and + 32% vs bezafibrate, P = 0.07) without effects on bile acid pool size or cholesterol synthesis. In conclusion, cholesterol synthesis is greater in HTG patients than in controls, whereas bile acid synthesis does not differ. Bezafibrate and fish oil have similar triglyceride-lowering capacities, but distinct effects on cholesterol synthesis. Bile acid synthesis is increased by fish oil, but not by bezafibrate therapy.

Dual and pan-peroxisome proliferator-activated receptors (PPAR) co-agonism: the bezafibrate lessons

There are three peroxisome proliferator-activated receptors (PPARs) subtypes which are commonly designated PPAR alpha, PPAR gamma and PPAR beta/delta. PPAR alpha activation increases high density lipoprotein (HDL) cholesterol synthesis, stimulates "reverse" cholesterol transport and reduces triglycerides. PPAR gamma activation results in insulin sensitization and antidiabetic action. Until recently, the biological role of PPAR beta/delta remained unclear. However, treatment of obese animals by specific PPAR delta agonists results in normalization of metabolic parameters and reduction of adiposity. Combined treatments with PPAR gamma and alpha agonists may potentially improve insulin resistance and alleviate atherogenic dyslipidemia, whereas PPAR delta properties may prevent the development of overweight which typically accompanies "pure" PPAR gamma ligands. The new generation of dual-action PPARs – the glitazars, which target PPAR-gamma and PPAR-alpha (like muraglitazar and tesaglitazar) are on deck in late-stage clinical trials and may be effective in reducing cardiovascular risk, but their long-term clinical effects are still unknown. A number of glitazars have presented problems at a late stage of clinical trials because of serious side-effects (including ragaglitazar and farglitazar). The old and well known lipid-lowering fibric acid derivative bezafibrate is the first clinically tested pan – (alpha, beta/delta, gamma) PPAR activator. It is the only pan-PPAR activator with more than a quarter of a century of therapeutic experience with a good safety profile. Therefore, bezafibrate could be considered (indeed, as a "post hoc" understanding) as an "archetype" of a clinically tested pan-PPAR ligand. Bezafibrate leads to considerable raising of HDL cholesterol and reduces triglycerides, improves insulin sensitivity and reduces blood glucose level, significantly lowering the incidence of cardiovascular events and new diabetes in patients with features of metabolic syndrome. Clinical evidences obtained from bezafibrate-based studies strongly support the concept of pan-PPAR therapeutic approach to conditions which comprise the metabolic syndrome. However, from a biochemical point of view, bezafibrate is a PPAR ligand with a relatively low potency. More powerful new compounds with pan-PPAR activity and proven long-term safety should be highly effective in a clinical setting of patients with coexisting relevant lipid and glucose metabolism disorders.

[A case report of acute neuromyopathy induced by concomitant use of colchicine and bezafibrate]

We report a patient of acute neuromyopathy induced by concomitant use of colchicine and bezafibrate. A 75-year-old man with chronic renal failure and hyperlipidemia treated with bezafibrate (400 mg/day) for 1.5 years had developed watery diarrhea followed by acute tetraparesis, 14 days after the administration of colchicine for recurrent gout. Neurological examination showed proximal muscle weakness with myalgia, distal mild numbness (dysesthesia) of four limbs and generalized decreased or absent reflexies. The findings including elevated serum muscle enzymes, myogenic patterns with widespread myotonic discharge on the electromyography and delayed latency of F-wave on nerve conduction study indicated that the patient's clinical features were consistent with neuromyopathy. Soon after both colchicine and bezafibrate were stopped, the patient's symptoms resolved rapidly, therefore we made a diagnosis of drug-induced neuromyopathy, although rhabdomyolysis with Guillain-Barré syndrome was initially suspected. Recently, there had been reported acute and severe neuromuscular disorder induced by combination therapy with colchicine and anti-hyperlipidemic drugs, and there were clinical similarities between the cases of these reports and our case. Co-administration of colchicine with bezafibrate might accelerate the onset of neuromyopathy in connection with chronic renal failure in this case. Extreme caution is warranted when the patient with renal insufficiency concomitant use of colchicine and bezafibrate.

