Pediatric Patients 2 to less than 12 years of age and 12 to 14 years of age with body weight less than 50 kg

If patient response is inadequate and the patient is able to tolerate the initial intravenous maintenance dose, the maintenance dose may be increased by 1 mg/kg steps. If patient response is inadequate and the patient is able to tolerate the oral maintenance dose, the dose may be increased by 1 mg/kg steps or 50 mg steps to a maximum of 350 mg every 12 hours. If patients are unable to tolerate the initial intravenous maintenance dose, reduce the dose by 1 mg/kg steps. If patients are unable to tolerate the oral maintenance dose, reduce the dose by 1 mg/kg or 50 mg steps.

Pediatric patients 12 to 14 years of age weighing greater than or equal to 50 kg and 15 years of age and older regardless of body weight

Use the optimal method for titrating dosage recommended for adults [see Dosage and Administration (2.3)].

Overview

The most frequently reported adverse reactions (see Table 4) in the adult therapeutic trials were visual disturbances (18.7%), fever (5.7%), nausea (5.4%), rash (5.3%), vomiting (4.4%), chills (3.7%), headache (3%), liver function test increased (2.7%), tachycardia (2.4%), hallucinations (2.4%). The adverse reactions which most often led to discontinuation of voriconazole therapy were elevated liver function tests, rash, and visual disturbances [see Warning and Precautions (5.1, 5.4) and Adverse Reactions (6.1)].

The data described in Table 4 reflect exposure to voriconazole in 1,655 patients in nine therapeutic studies. This represents a heterogeneous population, including immunocompromised patients, e.g., patients with hematological malignancy or HIV and non-neutropenic patients. This subgroup does not include healthy subjects and patients treated in the compassionate use and non-therapeutic studies. This patient population was 62% male, had a mean age of 46 years (range 11 to 90, including 51 patients aged 12 to 18 years), and was 78% White and 10% Black. Five hundred sixty one patients had a duration of voriconazole therapy of greater than 12 weeks, with 136 patients receiving voriconazole for over six months. Table 4 includes all adverse reactions which were reported at an incidence of ≥2% during voriconazole therapy in the all therapeutic studies population, studies 307/602 and 608 combined, or study 305, as well as events of concern which occurred at an incidence of <2%.

In study 307/602, 381 patients (196 on voriconazole, 185 on amphotericin B) were treated to compare voriconazole to amphotericin B followed by other licensed antifungal therapy (OLAT) in the primary treatment of patients with acute IA. The rate of discontinuation from voriconazole study medication due to adverse events was 21.4% (42/196 patients). In study 608, 403 patients with candidemia were treated to compare voriconazole (272 patients) to the regimen of amphotericin B followed by fluconazole (131 patients). The rate of discontinuation from voriconazole study medication due to adverse events was 19.5% out of 272 patients. Study 305 evaluated the effects of oral voriconazole (200 patients) and oral fluconazole (191 patients) in the treatment of EC. The rate of discontinuation from voriconazole study medication in Study 305 due to adverse events was 7% (14/200 patients). Laboratory test abnormalities for these studies are discussed under Clinical Laboratory Values below.

†Study 307/602: IA; Study 608: candidemia; Study 305: EC

*Studies 303, 304, 305, 307, 309, 602, 603, 604, 608

**Amphotericin B followed by other licensed antifungal therapy

Visual Disturbances

Voriconazole treatment-related visual disturbances are common. In therapeutic trials, approximately 21% of patients experienced abnormal vision, color vision change and/or photophobia. Visual disturbances may be associated with higher plasma concentrations and/or doses.

The mechanism of action of the visual disturbance is unknown, although the site of action is most likely to be within the retina. In a study in healthy subjects investigating the effect of 28-day treatment with voriconazole on retinal function, voriconazole caused a decrease in the electroretinogram (ERG) waveform amplitude, a decrease in the visual field, and an alteration in color perception. The ERG measures electrical currents in the retina. These effects were noted early in administration of voriconazole and continued through the course of study drug treatment. Fourteen days after the end of dosing, ERG, visual fields and color perception returned to normal [see Warnings and Precautions (5.4)].

