Lipofen

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rate observed in clinical practice.

Adverse reactions reported by 2% or more of patients treated with fenofibrate (and greater than placebo) during the double-blind, placebo-controlled trials, regardless of causality, are listed in Table 1 below. Adverse events led to discontinuation of treatment in 5.0% of patients treated with fenofibrate and in 3.0% treated with placebo. Increases in liver function tests were the most frequent events, causing discontinuation of fenofibrate treatment in 1.6% of patients in double-blind trials.

Table 1: Adverse Reactions Reported by 2% or More of Patients Treated with Fenofibrate and Greater than Placebo During the Double-Blind, Placebo-Controlled Trials

Postmarketing Experience

The following adverse reactions have been identified during postapproval use of fenofibrate: myalgia, rhabdomyolysis, pancreatitis, acute renal failure, muscle spasm, hepatitis, cirrhosis, anemia, arthralgia, decreases in hemoglobin, decreases in hematocrit, white blood cell decreases, asthenia, and severely depressed HDL cholesterol levels. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Read the entire FDA prescribing information for Lipofen (Fenofibrate)

Fenofibrate is a prescription medication used to lower cholesterol and triglycerides (a type of fat), and to increase "good" cholesterol in the blood. It may be used alone or with other cholesterol-lowering medications. Fenofibrate belongs to a group of drugs called fibrates which work by increasing the activity of an enzyme involved in removing triglycerides and cholesterols from the body.

This medication comes in capsule and tablet form and is taken once a day, with or without food.

Common side effects of fenofibrate include headaches, heartburn, nausea, and muscle aches.

Lipofen is part of the drug class:

• Fibrates

Fenofibrate may cause serious side effects, including:

• muscle pain, tenderness, or weakness. 
• tiredness and fever.
• abdominal pain, nausea, or vomiting. These may be signs of inflammation (swelling) of the gallbladder or pancreas.

Call your healthcare provider right away if you have any of these serious side effects.

The most common side effects with fenofibrate include:

• headache
• heartburn (indigestion)
• nausea
• muscle aches
• increases in muscle or liver enzymes that are measured by blood tests

Tell your healthcare provider if you have any side effect that bothers you or that does not go away. These are not all the possible side effects of fenofibrate. For more information, ask your healthcare provider or pharmacist.

Medicines can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of fenofibrate there are no specific foods that you must exclude from your diet when receiving fenofibrate.

Fenofibrate can be used with other cholesterol-lowering medicines called statins. Grapefruit and grapefruit juice may interact with statins and lead to potentially dangerous effects. Discuss the use of grapefruit products with your doctor.

If you take too much fenofibrate call your local Poison Control Center or seek emergency medical treatment right away.

You should not use fenofibrate if you have liver disease, gallbladder disease, severe kidney disease, or if you are on dialysis.

Do not breast-feed while taking fenofibrate.

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

In the U.S.

• Antara
• Fenoglide
• Lipofen
• Lofibra
• Tricor
• Triglide

Available Dosage Forms:

• Tablet
• Capsule

Therapeutic Class: Antihyperlipidemic

Chemical Class: Fibric Acid

Mechanism of Action

The active moiety of Lipofen is fenofibric acid. The pharmacological effects of fenofibric acid in both animals and humans have been extensively studied through oral administration of fenofibrate.

The lipid-modifying effects of fenofibric acid seen in clinical practice have been explained in vivo in transgenic mice and in vitro in human hepatocyte cultures by the activation of peroxisome proliferator activated receptor α (PPARα). Through this mechanism, fenofibrate increases lipolysis and elimination of triglyceride-rich particles from plasma by activating lipoprotein lipase and reducing production of apoprotein C-III (an inhibitor of lipoprotein lipase activity). The resulting decrease in triglycerides produces an alteration in the size and composition of LDL from small, dense particles (which are thought to be atherogenic due to their susceptibility to oxidation), to large buoyant particles. These larger particles have a greater affinity for cholesterol receptors and are catabolized rapidly. Activation of PPARα also induces an increase in the synthesis of apolipoproteins AI, AII and HDL cholesterol.

Fenofibrate also reduces serum uric acid levels in hyperuricemic and normal individuals by increasing the urinary excretion of uric acid.

Pharmacodynamics

Elevated levels of total-c, LDL-C, and apo B and decreased levels of HDL-C and its transport complex, Apo AI and Apo AII, are risk factors for atherosclerosis. Epidemiologic investigations have established that cardiovascular morbidity and mortality vary directly with the level of total-c, LDL-C, and triglycerides, and inversely with the level of HDL-C. The independent effect of raising HDL-C or lowering triglycerides (TG) on the risk of cardiovascular morbidity and mortality has not been determined.

Fenofibric acid, the active metabolite of fenofibrate, produces reductions in total cholesterol, LDL cholesterol, apolipoprotein B, total triglycerides and triglyceride rich lipoprotein (VLDL) in treated patients. In addition, treatment with fenofibrate results in increases in high density lipoprotein (HDL) and apolipoproteins AI and AII.

Pharmacokinetics

The extent and rate of absorption of fenofibric acid after administration of 150 mg Lipofen capsules are equivalent under low-fat and high-fat fed conditions to 160 mg TriCor® tablets.