Bezafibrates Cause Moderate, Reversible Impairment in Renal Function in Patients without Prior Renal Disease

BACKGROUND/AIMS

To determine whether bezafibrates have adverse effects on renal function.

METHODS

(1) A 3-year retrospective survey of 526 patients who were on bezafibrate for a while and 614 controls following fluctuations of serum creatinine levels. (2) A prospective study on 33 patients with previous evidence of bezafibrate-induced elevation in serum creatinine. The patients were examined after 3 months on bezafibrate 400 mg/day and then after 3 months without bezafibrate. Eight patients repeated the tests after 3 months on bezafibrate 200 mg/day.

RESULTS

Retrospective: 295 bezafibrate-treated patients (56%) and 67 controls (11%) demonstrated fluctuations > or = 0.2 mg/dl in serum creatinine levels (p < 0.001); 113 patients (21%) and 16 controls (3%) showed fluctuations > or = 0.3 mg/dl (p < 0.001). Prospective: bezafibrate 400 mg/dl increased serum creatinine from 1.16 +/- 0.19 to 1.42 +/- 0.2 mg/dl (p < 0.001) and urea from 37 +/- 8 to 44 +/- 8 mg/dl (p < 0.001); creatinine clearance (Ccr) decreased from 104 +/- 23 to 82 +/- 27 ml/min (p < 0.001). CPK increased from 82 +/- 32 to 130 +/-58 mg/dl (p < 0.0001) and urinary myoglobin increased from 95.4 +/- 21 to 199 +/- 99 mg/dl (p < 0.0001). The 8 patients given bezafibrate 200 mg/dl experienced similar dose-dependent changes.

CONCLUSIONS

Bezafibrate causes quiet common, dose-dependent and reversible changes in serum creatinine in patients with normal renal function, associated with a significant increase in serum CPK and urine myoglobin, suggestive of drug-induced mild subclinical skeletal muscle injury compromising renal function.

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.

Treatment of fibrate-induced rhabdomyolysis with plasma exchange in ESRD

Hypertriglyceridemia is a common metabolic disorder in patients with chronic renal failure. Fibrate derivatives are often used for lipid lowering in this population with adjusted dosage. However, fibrate-related adverse reaction still occasionally occurs. The authors report a case of end-stage renal disease in a patient who underwent hemodialysis regularly, taking a reduced dosage of bezafibrate (200 mg/d) for refractory hypertriglyceridemia. She did not take any statins, cyclosporine, monoamine oxidase inhibitors, or warfarin concurrently. Rhabdomyolysis was complicated along with an increased serum bezafibrate level. Plasma exchange was performed, which dramatically decreased the level of bezafibrate, and rhabdomyolysis resolved rapidly thereafter. A lower dose of bezafibrate, 200 mg every third day, was prescribed with cautious monitoring of symptoms and laboratory parameters, and better triglyceride control was achieved uneventfully. This is the first report using plasma exchange to remove excessive bezafibrate, a highly protein-bound molecule that is unlikely to be cleared by hemodialysis in an end-stage renal disease patient with serious adverse reaction caused by accumulation of bezafibrate. In contrast to a traditional wait-and-see strategy, plasma exchange seems to be a safe and effective treatment in addition to supportive care for rhabdomyolysis in such clinical scenarios.

Bezafibrate induces a mitochondrial derangement in human cell lines: a PPAR-independent mechanism for a peroxisome proliferator

Bezafibrate is a hypolipidemic drug that belongs to the group of peroxisome proliferators because it binds to peroxisome proliferator-activated receptors type alpha (PPARs). Peroxisome proliferators produce a myriad of extraperoxisomal effects, which are not necessarily dependent on their interaction with PPARs. An investigation on the peculiar activities of bezafibrate could clarify some of the molecular events and the relationship with the biochemical and pharmacological properties of this class of compounds. In this view, the human acute promyelocytic leukemia HL-60 cell line and human rabdomiosarcoma TE-671 cell line were cultured in media containing bezafibrate and a number of observations such as spectrophotometric analysis of mitochondrial respiratory chain enzymes, NMR metabolite determinations, phosphofructokinase enzymatic analysis, and differentiation assays were carried on. Bezafibrate induced a derangement of NADH cytochrome c reductase activity accompanied by metabolic alterations, mainly a shift to anaerobic glycolysis and an increase of fatty acid oxidation, as shown by NMR analysis of culture supernatants where acetate, lactate, and alanine levels increased. On the whole, the present results suggest a biochemical profile and a therapeutic role of this class of PPARs ligands more complex than those previously proposed.