Dermatological Reactions

Dermatological reactions were common in patients treated with voriconazole. The mechanism underlying these dermatologic adverse events remains unknown.

Severe cutaneous adverse reactions (SCARs), including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and drug reaction with eosinophilia and systemic symptoms (DRESS) have been reported during treatment with voriconazole. Erythema multiforme has also been reported during treatment with voriconazole [see Warnings and Precautions (5.5) and Adverse Reactions (6.2)].

Voriconazole has also been associated with additional photosensitivity related skin reactions such as pseudoporphyria, cheilitis, and cutaneous lupus erythematosus [see Warnings and Precautions (5.6)].

Less Common Adverse Reactions

The following adverse reactions occurred in <2% of all voriconazole-treated patients in all therapeutic studies (N=1,655). This listing includes events where a causal relationship to voriconazole cannot be ruled out or those which may help the physician in managing the risks to the patients. The list does not include events included in Table 4 above and does not include every event reported in the voriconazole clinical program.

Body as a Whole: Abdominal pain, abdomen enlarged, allergic reaction, anaphylactoid reaction [see Warnings and Precautions (5.3)], ascites, asthenia, back pain, chest pain, cellulitis, edema, face edema, flank pain, flu syndrome, graft versus host reaction, granuloma, infection, bacterial infection, fungal infection, injection site pain, injection site infection/inflammation, mucous membrane disorder, multi-organ failure, pain, pelvic pain, peritonitis, sepsis, substernal chest pain.

Cardiovascular: Atrial arrhythmia, atrial fibrillation, AV block complete, bigeminy, bradycardia, bundle branch block, cardiomegaly, cardiomyopathy, cerebral hemorrhage, cerebral ischemia, cerebrovascular accident, congestive heart failure, deep thrombophlebitis, endocarditis, extrasystoles, heart arrest, hypertension, hypotension, myocardial infarction, nodal arrhythmia, palpitation, phlebitis, postural hypotension, pulmonary embolus, QT interval prolonged, supraventricular extrasystoles, supraventricular tachycardia, syncope, thrombophlebitis, vasodilatation, ventricular arrhythmia, ventricular fibrillation, ventricular tachycardia (including torsade de pointes) [see Warnings and Precautions (5.2)].

Digestive: Anorexia, cheilitis, cholecystitis, cholelithiasis, constipation, diarrhea, duodenal ulcer perforation, duodenitis, dyspepsia, dysphagia, dry mouth, esophageal ulcer, esophagitis, flatulence, gastroenteritis, gastrointestinal hemorrhage, GGT/LDH elevated, gingivitis, glossitis, gum hemorrhage, gum hyperplasia, hematemesis, hepatic coma, hepatic failure, hepatitis, intestinal perforation, intestinal ulcer, jaundice, enlarged liver, melena, mouth ulceration, pancreatitis, parotid gland enlargement, periodontitis, proctitis, pseudomembranous colitis, rectal disorder, rectal hemorrhage, stomach ulcer, stomatitis, tongue edema.

Endocrine: Adrenal cortex insufficiency, diabetes insipidus, hyperthyroidism, hypothyroidism.

Hemic and Lymphatic: Agranulocytosis, anemia (macrocytic, megaloblastic, microcytic, normocytic), aplastic anemia, hemolytic anemia, bleeding time increased, cyanosis, DIC, ecchymosis, eosinophilia, hypervolemia, leukopenia, lymphadenopathy, lymphangitis, marrow depression, pancytopenia, petechia, purpura, enlarged spleen, thrombocytopenia, thrombotic thrombocytopenic purpura.

Metabolic and Nutritional: Albuminuria, BUN increased, creatine phosphokinase increased, edema, glucose tolerance decreased, hypercalcemia, hypercholesteremia, hyperglycemia, hyperkalemia, hypermagnesemia, hypernatremia, hyperuricemia, hypocalcemia, hypoglycemia, hypomagnesemia, hyponatremia, hypophosphatemia, peripheral edema, uremia.

