GeneralBefore instituting therapy with Lescol®
(fluvastatin sodium) or Lescol® XL (fluvastatin sodium),
an attempt should be made to control hypercholesterolemia with appropriate diet,
exercise, and weight reduction in obese patients, and to treat other underlying
medical problems (see INDICATIONS AND USAGE).
The HMG-CoA reductase inhibitors may cause elevation of creatine
phosphokinase and transaminase levels (see WARNINGS and ADVERSE REACTIONS). This
should be considered in the differential diagnosis of chest pain in a patient on
therapy with fluvastatin sodium.
Homozygous Familial
HypercholesterolemiaHMG-CoA reductase inhibitors are reported to be less effective in
patients with rare homozygous familial hypercholesterolemia, possibly because
these patients have few functional LDL receptors.
Information for PatientsPatients should be advised to report promptly
unexplained muscle pain, tenderness or weakness, particularly if accompanied by
malaise or fever.
Women should be informed that if they become pregnant while receiving
Lescol or Lescol XL the drug should be discontinued immediately to avoid
possible harmful effects on a developing fetus from a relative deficit of
cholesterol and biological products derived from cholesterol. In addition,
Lescol or Lescol XL should not be taken during nursing. (See CONTRAINDICATIONS.)
Drug InteractionsThe below listed drug interaction information is derived from
studies using immediate- release fluvastatin. Similar studies have not been
conducted using the Lescol XL tablet.
Immunosuppressive Drugs,
Gemfibrozil, Niacin (Nicotinic Acid), Erythromycin
(See WARNINGS: Skeletal Muscle).
In vitro data indicate that fluvastatin metabolism involves multiple
Cytochrome P450 (CYP) isozymes. CYP2C9 isoenzyme is primarily involved in the
metabolism of fluvastatin (~75%), while CYP2C8 and CYP3A4 isoenzymes are
involved to a much less extent, i.e., ~5% and ~20%, respectively. If one pathway
is inhibited in the elimination process of fluvastatin other pathways may
compensate.
In vivo drug interaction studies with CYP3A4 inhibitors/substrates such
as cyclosporine, erythromycin, and itraconazole result in minimal changes in the
pharmacokinetics of fluvastatin, confirming less involvement of CYP3A4 isozyme.
Concomitant administration of fluvastatin and phenytoin increased the levels of
phenytoin and fluvastatin, suggesting predominant involvement of CYP2C9 in
fluvastatin metabolism.
Niacin/Propranolol:
Concomitant administration of immediate- release fluvastatin
sodium with niacin or propranolol has no effect on the bioavailability of
fluvastatin sodium.
Cholestyramine:
Administration of immediate- release fluvastatin sodium
concomitantly with, or up to 4 hours after cholestyramine, results in
fluvastatin decreases of more than 50% for AUC and 50%-80% for Cmax. However, administration of immediate- release fluvastatin
sodium 4 hours after cholestyramine resulted in a clinically significant
additive effect compared with that achieved with either component drug.
Cyclosporine:
Plasma cyclosporine levels remain unchanged when fluvastatin (20
mg daily) was administered concurrently in renal transplant recipients on stable
cyclosporine regimens. Fluvastatin AUC increased 1.9- fold, and Cmax increased 1.3- fold compared to historical controls.
Digoxin:
In a crossover study involving 18 patients chronically receiving
digoxin, a single 40 mg dose of immediate- release fluvastatin had no effect on
digoxin AUC, but had an 11% increase in digoxin Cmax and
small increase in digoxin urinary clearance.
Erythromycin:
Erythromycin (500 mg, single dose) did not affect steady-state
plasma levels of fluvastatin (40 mg daily).
Fluconazole:
Administration of fluvastatin 40 mg single dose to healthy
volunteers pre-treated with fluconazole for 4 days results in an increase of
fluvastatin Cmax (44%) and AUC (84%). Based on this data,
caution should be exercised when fluvastatin is co-administered with
fluconazole.
Itraconazole:
Concomitant administration of fluvastatin (40 mg) and
itraconazole (100 mg daily x 4 days) does not affect plasma itraconazole or
fluvastatin levels.