Evaluation of the synergistic adverse effects of concomitant therapy with statins and fibrates on rhabdomyolysis

Rhabdomyolysis is a severe adverse effect of hypolipidaemic agents such as statins and fibrates. We evaluated this muscular cytotoxicity with an in-vitro culture system. Cellular apoptosis was determined using phase-contrast and fluorescein microscopic observation with Hoechst 33342 staining. L6 rat myoblasts were treated with various statins and bezafibrate under various conditions. With statins only, skeletal cytotoxicity was ranked as cerivastatin > fluvastatin > simvastatin > atorvastatin > pravastatin in order of decreasing potency. Combined application of fibrates enhanced atorvastatin-induced myopathy, which causes little apoptosis alone. These results suggest that statins and fibrates synergistically aggravate rhabdomyolysis.

Cell-specific toxicity of fibrates in human embryonal rhabdomyosarcoma cells

The effects of a variety of fibrates on the cell viability were examined in human embryonal rhabdomyosarcoma cells (HRMSC). Five fibrates, including fenofibrate, clofibrate, gemfibrozil, bezafibrate and ciprofibrate, all concentration-dependently reduced the cell viability determined by the mitochondrial enzyme activity. The cell injury occurred time-dependently and was marked at 24-48 h. The toxic action of fibrates was specific to HRMSC, since bezafibrate did not induce any marked changes in the viability of human microvascular endothelial cells or arterial smooth muscle cells. Synergistic cell injury was observed after a combined treatment with bezafibrate and simvastatin, although simvastatin alone reduced the cell viability. The cell injury was characterized by a typical nuclear damage, as evidenced by Hoechst 33342 staining and deoxynucleotidyl transferase dUTP nick-end label-positive staining. Similar cell-specific injury was induced by 8(S)-hydroxyeicosatetraenoic acid, a potent peroxisome proliferator-activated receptor alpha (PPARalpha) agonist. Consistent with these data, a marked expression for PPARalpha mRNA was observed in HRMSC but not in the endothelial or smooth muscle cells. Therefore, it is suggested that fibrates cause a cell-specific injury in HRMSC via activation of PPARalpha. Moreover, our present cell injury model using HRMSC may be useful for elucidating the mechanisms of clinical rhabdomyolysis induced by lipid-lowering agents.

Bezafibrate-induced anaphylactic shock: unusual clinical presentation

We report a case of a patient who suffered generalized urticaria, chest tightness, wheezing, nausea, vomiting, hypotension, and loss of consciousness. Two hours earlier she had taken Eulitop Retard following lunch. She had tolerated all the implicated food after the reaction. Allergy evaluation revealed intense positive responses to intradermal tests with bezafibrate active component and Eulitop Retard (skin tests in control subjects were negative). Specific IgE tests (RAST) to Eulitop Retard were negative. An IgE mechanism is suggested to be responsible for this adverse reaction on the basis of the positive skin tets. The delayed onset (two hours) of this anaphylactic shock is unusual. Although infrequent, it may be caused by the specific pharmacokinetic characteristics of this drug, which is a slow releasing agent, mainly absorbed in the gut. The drug was taken just after lunch, and this concomitant food ingestion could also have produced a delay in gastric drainage and a retarded drug absorption. An IgE-mediated accelerated type reaction could also explain this delay. Apparently the patient reacted after the first contact to the drug, and the absence of a sensitization period is not usual in this type of immune reponse. Finally, we recommend the performance of prick and intradermal skin tests prior to any systemic challenge when allergic reactions to fibric acid derivatives are suspected.