Musculoskeletal: Arthralgia, arthritis, bone necrosis, bone pain, leg cramps, myalgia, myasthenia, myopathy, osteomalacia, osteoporosis.

Nervous System: Abnormal dreams, acute brain syndrome, agitation, akathisia, amnesia, anxiety, ataxia, brain edema, coma, confusion, convulsion, delirium, dementia, depersonalization, depression, diplopia, dizziness, encephalitis, encephalopathy, euphoria, Extrapyramidal Syndrome, grand mal convulsion, Guillain-Barré syndrome, hypertonia, hypesthesia, insomnia, intracranial hypertension, libido decreased, neuralgia, neuropathy, nystagmus, oculogyric crisis, paresthesia, psychosis, somnolence, suicidal ideation, tremor, vertigo.

Respiratory System: Cough increased, dyspnea, epistaxis, hemoptysis, hypoxia, lung edema, pharyngitis, pleural effusion, pneumonia, respiratory disorder, respiratory distress syndrome, respiratory tract infection, rhinitis, sinusitis, voice alteration.

Skin and Appendages: Alopecia, angioedema, contact dermatitis, discoid lupus erythematosis, eczema, erythema multiforme, exfoliative dermatitis, fixed drug eruption, furunculosis, herpes simplex, maculopapular rash, melanoma, melanosis, photosensitivity skin reaction, pruritus, pseudoporphyria, psoriasis, skin discoloration, skin disorder, skin dry, Stevens-Johnson syndrome, squamous cell carcinoma, sweating, toxic epidermal necrolysis, urticaria.

Special Senses: Abnormality of accommodation, blepharitis, color blindness, conjunctivitis, corneal opacity, deafness, ear pain, eye pain, eye hemorrhage, dry eyes, hypoacusis, keratitis, keratoconjunctivitis, mydriasis, night blindness, optic atrophy, optic neuritis, otitis externa, papilledema, retinal hemorrhage, retinitis, scleritis, taste loss, taste perversion, tinnitus, uveitis, visual field defect.

Urogenital: Anuria, blighted ovum, creatinine clearance decreased, dysmenorrhea, dysuria, epididymitis, glycosuria, hemorrhagic cystitis, hematuria, hydronephrosis, impotence, kidney pain, kidney tubular necrosis, metrorrhagia, nephritis, nephrosis, oliguria, scrotal edema, urinary incontinence, urinary retention, urinary tract infection, uterine hemorrhage, vaginal hemorrhage.

Clinical Laboratory Values in Adults

The overall incidence of transaminase increases >3× upper limit of normal (not necessarily comprising an adverse reaction) was 17.7% (268/1,514) in adult subjects treated with voriconazole for therapeutic use in pooled clinical trials. Increased incidence of liver function test abnormalities may be associated with higher plasma concentrations and/or doses. The majority of abnormal liver function tests either resolved during treatment without dose adjustment or resolved following dose adjustment, including discontinuation of therapy.

Voriconazole has been infrequently associated with cases of serious hepatic toxicity including cases of jaundice and rare cases of hepatitis and hepatic failure leading to death. Most of these patients had other serious underlying conditions.

Liver function tests should be evaluated at the start of and during the course of voriconazole therapy. Patients who develop abnormal liver function tests during voriconazole therapy should be monitored for the development of more severe hepatic injury. Patient management should include laboratory evaluation of hepatic function (particularly liver function tests and bilirubin). Discontinuation of voriconazole tablets must be considered if clinical signs and symptoms consistent with liver disease develop that may be attributable to voriconazole tablets [see Warnings and Precautions (5.1)].

Acute renal failure has been observed in severely ill patients undergoing treatment with voriconazole. Patients being treated with voriconazole are likely to be treated concomitantly with nephrotoxic medications and may have concurrent conditions that can result in decreased renal function. It is recommended that patients are monitored for the development of abnormal renal function. This should include laboratory evaluation of serum creatinine.