Gemfibrozil:
There is no change in either fluvastatin (20 mg twice daily) or
gemfibrozil (600 mg twice daily) plasma levels when these drugs are
co-administered.
Phenytoin:
Single morning dose administration of phenytoin (300 mg extended
release) increased mean steady-state fluvastatin (40 mg) Cmax by 27% and AUC by 40% whereas fluvastatin increased the
mean phenytoin Cmax by 5% and AUC by 20%. Patients on
phenytoin should continue to be monitored appropriately when fluvastatin therapy
is initiated or when the fluvastatin dosage is changed.
Diclofenac:
Concurrent administration of fluvastatin (40 mg) increased the
mean Cmax and AUC of diclofenac by 60% and 25%
respectively.
Tolbutamide:
In healthy volunteers, concurrent administration of either single
or multiple daily doses of fluvastatin sodium (40 mg) with tolbutamide (1 g) did
not affect the plasma levels of either drug to a clinically significant
extent.
Glibenclamide
(Glyburide):
In glibenclamide-treated NIDDM patients (n=32), administration of
fluvastatin (40 mg twice daily for 14 days) increased the mean Cmax, AUC, and t1/2 of glibenclamide
approximately 50%, 69% and 121%, respectively. Glibenclamide (5-20 mg daily)
increased the mean Cmax and AUC of fluvastatin by 44% and
51%, respectively. In this study there were no changes in glucose, insulin and
C-peptide levels. However, patients on concomitant therapy with glibenclamide
(glyburide) and fluvastatin should continue to be monitored appropriately when
their fluvastatin dose is increased to 40 mg twice daily.
Losartan:
Concomitant administration of fluvastatin with losartan has no
effect on the bioavailability of either losartan or its active metabolite.
Cimetidine/Ranitidine/Omeprazole:
Concomitant administration of immediate- release fluvastatin
sodium with cimetidine, ranitidine and omeprazole results in a significant
increase in the fluvastatin Cmax (43%, 70% and 50%,
respectively) and AUC (24%-33%), with an 18%-23% decrease in plasma clearance.
Rifampicin:
Administration of immediate- release fluvastatin sodium to
subjects pretreated with rifampicin results in significant reduction in Cmax (59%) and AUC (51%), with a large increase (95%) in plasma
clearance.
Warfarin:
In vitro protein binding studies demonstrated no interaction at
therapeutic concentrations. Concomitant administration of a single dose of
warfarin (30 mg) in young healthy males receiving immediate- release fluvastatin
sodium (40 mg/day x 8 days) resulted in no elevation of racemic warfarin
concentration. There was also no effect on prothrombin complex activity when
compared to concomitant administration of placebo and warfarin. However,
bleeding and/or increased prothrombin times have been reported in patients
taking coumarin anticoagulants concomitantly with other HMG-CoA reductase
inhibitors. Therefore, patients receiving warfarin-type anticoagulants should
have their prothrombin times closely monitored when fluvastatin sodium is
initiated or the dosage of fluvastatin sodium is changed.
Endocrine FunctionHMG-CoA reductase inhibitors interfere with cholesterol synthesis
and lower circulating cholesterol levels and, as such, might theoretically blunt
adrenal or gonadal steroid hormone production.
Fluvastatin exhibited no effect upon non-stimulated cortisol levels and
demonstrated no effect upon thyroid metabolism as assessed by TSH. Small
declines in total testosterone have been noted in treated groups, but no
commensurate elevation in LH occurred, suggesting that the observation was not
due to a direct effect upon testosterone production. No effect upon FSH in males
was noted. Due to the limited number of premenopausal females studied to date,
no conclusions regarding the effect of fluvastatin upon female sex hormones may
be made.
Two clinical studies in patients receiving fluvastatin at doses up to
80 mg daily for periods of 24 to 28 weeks demonstrated no effect of treatment
upon the adrenal response to ACTH stimulation. A clinical study evaluated the
effect of fluvastatin at doses up to 80 mg daily for 28 weeks upon the gonadal
response to HCG stimulation. Although the mean total testosterone response was
significantly reduced (p<0.05) relative to baseline in the 80 mg group, it
was not significant in comparison to the changes noted in groups receiving
either 40 mg of fluvastatin or placebo.