Rhabdomyolysis and acute renal failure following a switchover of therapy between two fibric acid derivatives

Drug induced myopathy has been reported with the use of fibric acid derivatives, hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitors and nicotinic acid. Over the last three decades, hypolipemiants like fibric acid derivatives and statins have been increasingly recognised as causes of rhabdomyolysis and acute renal failure especially during combination therapy and in the presence of underlying renal impairment. We report two cases of bezafibrate-induced rhabdomyolysis in patients with underlying coronary artery disease and pre-existing renal impairment. Both patients developed rhabdomyolysis leading to acute renal failure soon after their hyperlipidaemia treatment was changed from gemfibrozil to bezafibrate. There were no intercurrent illnesses or co-administration of other lipid lowering drugs in both patients. Even though both drugs belong to the same fibric acid derivatives group, these patients developed the complication only after a switchover of therapy.

Fibrate-induced increase in blood urea and creatinine: is gemfibrozil the only innocuous agent?

BACKGROUND

Some reports indicate that fibrates can induce renal dysfunction. However, the clinical characteristics of these episodes, and the respective nephrotoxicity of the four main fibrates used-namely, fenofibrate, bezafibrate, ciprofibrate, and gemfibrozil-remain ill defined.

METHODS

To better characterize this side-effect, we first reviewed the charts of 27 patients from our institution who developed an impairment of renal function during fibrate therapy. We next analysed the articles (n=24) that contained data on renal function in patients taking fibrates (n=2676).

RESULTS

Among our 27 patients, 25 were on fenofibrate therapy, one was taking bezafibrate, and one ciprofibrate. Nineteen were recipients of solid-organ transplants (kidney recipients, n=15; heart or heart-lung recipients, n=4), and eight were non-transplanted patients with some impairment of renal function. Baseline plasma creatinine ranged from 0.9 to 2.9 mg/dl. It increased by a mean of 40% after the start of fibrate therapy. There was a concomitant increase of blood urea values (mean 36%) in most of the patients. Renal function returned to baseline in 18/24 patients after fibrate discontinuation. However, six patients, all transplant recipients, experienced a permanent increase in plasma creatinine. The incidence of fibrate-induced renal dysfunction among our series of kidney transplant recipients was 60%, as it occurred in 15 of the 25 patients who had ever taken fibrates. An increase of mean creatinine values during therapy was described in all papers on fenofibrate (n=7) and bezafibrate (n=8) (range 8-18% and 8-40% respectively), and in three of four papers dealing with ciprofibrate (range 6-16%). No significant renal impairment was described in any of the eight articles reporting data on gemfibrozil therapy.

CONCLUSION

Therapy with fenofibrate, bezafibrate, and ciprofibrate may induce renal dysfunction. Gemfibrozil appears to be devoid of this side-effect.

A paradoxical severe decrease in serum HDL-cholesterol after treatment with a fibrate

There have been a handful of reports in the literature of a paradoxical decrease in serum high density lipoprotein (HDL)-cholesterol in patients on fibrate drugs. The reason for this decline in cardioprotective HDL-cholesterol is not known and may have potential deleterious effects on the patient. This report describes a decrease in serum HDL-cholesterol in a patient on both simvastatin and bezafibrate. This patient also developed abnormal renal function, probably interstitial nephritis. In addition, the literature of fibrate induced serum HDL-cholesterol decline is reviewed and possible mechanisms for this phenomenon discussed.

[Marked creatine-phosphokinase elevation in myopathy after treatment with bezafibrate]

Bezafibrate is a fibric acid derivative which has been widely used in the past 15 years. Recent studies have elucidated much of its mechanism of action, which mainly results in reduction of VLDL and triglyceride levels and in elevation of HDL. The drug is relatively safe and its side-effects well known, mild, and reversible. The most severe side-effect is myositis, varying from mild flu-like symptoms to rhabdomyolysis, which is extremely rare. The underlying situations most frequently associated with bezafibrate-induced myositis are renal insufficiency and concomitant treatment with certain other drugs. We describe 2 women who developed severe myositis with bezafibrate treatment. 1, aged 43, who had moderate diabetes but no renal insufficiency, was treated with metformin and warfarin, which can interact with bezafibrate and affect its metabolism. The other, aged 54, had renal insufficiency and was on home peritoneal dialysis. Her bezafibrate dose had been increased because of very high triglyceride levels. The aim of the study is to call attention to this significant side-effect of benzafibrate and to ways of preventing it.