Tables 5 to 7 show the number of patients with hypokalemia and clinically significant changes in renal and liver function tests in three randomized, comparative multicenter studies. In study 305, patients with EC were randomized to either oral voriconazole or oral fluconazole. In study 307/602, patients with definite or probable IA were randomized to either voriconazole or amphotericin B therapy. In study 608, patients with candidemia were randomized to either voriconazole or the regimen of amphotericin B followed by fluconazole.

*Without regard to baseline value

n = number of patients with a clinically significant abnormality while on study therapy

N = total number of patients with at least one observation of the given lab test while on study therapy

AST = Aspartate aminotransferase;

ALT= alanine aminotransferase

ULN = upper limit of normal

*Without regard to baseline value

**Amphotericin B followed by other licensed antifungal therapy

n = number of patients with a clinically significant abnormality while on study therapy

N = total number of patients with at least one observation of the given lab test while on study therapy

AST = Aspartate aminotransferase; ALT = alanine aminotransferase

 

ULN = upper limit of normal
LLN = lower limit of normal

*Without regard to baseline value

n = number of patients with a clinically significant abnormality while on study therapy

N = total number of patients with at least one observation of the given lab test while on study therapy

AST = Aspartate aminotransferase; ALT = alanine aminotransferase

ULN = upper limit of normal

LLN = lower limit of normal

Serious Adverse Reactions and Adverse Reactions Leading to Discontinuation

In clinical studies, serious adverse reactions occurred in 46% (48/105) of voriconazole treated pediatric patients. Treatment discontinuations due to adverse reactions occurred in 12 /105 (11%) of all patients. Hepatic adverse reactions (i.e. ALT increased; liver function test abnormal; jaundice) 6% (6/105) accounted for the majority of voriconazole treatment discontinuations.

Most Common Adverse Reactions

The most common adverse reactions occurring in ≥5% of pediatric patients receiving voriconazole in the pooled pediatric clinical trials are displayed by body system, in Table 8.

*Reflects all adverse reactions and not treatment-related only.

†Pooled reports include such terms as: amaurosis (partial or total blindness without visible change in the eye); asthenopia (eye strain); chromatopsia (abnormally colored vision); color blindness; diplopia; photopsia; retinal disorder; vision blurred, visual acuity decreased, visual brightness; visual impairment. Several patients had more than one visual disturbance.

‡Pooled reports include such terms as: abdominal pain and abdominal pain, upper.

§Pooled reports include such terms as: ALT abnormal and ALT increased.

¶Pooled reports include such terms as: hallucination; hallucination, auditory; hallucination, visual. Several patients had both visual and auditory hallucinations.

#Pooled reports include such terms as: renal failure and a single patient with renal impairment.

ÞPooled reports include such terms as: rash; rash generalized; rash macular; rash maculopapular; rash pruritic.

Abbreviations: ALT = alanine aminotransferase; LFT = liver function test

The following adverse reactions with incidence less than 5% were reported in 105 pediatric patients treated with voriconazole:

Blood and Lymphatic System Disorders: anemia, leukopenia, pancytopenia

Cardiac Disorders: bradycardia, palpitations, supraventricular tachycardia

Eye Disorders: dry eye, keratitis

Ear and Labyrinth Disorders: tinnitus, vertigo

Gastrointestinal Disorders: abdominal tenderness, dyspepsia

General Disorders and Administration Site Conditions: asthenia, catheter site pain, chills, hypothermia, lethargy

Hepatobiliary Disorders: cholestasis, hyperbilirubinemia, jaundice

Immune System Disorders: hypersensitivity, urticaria

Infections and Infestations: conjunctivitis

Laboratory Investigations: AST increased, blood creatinine increased, gamma-glutamyl transferase increased

Metabolism and Nutrition Disorders: hypercalcemia, hypermagnesemia, hyperphosphatemia, hypoglycemia

Musculoskeletal and Connective Tissue Disorders: arthralgia, myalgia

Nervous System Disorders: ataxia, convulsion, dizziness, nystagmus, paresthesia, syncope

Psychiatric Disorders: affect lability, agitation, anxiety, depression, insomnia

Respiratory Disorders: bronchospasm, nasal congestion, respiratory failure, tachypnea