Patients treated with fluvastatin sodium who develop clinical evidence
of endocrine dysfunction should be evaluated appropriately. Caution should be
exercised if an HMG-CoA reductase inhibitor or other agent used to lower
cholesterol levels is administered to patients receiving other drugs (e.g.,
ketoconazole, spironolactone, or cimetidine) that may decrease the levels of
endogenous steroid hormones.
CNS ToxicityCNS effects, as evidenced by decreased activity, ataxia, loss of
righting reflex, and ptosis were seen in the following animal studies: the
18-month mouse carcinogenicity study at 50 mg/kg/day, the 6-month dog study at
36 mg/kg/day, the 6-month hamster study at 40 mg/kg/day, and in acute, high-dose
studies in rats and hamsters (50 mg/kg), rabbits (300 mg/kg) and mice (1500
mg/kg). CNS toxicity in the acute high-dose studies was characterized (in mice)
by conspicuous vacuolation in the ventral white columns of the spinal cord at a
dose of 5000 mg/kg and (in rat) by edema with separation of myelinated fibers of
the ventral spinal tracts and sciatic nerve at a dose of 1500 mg/kg. CNS
toxicity, characterized by periaxonal vacuolation, was observed in the medulla
of dogs that died after treatment for 5 weeks with 48 mg/kg/day; this finding
was not observed in the remaining dogs when the dose level was lowered to 36
mg/kg/day. CNS vascular lesions, characterized by perivascular hemorrhages,
edema, and mononuclear cell infiltration of perivascular spaces, have been
observed in dogs treated with other members of this class. No CNS lesions have
been observed after chronic treatment for up to 2 years with fluvastatin in the
mouse (at doses up to 350 mg/kg/day), rat (up to 24 mg/kg/day), or dog (up to 16
mg/kg/day).
Prominent bilateral posterior Y suture lines in the ocular lens were
seen in dogs after treatment with 1, 8, and 16 mg/kg/day for 2 years.
Carcinogenesis, Mutagenesis,
Impairment of FertilityA 2-year study was performed in rats at dose levels of 6, 9, and
18-24 (escalated after 1 year) mg/kg/day. These treatment levels represented
plasma drug levels of approximately 9, 13, and 26-35 times the mean human plasma
drug concentration after a 40 mg oral dose. A low incidence of forestomach
squamous papillomas and 1 carcinoma of the forestomach at the 24 mg/kg/day dose
level was considered to reflect the prolonged hyperplasia induced by direct
contact exposure to fluvastatin sodium rather than to a systemic effect of the
drug. In addition, an increased incidence of thyroid follicular cell adenomas
and carcinomas was recorded for males treated with 18-24 mg/kg/day. The
increased incidence of thyroid follicular cell neoplasm in male rats with
fluvastatin sodium appears to be consistent with findings from other HMG-CoA
reductase inhibitors. In contrast to other HMG-CoA reductase inhibitors, no
hepatic adenomas or carcinomas were observed.
The carcinogenicity study conducted in mice at dose levels of 0.3, 15
and 30 mg/kg/day revealed, as in rats, a statistically significant increase in
forestomach squamous cell papillomas in males and females at 30 mg/kg/day and in
females at 15 mg/kg/day. These treatment levels represented plasma drug levels
of approximately 0.05, 2, and 7 times the mean human plasma drug concentration
after a 40 mg oral dose.
No evidence of mutagenicity was observed in vitro, with or without
rat-liver metabolic activation, in the following studies: microbial mutagen
tests using mutant strains of Salmonella typhimurium
or Escherichia coli; malignant transformation assay
in BALB/3T3 cells; unscheduled DNA synthesis in rat primary hepatocytes;
chromosomal aberrations in V79 Chinese Hamster cells; HGPRT V79 Chinese Hamster
cells. In addition, there was no evidence of mutagenicity in vivo in either a
rat or mouse micronucleus test.
In a study in rats at dose levels for females of 0.6, 2 and 6 mg/kg/day
and at dose levels for males of 2, 10 and 20 mg/kg/day, fluvastatin sodium had
no adverse effects on the fertility or reproductive performance.