Bezafibrate Infarction Prevention (BIP) study. Secondary prevention by raising HDL cholesterol and reducing triglycerides in patients with coronary artery disease

BACKGROUND

Coronary heart disease patients with low high-density lipoprotein cholesterol (HDL-C) levels, high triglyceride levels, or both are at an increased risk of cardiovascular events, but the clinical impact of raising HDL-C or decreasing triglycerides remains to be confirmed.

METHODS AND RESULTS

In a double-blind trial, 3090 patients with a previous myocardial infarction or stable angina, total cholesterol of 180 to 250 mg/dL, HDL-C < or =45 mg/dL, triglycerides < or =300 mg/dL, and low-density lipoprotein cholesterol < or =180 mg/dL were randomized to receive either 400 mg of bezafibrate per day or a placebo; they were followed for a mean of 6.2 years. The primary end point was fatal or nonfatal myocardial infarction or sudden death. Bezafibrate increased HDL-C by 18% and reduced triglycerides by 21%. The frequency of the primary end point was 13. 6% on bezafibrate versus 15.0% on placebo (P=0.26). After 6.2 years, the reduction in the cumulative probability of the primary end point was 7.3%, (P=0.24). In a post hoc analysis in the subgroup with high baseline triglycerides (> or =200 mg/dL), the reduction in the cumulative probability of the primary end point by bezafibrate was 39.5% (P=0.02). Total and noncardiac mortality rates were similar, and adverse events and cancer were equally distributed.

CONCLUSIONS

Bezafibrate was safe and effective in elevating HDL-C levels and lowering triglycerides. An overall trend in a reduction of the incidence of primary end points was observed. The reduction in the primary end point in patients with high baseline triglycerides (> or =200 mg/dL) requires further confirmation.

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.

Relapsing acute pancreatitis induced by re-exposure to the cholesterol lowering agent bezafibrate

We report a 75-yr-old patient, who presented three times with acute pancreatitis, accompanied by high temperature, shock, and multiorgan involvement and associated each time with exposure to the cholesterol lowering agent bezafibrate. Extensive workup excluded other possible causes for recurrent pancreatitis in this patient, further supporting bezafibrate as the cause of the patient's acute illness. Based on the short time elapsing between rechallenge and development of manifestations and the specific features of the attacks, we proposed hypersensitivity to bezafibrate as the underlying mechanism. The present report includes, for the first time, bezafibrate among definite causes of acute pancreatitis.

A comparison of the use, effectiveness and safety of bezafibrate, gemfibrozil and simvastatin in normal clinical practice using the New Zealand Intensive Medicines Monitoring Programme (IMMP)

AIMS

Because of the importance of treating dyslipidaemia in the prevention of ischaemic heart disease and because patient selection criteria and outcomes in clinical trials do not necessarily reflect what happens in normal clinical practice, we compared outcomes from bezafibrate, gemfibrozil and simvastatin therapy under conditions of normal use.

METHODS

A random sample of 200 patients was selected from the New Zealand Intensive Medicines Monitoring Programme's (IMMP) patient cohorts for each drug. Questionnaires sent to prescribers requested information on indications, risk factors for ischaemic heart disease, lipid profiles with changes during treatment and reasons for stopping therapy.

RESULTS

80% of prescribers replied and 83% of these contained useful information. The three groups were similar for age, sex and geographical region, but significantly more patients on bezafibrate had diabetes and/or hypertension than those on gemfibrozil or simvastatin. After treatment and taking the initial measure into account, the changes in serum lipid values were consistent with those generally observed, but with gemfibrozil being significantly less effective than expected. More patients (15.8%S) stopped gemfibrozil because of an inadequate response compared with bezafibrate (5.4%) and simvastatin (1.6%). Gemfibrozil treatment was also withdrawn significantly more frequently due to a possible adverse reaction compared with the other two drugs.

CONCLUSIONS

In normal clinical practice in New Zealand gemfibrozil appears less effective and more frequently causes adverse effects leading to withdrawal of treatment than either bezafibrate or simvastatin.