Skin and Subcutaneous Tissue Disorders: alopecia, dermatitis (allergic, contact, and exfoliative), pruritus

Vascular Disorders: flushing, phlebitis

Hepatic-Related Adverse Reactions in Pediatric Patients

The frequency of hepatic-related adverse reactions in pediatric patients exposed to voriconazole in therapeutic studies was numerically higher than that of adults (28.6% compared to 24.1%, respectively). The higher frequency of hepatic adverse reactions in the pediatric population was mainly due to an increased frequency of liver enzyme elevations (21.9% in pediatric patients compared to 16.1% in adults), including transaminase elevations (ALT and AST combined) 7.6% in the pediatric patients compared to 5.1% in adults.

Clinical Laboratory Values in Pediatric Patients

The overall incidence of transaminase increases >3× upper limit of normal was 27.2% (28/103) in pediatric and 17.7% (268/1514) in adult patients treated with voriconazole in pooled clinical trials. The majority of abnormal liver function tests either resolved on treatment with or without dose adjustment or after voriconazole discontinuation.

A higher frequency of clinically significant liver laboratory abnormalities, irrespective of baseline laboratory values (>3× ULN ALT or AST), was consistently observed in the combined therapeutic pediatric population (15.5% AST and 22.5% ALT) when compared to adults (12.9% AST and 11.6% ALT). The incidence of bilirubin elevation was comparable between adult and pediatric patients. The incidence of hepatic abnormalities in pediatric patients is shown in Table 9.

Animal Data

Voriconazole was administered orally to pregnant rats during organogenesis (gestation days 6 to 17) at 10, 30, and 60 mg/kg/day..Voriconazole was associated with increased incidences in hydroureter and hydronephrosis at 10 mg/kg/day or greater, approximately 0.3 times the recommended human dose (RMD) based on mg/m2, and cleft palate at 60 mg/kg, approximately 2 times the RMD based on mg/m2. Reduced ossification of sacral and caudal vertebrae, skull, pubic, and hyoid bone, supernumerary ribs, anomalies of the sternbrae, and dilatation of the ureter/renal pelvis were also observed at doses of 10 mg/kg or greater. There was no evidence of maternal toxicity at any dose.

Voriconazole was administered orally to pregnant rabbits during the period of organogenesis (gestation days 7 to 19) at 10, 40, and 100 mg/kg/day. Voriconazole was associated with increased post-implantation loss and decreased fetal body weight, in association with maternal toxicity (decreased body weight gain and food consumption) at 100 mg/kg/day (6 times the RMD based on mg/m2). Fetal skeletal variations (increases in the incidence of cervical rib and extra sternebral ossification sites) were observed at 100 mg/kg/day.

In a peri- and postnatal toxicity study in rats, voriconazole was administered orally to female rats from implantation through the end of lactation at 1, 3, and 10 mg/kg/day. Voriconazole prolonged the duration of gestation and labor and produced dystocia with related increases in maternal mortality and decreases in perinatal survival of F1 pups at 10 mg/kg/day, approximately 0.3 times the RMD.

Metabolism

In vitro studies showed that voriconazole is metabolized by the human hepatic cytochrome P450 enzymes, CYP2C19, CYP2C9 and CYP3A4 [see Drug Interactions (7)].

In vivo studies indicated that CYP2C19 is significantly involved in the metabolism of voriconazole. This enzyme exhibits genetic polymorphism [see Clinical Pharmacology (12.5)].

The major metabolite of voriconazole is the N-oxide, which accounts for 72% of the circulating radiolabelled metabolites in plasma. Since this metabolite has minimal antifungal activity, it does not contribute to the overall efficacy of voriconazole.

Excretion

Voriconazole is eliminated via hepatic metabolism with less than 2% of the dose excreted unchanged in the urine. After administration of a single radiolabelled dose of either oral or IV voriconazole, preceded by multiple oral or IV dosing, approximately 80% to 83% of the radioactivity is recovered in the urine. The majority (>94%) of the total radioactivity is excreted in the first 96 hours after both oral and intravenous dosing.