Fenofibrate is a pro-drug of the active chemical moiety fenofibric acid. Fenofibrate is converted by ester hydrolysis in the body to fenofibric acid which is the active constituent measurable in the circulation. In a bioavailability study with Lipofen capsules 200 mg, following single-dose administration, the plasma concentration (AUC) for the parent compound fenofibrate was approximately 40 μg/mL compared to 204 μg/mL for the metabolite, fenofibric acid. In the same study, the half-life was observed to be 0.91 hrs for the parent compound versus 16.76 hrs for the metabolite.

Absorption: The absolute bioavailability of fenofibrate cannot be determined as the compound is virtually insoluble in aqueous media suitable for injection. However, fenofibrate is well absorbed from the gastrointestinal tract. Following oral administration in healthy volunteers, approximately 60% of a single dose of radiolabeled fenofibrate appeared in urine, primarily as fenofibric acid and its glucuronate conjugate, and 25% was excreted in the feces. Peak plasma levels of fenofibric acid occur within approximately 5 hours after oral administration.

The absorption of fenofibrate is increased when administered with food. With Lipofen, the extent of absorption is increased by approximately 58% and 25% under high-fat fed and low-fat fed conditions as compared to fasting conditions, respectively.

In a single dose and multiple dose bioavailability study with Lipofen capsules 200 mg, the extent of absorption (AUC) of fenofibric acid, the principal metabolite of fenofibrate, was 42% larger at steady state compared to single-dose administration. The rate of absorption (Cmax) of fenofibric acid was 73% greater after multiple-dose than after single-dose administration.

The extent of absorption of Lipofen in terms of AUC value of fenofibric acid increased in a less than proportional manner while the rate of absorption in terms of Cmax value of fenofibric acid increased proportionally related to dose.

Distribution: Upon multiple dosing of fenofibrate, fenofibric acid steady state is achieved after 5 days. Plasma concentrations of fenofibric acid at steady state are slightly more than double those following a single dose. Serum protein binding was approximately 99% in normal and hyperlipidemic subjects.

Metabolism: Following oral administration, fenofibrate is rapidly hydrolyzed by esterases to the active metabolite, fenofibric acid; unchanged fenofibrate is detected at low concentrations in plasma compared to fenofibric acid over most of the single dose and multiple dosing periods.

Fenofibric acid is primarily conjugated with glucuronic acid and then excreted in urine. A small amount of fenofibric acid is reduced at the carbonyl moiety to a benzhydrol metabolite which is, in turn, conjugated with glucuronic acid and excreted in urine.

In vitro and in vivo metabolism data indicate that neither fenofibrate nor fenofibric acid undergo oxidative metabolism (e.g., cytochrome P450) to a significant extent.

Elimination: After absorption, fenofibrate is mainly excreted in the urine in the form of metabolites, primarily fenofibric acid and fenofibric acid glucuronide. After administration of radiolabeled fenofibrate, approximately 60% of the dose appeared in the urine and 25% was excreted in feces.

Fenofibric acid is eliminated with a half-life of approximately 20 hours allowing once daily dosing.

Geriatrics: In elderly volunteers 77 to 87 years of age, the apparent oral clearance of fenofibric acid following a single oral dose of fenofibrate was 1.2 L/h, which compares to 1.1 L/h in young adults. This indicates that an equivalent dose of Lipofen can be used in elderly subjects with normal renal function, without increasing accumulation of the drug or metabolites [see Dosage and Administration (2.5) and Use in Specific Populations (8.5)].

Pediatrics: Pharmacokinetics of Lipofen has not been studied in pediatric patients.

Gender: No pharmacokinetic difference between males and females has been observed for fenofibrate.

Race: The influence of race on the pharmacokinetics of fenofibrate has not been studied, however fenofibrate is not metabolized by enzymes known for exhibiting inter-ethnic variability.

Renal Impairment: The pharmacokinetics of fenofibric acid was examined in patients with mild, moderate and severe renal impairment.  Patients with mild (estimated glomerular filtration rate eGFR 60-89 ml/min/1.73m2) to moderate (eGFR 30-59 mL/min/1.73m2) renal impairment had similar exposure but an increase in the half-life for fenofibric acid was observed as compared to that of healthy subjects. Patients with severe renal impairment (eGFR <30 mL/min/1.73m2) showed a 2.7-fold increase in exposure for fenofibric acid and increased accumulation of fenofibric acid during chronic dosing compared to that of healthy subjects. In patients with mild to moderate renal impairment, treatment with Lipofen should be initiated at a dose of 50 mg per day, and increased only after evaluation of the effects on renal function and lipid levels at this dose. Based on these findings, the use of Lipofen should be avoided in patients who have severe renal impairment.

Hepatic Impairment: No pharmacokinetic studies have been conducted in patients having hepatic impairment.

Drug-Drug Interactions: In vitro studies using human liver microsomes indicate that fenofibrate and fenofibric acid are not inhibitors of cytochrome P450 (CYP) isoforms CYP3A4, CYP2D6, CYP2E1, or CYP1A2. They are weak inhibitors of CYP2C8, CYP2C19 and CYP2A6, and mild to moderate inhibitors of CYP2C9 at therapeutic concentrations.

Table 2 describes the effects of co-administered drugs on fenofibric acid systemic exposure. Table 3 describes the effects of fenofibrate on co-administered drugs.