Results of the Bezafibrate Coronary Atherosclerosis Intervention Trial (BECAIT) and an update on trials now in progress

Bezafibrate is a latest generation fibrate derivative that substantially reduces total plasma cholesterol and triglyceride concentrations and increases high density lipoprotein (HDL) cholesterol. The Bezafibrate Coronary Atherosclerosis Intervention Trial (BECAIT) was a double-blind, placebo-controlled trial over 5 years to assess the angiographic benefits of bezafibrate retard (400 mg. day (-1) in young, male, post-myocardial infarction (post-MI) patients. The trial demonstrated that without lowering serum low density lipoprotein cholesterol, progression of coronary atherosclerosis was prevented and the coronary event rate reduced. In subgroup analyse, bezafibrate decreased the rate of progression of coronary atherosclerosis and coronary event rate in young post-MI patients, primarily by slowing the progression of mild-to-moderate lesions. Additional studies are underway to explore further the benefits of this fibrate in coronary heart disease. The Bezafibrate Infarction Prevention study is the first trial to investigate the effects of raising HDL cholesterol and lowering triglycerides in patients with established coronary disease. The Lower Extremity Arterial Disease Event Reduction study is assessing the benefit of lowering fibrinogen in the prevention of major ischaemic heart disease and stroke in patients with peripheral vascular disease.

Baseline characteristics of patients participating in the Bezafibrate Infarction Prevention (BIP) Study

Low high density lipoprotein (HDL) cholesterol, elevated triglycerides, or a combination of both, carries an increased risk of coronary heart disease (CHD). The benefit of therapy that increases serum HDL cholesterol concentrations and lowers triglyceride concentrations on the reduced incidence of myocardial infarctions and mortality has not been unequivocally demonstrated in healthy persons or patients with CHD. The Bezafibrate Infarction Prevention (BIP) study randomized men and women, with CHD and with total serum cholesterol 180 - 250 mg. dl-1, low density lipoprotein (LDL) cholesterol < or = 180 mg. dl-1 (< or = 160 mg. dl-1 below age 50 years), HDL cholesterol < or = 45mg. dl-1 and triglycerides < or = 300 mg. dl-1, to bezafibrate retard (400 mg once daily) or placebo. In addition to its effect on the lipids, this drug significantly lower plasma fibrinogen. The demographic, clinical and biochemical characteristics and existing cardiovascular therapy at baseline of 3122 patients randomized onto the study are presented here. A comparison is made with other on-going or recently published secondary prevention studies of lipid modification in CHD patients.

Efficacy and tolerance of 400 MG bezafibrate in diabetic and hyperlipidaemic patients

The authors report the results of an open clinical study using 400 mg Bezafibrate once a day. Among 25 diabetic patients (type II.) underwent a 4 weeks period with nutritional advice. Average changes from inclusion levels were -24% for total cholesterol, -56% for triglicerides, +11.9% for HDL-cholesterol, -19% for plama fibrinogen. In conclusion, bezafibrate at a daily dose of 400 mg had significant lipid-modifying properties but also exhibited a beneficial effect on other related risk factors such as fibrinogen reduction.

Warfarin potentiation with bezafibrate

Two cases are described in which lack of awareness of the potentiation of bezafibrate on warfarin was of clinical importance.

Comparison of bezafibrate and simvastatin in the treatment of dyslipidaemia in patients with NIDDM

Fibrates and HMG CoA reductase inhibitors are commonly used in the treatment of diabetic dyslipidaemia. However, these two groups of drugs have not been compared in diabetic patients in a randomized controlled trial. Therefore, a multicentre study was performed in 73 subjects with non-insulin-dependent (Type 2) diabetes mellitus (NIDDM) and combined hyperlipidaemia (serum cholesterol 6.2-10.0 mmol l(-1), serum triglycerides 2.3-10.0 mmol l(-1)), comparing the efficacy of 400 mg bezafibrate with 10 mg simvastatin in a double-blind fashion. Treatment with bezafibrate during 12 weeks reduced serum triglycerides significantly more than simvastatin (-41% vs -22%, p < 0.001) and increased HDL cholesterol more (bezafibrate: + 17% vs simvastatin: + 9%, p < 0.05). LDL cholesterol levels decreased by 14% (p < 0.001) during simvastatin and increased by 21% (p < 0.01) during bezafibrate. This increase in LDL cholesterol was positively correlated with fasting serum triglycerides (p < 0.001) and was associated with a reduction of the serum apolipoprotein B concentration, suggesting an increase in LDL particle size. Metabolic control of diabetes (fasting glycaemia; HbA1c) and insulin secretion (C-peptide levels) were unaffected by both treatments. The incidence of side-effects during treatment was similar for both drugs. Thus, 400 mg bezafibrate mainly increases HDL cholesterol and lowers serum triglycerides but at the expense of an increase in LDL cholesterol; 10 mg simvastatin lowers LDL cholesterin more effectively but has a smaller effect on HDL cholesterol and triglycerides.