As a result of non-linear pharmacokinetics, the terminal half-life of voriconazole is dose dependent and therefore not useful in predicting the accumulation or elimination of voriconazole.

Male and Female Patients

In a multiple oral dose study, the mean Cmax and AUCτ for healthy young females were 83% and 113% higher, respectively, than in healthy young males (18 to 45 years), after tablet dosing. In the same study, no significant differences in the mean Cmax and AUCτ were observed between healthy elderly males and healthy elderly females (>65 years). In a similar study, after dosing with the oral suspension, the mean AUC for healthy young females was 45% higher than in healthy young males whereas the mean Cmax was comparable between genders. The steady state trough voriconazole concentrations (Cmin) seen in females were 100% and 91% higher than in males receiving the tablet and the oral suspension, respectively.

In the clinical program, no dosage adjustment was made on the basis of gender. The safety profile and plasma concentrations observed in male and female subjects were similar. Therefore, no dosage adjustment based on gender is necessary.

Geriatric Patients

In an oral multiple dose study the mean Cmax and AUCτ in healthy elderly males (≥65 years) were 61% and 86% higher, respectively, than in young males (18 to 45 years). No significant differences in the mean Cmax and AUCτ were observed between healthy elderly females (≥65 years) and healthy young females (18 to 45 years).

In the clinical program, no dosage adjustment was made on the basis of age. An analysis of pharmacokinetic data obtained from 552 patients from 10 voriconazole clinical trials showed that the median voriconazole plasma concentrations in the elderly patients (>65 years) were approximately 80% to 90% higher than those in the younger patients (≤65 years) after either IV or oral administration. However, the safety profile of voriconazole in young and elderly subjects was similar and, therefore, no dosage adjustment is necessary for the elderly [see Use in Special Populations (8.5)].

Pediatric Patients

The recommended doses in pediatric patients were based on a population pharmacokinetic analysis of data obtained from 112 immunocompromised pediatric patients aged 2 to less than 12 years and 26 immunocompromised pediatric patients aged 12 to less than 17 years.

A comparison of the pediatric and adult population pharmacokinetic data indicated that the predicted total exposure (AUC12) in pediatric patients aged 2 to less than 12 years following administration of a 9 mg/kg intravenous loading dose was comparable to that in adults following a 6 mg/kg intravenous loading dose. The predicted total exposures in pediatric patients aged 2 to less than 12 years following intravenous maintenance doses of 4 and 8 mg/kg twice daily were comparable to those in adults following 3 and 4 mg/kg IV twice daily, respectively.

The predicted total exposure in pediatric patients aged 2 to less than 12 years following an oral maintenance dose of 9 mg/kg (maximum of 350 mg) twice daily was comparable to that in adults following 200 mg oral twice daily. An 8 mg/kg intravenous dose will provide voriconazole exposure approximately 2-fold higher than a 9 mg/kg oral dose in pediatric patients aged 2 to less than 12 years.

Voriconazole exposures in the majority of pediatric patients aged 12 to less than 17 years were comparable to those in adults receiving the same dosing regimens. However, lower voriconazole exposure was observed in some pediatric patients aged 12 to less than 17 years with low body weight compared to adults [see Dosage and Administration (2.4)].

Limited voriconazole trough plasma samples were collected in pediatric patients aged 2 to less than 18 years with IA or invasive candidiasis including candidemia, and EC in two prospective, open-label, non-comparative, multicenter clinical studies. In eleven pediatric patients aged 2 to less than 12 years and aged 12 to 14 years, with body weight less than 50 kg, who received 9 mg/kg intravenously every 12 hours as a loading dose on the first day of treatment, followed by 8 mg/kg every 12 hours as an intravenous maintenance dose, or 9 mg/kg every 12 hours as an oral maintenance dose, the mean trough concentration of voriconazole was 3.6 mcg/mL (range 0.3 to 10.7 mcg/mL). In four pediatric patients aged 2 to less than 12 years and aged 12 to 14 years, with body weight less than 50 kg, who received 4 mg/kg intravenously every 12 hours, the mean trough concentration of voriconazole was 0.9 mcg/mL (range 0.3 to 1.6 mcg/mL) [see Clinical Studies (14.5)].