Seminal vesicles and testes were small in hamsters treated for 3 months
at 20 mg/kg/day (approximately three times the 40 milligram human daily dose
based on surface area, mg/m2). There was tubular
degeneration and aspermatogenesis in testes as well as vesiculitis of seminal
vesicles. Vesiculitis of seminal vesicles and edema of the testes were also seen
in rats treated for 2 years at 18 mg/kg/day (approximately 4 times the human
Cmax achieved with a 40 milligram daily dose).
PregnancyPregnancy Category X
See CONTRAINDICATIONS.
Fluvastatin sodium produced delays in skeletal development in rats at doses
of 12 mg/kg/day and in rabbits at doses of 10 mg/kg/day. Malaligned thoracic
vertebrae were seen in rats at 36 mg/kg, a dose that produced maternal toxicity.
These doses resulted in 2 times (rat at 12 mg/kg) or 5 times (rabbit at 10
mg/kg) the 40 mg human exposure based on mg/m2 surface
area. A study in which female rats were dosed during the third trimester at 12
and 24 mg/kg/day resulted in maternal mortality at or near term and postpartum.
In addition, fetal and neonatal lethality were apparent. No effects on the dam
or fetus occurred at 2 mg/kg/day. A second study at levels of 2, 6, 12 and 24
mg/kg/day confirmed the findings in the first study with neonatal mortality
beginning at 6 mg/kg. A modified Segment III study was performed at dose levels
of 12 or 24 mg/kg/day with or without the presence of concurrent supplementation
with mevalonic acid, a product of HMG-CoA reductase which is essential for
cholesterol biosynthesis. The concurrent administration of mevalonic acid
completely prevented the maternal and neonatal mortality but did not prevent low
body weights in pups at 24 mg/kg on Days 0 and 7 postpartum. Therefore, the
maternal and neonatal lethality observed with fluvastatin sodium reflect its
exaggerated pharmacologic effect during pregnancy. There are no data with
fluvastatin sodium in pregnant women. However, rare reports of congenital
anomalies have been received following intrauterine exposure to other HMG-CoA
reductase inhibitors. There has been one report of severe congenital bony
deformity, tracheo-esophageal fistula, and anal atresia (VATER association) in a
baby born to a woman who took another HMG-CoA reductase inhibitor with
dextroamphetamine sulfate during the first trimester of pregnancy. Lescol or Lescol XL should be administered to women of child-bearing
potential only when such patients are highly unlikely to conceive and have been
informed of the potential hazards. If a woman becomes pregnant while
taking Lescol or Lescol XL, the drug should be discontinued and the patient
advised again as to the potential hazards to the fetus.
Nursing MothersBased on preclinical data, drug is present in breast milk in a
2:1 ratio (milk:plasma). Because of the potential for serious adverse reactions
in nursing infants, nursing women should not take Lescol or Lescol XL (see
CONTRAINDICATIONS).
Pediatric UseThe safety and efficacy of Lescol and Lescol XL in children and
adolescent patients 9-16 years of age with heterozygous familial
hypercholesterolemia have been evaluated in open-label, uncontrolled clinical
trials of 2 years' duration. The most common adverse events observed were
influenza and infections. In these limited uncontrolled studies, there was no
detectable effect on growth or sexual maturation in the adolescent boys or on
menstrual cycle length in girls. See CLINICAL STUDIES: Heterozygous Familial
Hypercholesterolemia in Pediatric Patients; ADVERSE REACTIONS: Pediatric
Patients (9-16 years of age); and DOSAGE AND ADMINISTRATION: Heterozygous
Familial Hypercholesterolemia in Pediatric Patients. Adolescent females should
be counseled on appropriate contraceptive methods while on fluvastatin therapy
(see CONTRAINDICATIONS: Pregnancy and Lactation)
.
Geriatric UseThe effect of age on the pharmacokinetics of immediate- release
fluvastatin sodium was evaluated. Results indicate that for the general patient
population plasma concentrations of fluvastatin sodium do not vary as a function
of age. (See also CLINICAL PHARMACOLOGY:
Pharmacokinetics/Metabolism.) Elderly patients (>65
years of age) demonstrated a greater treatment response in respect to LDL-C,
Total-C and LDL/HDL ratio than patients <65 years of age.