Morphometry of abnormal peroxisomes induced by withdrawal of bezafibrate, a hypolipidemic drug in male rat hepatocytes

Peroxisomes containing fibrillar structures were induced after 1 week withdrawal of bezafibrate, a peroxisome proliferator. In this report, the relation between the duration of bezafibrate treatment and the induction of abnormal peroxisomes in rat hepatocytes was studied morphometrically. The abnormal peroxisomes did not appear during 3 to 90 days of treatment with bezafibrate, but they appeared after 1 week withdrawal of it. The number and frequency of abnormal peroxisomes were prominent in 3, 7, and 14 days of treatment followed by 1 week of withdrawal of bezafibrate. It was evident that the frequency of abnormal peroxisomes decreased with 30-90 days administration of bezafibrate. This means that long-term (30-90 days) treatment with bezafibrate suppresses the induction of abnormal peroxisomes.

Low total cholesterol is associated with high total mortality in patients with coronary heart disease. The Bezafibrate Infarction Prevention (BIP) Study Group

The present non-intervention screening study was undertaken to explore the relationships between pre-existing low total cholesterol and all-cause mortality. Eleven thousand, five hundred and sixty-three patients with coronary heart disease who attended a screening visit but were not included in the Bezafibrate Infarction Prevention study were followed-up for a mean of 3.3 years after determination of baseline total cholesterol. Five hundred and ninety-five (5%) of this largely unselected population who had total cholesterol levels < or = 160 mg.dl-1 formed the study population. The remaining 10968 patients acted as controls. The relative risk of all-cause mortality among patients with low cholesterol compared to others was 1.49 (95% CI: 1.16-1.91). The relative risk of non-cardiac death was 2.27 times higher in the low cholesterol group than in the controls (95% CI: 1.49-3.45), whereas the risk of cardiac death was the same in both groups (relative risk 1.09; 95% CI: 0.76-1.56). The most frequent cause of non-cardiac death associated with low total cholesterol was cancer. These results in patients with coronary heart disease add weight to previous studies associating low total cholesterol with an increased risk of non-cardiac death. However, a longer follow-up of this cohort of patients is necessary in order to clarify this association.

Enhanced myopathy following administration of hypolipidemic agents under urethane anesthesia

The enhanced effect of urethane anesthesia on the serum creatine kinase (CPK) level following administration of hypolipidemic agents was examined to develop a convenient experimental screening method for drug-induced myopathy. After oral administration of a hypolipidemic agent to rats, 25% urethane solution was infused intravenously at a very low rate using a microinfusion pump. Blood samples were collected 7 h after drug administration and the risk of myopathy was evaluated based on the CPK level. When bezafibrate (BF), simvastatin (SV), or pravastatin (PV) (50-500 mg/kg) was orally administered under urethane infusion, enhanced elevation of the serum CPK level was observed dose dependently for BF and SV, but not for PV. The elevation of serum CPK was much higher with BF than with SV or PV. In addition, when SV or PV (50-500 mg/kg) was coadministered with 50 mg/kg of BF, there was a striking increase in the serum CPK level as compared with the drug alone. Without urethane infusion, no significant elevation in serum CPK level was observed even at a high dose of these hypolipidemic agents. These phenomena suggest that the urethane anesthesia enhanced the elevation of the serum CPK level following administration of hypolipidemic agents. We propose that this method is a simple and speedy screening test for drug-induced myopathy.