Patients with Hepatic Impairment

After a single oral dose (200 mg) of voriconazole in 8 patients with mild (Child-Pugh Class A) and 4 patients with moderate (Child-Pugh Class B) hepatic impairment, the mean systemic exposure (AUC) was 3.2-fold higher than in age and weight matched controls with normal hepatic function. There was no difference in mean peak plasma concentrations (Cmax) between the groups. When only the patients with mild (Child-Pugh Class A) hepatic impairment were compared to controls, there was still a 2.3-fold increase in the mean AUC in the group with hepatic impairment compared to controls.

In an oral multiple dose study, AUCτ was similar in 6 subjects with moderate hepatic impairment (Child-Pugh Class B) given a lower maintenance dose of 100 mg twice daily compared to 6 subjects with normal hepatic function given the standard 200 mg twice daily maintenance dose. The mean peak plasma concentrations (Cmax) were 20% lower in the hepatically impaired group. No pharmacokinetic data are available for patients with severe hepatic cirrhosis (Child-Pugh Class C) [see Dosage and Administration (2.5)].

Patients with Renal Impairment

In a single oral dose (200 mg) study in 24 subjects with normal renal function and mild to severe renal impairment, systemic exposure (AUC) and peak plasma concentration (Cmax) of voriconazole were not significantly affected by renal impairment. Therefore, no adjustment is necessary for oral dosing in patients with mild to severe renal impairment.

In a multiple dose study of IV voriconazole (6 mg/kg IV loading dose × 2, then 3 mg/kg IV × 5.5 days) in 7 patients with moderate renal dysfunction (creatinine clearance 30 to 50 mL/min), the systemic exposure (AUC) and peak plasma concentrations (Cmax) were not significantly different from those in 6 subjects with normal renal function.

However, in patients with moderate renal dysfunction (creatinine clearance 30 to 50 mL/min), accumulation of the intravenous vehicle, SBECD, occurs. The mean systemic exposure (AUC) and peak plasma concentrations (Cmax) of SBECD were increased 4-fold and almost 50%, respectively, in the moderately impaired group compared to the normal control group.

A pharmacokinetic study in subjects with renal failure undergoing hemodialysis showed that voriconazole is dialyzed with clearance of 121 mL/min. The intravenous vehicle, SBECD, is hemodialyzed with clearance of 55 mL/min. A 4-hour hemodialysis session does not remove a sufficient amount of voriconazole to warrant dose adjustment [see Dosage and Administration (2.6)].

Patients at Risk of Aspergillosis

The observed voriconazole pharmacokinetics in patients at risk of aspergillosis (mainly patients with malignant neoplasms of lymphatic or hematopoietic tissue) were similar to healthy subjects.

Effects of Other Drugs on Voriconazole

Voriconazole is metabolized by the human hepatic cytochrome P450 enzymes CYP2C19, CYP2C9, and CYP3A4. Results of in vitro metabolism studies indicate that the affinity of voriconazole is highest for CYP2C19, followed by CYP2C9, and is appreciably lower for CYP3A4. Inhibitors or inducers of these three enzymes may increase or decrease voriconazole systemic exposure (plasma concentrations), respectively.

Effects of Voriconazole on Other Drugs

In vitro studies with human hepatic microsomes show that voriconazole inhibits the metabolic activity of the cytochrome P450 enzymes CYP2C19, CYP2C9, and CYP3A4. In these studies, the inhibition potency of voriconazole for CYP3A4 metabolic activity was significantly less than that of two other azoles, ketoconazole and itraconazole. In vitro studies also show that the major metabolite of voriconazole, voriconazole N-oxide, inhibits the metabolic activity of CYP2C9 and CYP3A4 to a greater extent than that of CYP2C19. Therefore, there is potential for voriconazole and its major metabolite to increase the systemic exposure (plasma concentrations) of other drugs metabolized by these CYP450 enzymes.

Two-Way Interactions

Other Two-Way Interactions Expected to be Significant Based on In Vitro and In Vivo Findings: