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CLARINEX
2014-01-06 11:32:24 来源: 作者: 【 】 浏览:440次 评论:0
HIGHLIGHTS OF PRESCRIBING INFORMATION
These highlights do not include all the information needed to use CLARINEX® safely and effectively. See full prescribing information for CLARINEX.

CLARINEX® Tablets, RediTabs, and Oral Solution
(desloratadine) for oral use
Initial U.S. Approval: 2001


 

 

INDICATIONS AND USAGE

 

CLARINEX is indicated for:

  • Seasonal Allergic Rhinitis: relief of nasal and non-nasal symptoms in patients 2 years of age and older. (1.1)
  • Perennial Allergic Rhinitis: relief of nasal and non-nasal symptoms in patients 6 months of age and older. (1.2)
  • Chronic Idiopathic Urticaria: symptomatic relief of pruritus, reduction in the number of hives, and size of hives in patients 6 months of age and older. (1.3)
 

DOSAGE AND ADMINISTRATION

 

Dosage (by age):

Adults and adolescents 12 years of age and over:

  • CLARINEX Tablets - one 5 mg tablet once daily or
  • CLARINEX RediTabs Tablets - one 5 mg tablet once daily or
  • CLARINEX Oral Solution - 2 teaspoonfuls (5 mg in 10 mL) once daily (2)

Children 6 to 11 years of age:

  • CLARINEX Oral Solution - 1 teaspoonful (2.5 mg in 5 mL) once daily or
  • CLARINEX RediTabs Tablets - one 2.5 mg tablet once daily (2)

Children 12 months to 5 years of age:

  • CLARINEX Oral Solution - 1/2 teaspoonful (1.25 mg in 2.5 mL) once daily (2)

Children 6 to 11 months of age:

  • CLARINEX Oral Solution - 2 mL (1 mg) once daily (2)
 

DOSAGE FORMS AND STRENGTHS

 
  • CLARINEX Tablets - 5 mg (3)
  • CLARINEX RediTabs (orally-disintegrating tablets) - 5 mg (3)
  • CLARINEX RediTabs (orally-disintegrating tablets) - 2.5 mg (3)
  • CLARINEX Oral Solution - 0.5 mg/1 mL (3)
 

CONTRAINDICATIONS

 
  • Hypersensitivity (4, 6.2)
 

WARNINGS AND PRECAUTIONS

 
  • Hypersensitivity reactions including rash, pruritus, urticaria, edema, dyspnea, and anaphylaxis have been reported. In such cases, stop CLARINEX at once and consider alternative treatments. (5.1)
 

ADVERSE REACTIONS

 
  • The most common adverse reactions (reported in ≥2% of adult and adolescent patients with allergic rhinitis and greater than placebo) were pharyngitis, dry mouth, myalgia, fatigue, somnolence, dysmenorrhea. (6.1)

To report SUSPECTED ADVERSE REACTIONS, contact Schering Corporation, a subsidiary of Merck & Co., Inc., at 1-800-526-4099 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

 

USE IN SPECIFIC POPULATIONS

 
  • Renal impairment: dosage adjustment is recommended (2.5, 8.6, 12.3)
  • Hepatic impairment: dosage adjustment is recommended (2.5, 8.7, 12.3)

See 17 for PATIENT COUNSELING INFORMATION and FDA-approved patient labeling

Revised: 12/2010

FULL PRESCRIBING INFORMATION: CONTENTS*
*
Sections or subsections omitted from the full prescribing information are not listed

1 INDICATIONS AND USAGE

1.1 Seasonal Allergic Rhinitis

1.2 Perennial Allergic Rhinitis

1.3 Chronic Idiopathic Urticaria

2 DOSAGE AND ADMINISTRATION

2.1 Adults and adolescents 12 years of age and over

2.2 Children 6 to 11 years of age

2.3 Children 12 months to 5 years of age

2.4 Children 6 to 11 months of age

2.5 Adults with Hepatic or Renal Impairment

3 DOSAGE FORMS AND STRENGTHS

4 CONTRAINDICATIONS

5 WARNINGS AND PRECAUTIONS

5.1 Hypersensitivity Reactions

6 ADVERSE REACTIONS

6.1 Clinical Trials Experience

6.2 Post-Marketing Experience

7 DRUG INTERACTIONS

7.1 Inhibitors of Cytochrome P450 3A4

7.2 Fluoxetine

7.3 Cimetidine

8 USE IN SPECIFIC POPULATIONS

8.1 Pregnancy

8.3 Nursing Mothers

8.4 Pediatric Use

8.5 Geriatric Use

8.6 Renal Impairment

8.7 Hepatic Impairment

9 DRUG ABUSE AND DEPENDENCE

10 OVERDOSAGE

11 DESCRIPTION

12 CLINICAL PHARMACOLOGY

12.1 Mechanism of Action

12.2 Pharmacodynamics

12.3 Pharmacokinetics

13 NONCLINICAL TOXICOLOGY

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

13.2 Animal Toxicology and/or Pharmacology

14 CLINICAL STUDIES

14.1 Seasonal Allergic Rhinitis

14.2 Perennial Allergic Rhinitis

14.3 Chronic Idiopathic Urticaria

16 HOW SUPPLIED/STORAGE AND HANDLING

17 PATIENT COUNSELING INFORMATION

17.1 Information for Patients

 


FULL PRESCRIBING INFORMATION

 

 

1 INDICATIONS AND USAGE

 

1.1 Seasonal Allergic Rhinitis

CLARINEX is indicated for the relief of the nasal and non-nasal symptoms of seasonal allergic rhinitis in patients 2 years of age and older.

 

1.2 Perennial Allergic Rhinitis

CLARINEX is indicated for the relief of the nasal and non-nasal symptoms of perennial allergic rhinitis in patients 6 months of age and older.

 

1.3 Chronic Idiopathic Urticaria

CLARINEX is indicated for the symptomatic relief of pruritus, reduction in the number of hives, and size of hives, in patients with chronic idiopathic urticaria 6 months of age and older.

 

2 DOSAGE AND ADMINISTRATION

CLARINEX Tablets, Oral Solution, or RediTabs Tablets may be taken without regard to meals. Place CLARINEX (desloratadine) RediTabs Tablets on the tongue and allow to disintegrate before swallowing. Tablet disintegration occurs rapidly. Administer with or without water. Take tablet immediately after opening the blister.

The age-appropriate dose of CLARINEX Oral Solution should be administered with a commercially available measuring dropper or syringe that is calibrated to deliver 2 mL and 2.5 mL (½ teaspoon).

 

2.1 Adults and adolescents 12 years of age and over

The recommended dose of CLARINEX Tablets or CLARINEX RediTabs Tablets is one 5-mg tablet once daily. The recommended dose of CLARINEX Oral Solution is 2 teaspoonfuls (5 mg in 10 mL) once daily.

 

2.2 Children 6 to 11 years of age

The recommended dose of CLARINEX Oral Solution is 1 teaspoonful (2.5 mg in 5 mL) once daily. The recommended dose of CLARINEX RediTabs Tablets is one 2.5-mg tablet once daily.

 

2.3 Children 12 months to 5 years of age

The recommended dose of CLARINEX Oral Solution is ½ teaspoonful (1.25 mg in 2.5 mL) once daily.

 

2.4 Children 6 to 11 months of age

The recommended dose of CLARINEX Oral Solution is 2 mL (1 mg) once daily.

 

2.5 Adults with Hepatic or Renal Impairment

In adult patients with liver or renal impairment, a starting dose of one 5 mg tablet every other day is recommended based on pharmacokinetic data. Dosing recommendation for children with liver or renal impairment cannot be made due to lack of data [see Clinical Pharmacology (12.3)].

 

3 DOSAGE FORMS AND STRENGTHS

CLARINEX Tablets are light blue film coated tablets embossed with "C5" containing 5 mg desloratadine.

CLARINEX RediTabs (orally-disintegrating tablets) containing 5 mg desloratadine are light-red, flat-faced, round, speckled tablets with an "A" debossed on one side.

CLARINEX RediTabs (orally-disintegrating tablets) containing 2.5 mg desloratadine are light-red, flat-faced, round, speckled tablets with a "K" debossed on one side.

CLARINEX Oral Solution is a clear orange-colored liquid containing 0.5 mg desloratadine /1 mL

 

4 CONTRAINDICATIONS

CLARINEX Tablets, RediTabs, and Oral Solution are contraindicated in patients who are hypersensitive to this medication or to any of its ingredients or to loratadine [see Warnings and Precautions (5.1) and Adverse Reactions (6.2)].

 

5 WARNINGS AND PRECAUTIONS

 

5.1 Hypersensitivity Reactions

Hypersensitivity reactions including rash, pruritus, urticaria, edema, dyspnea, and anaphylaxis have been reported after administration of desloratadine. If such a reaction occurs, therapy with CLARINEX should be stopped and alternative treatment should be considered. [See Adverse Reactions (6.2).]

 

6 ADVERSE REACTIONS

The following adverse reactions are discussed in greater detail in other sections of the label:

 

6.1 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 rates observed in clinical practice.

 

Adults and Adolescents

 

Allergic Rhinitis: In multiple-dose placebo-controlled trials, 2,834 patients ages 12 years or older received CLARINEX Tablets at doses of 2.5 mg to 20 mg daily, of whom 1,655 patients received the recommended daily dose of 5 mg. In patients receiving 5 mg daily, the rate of adverse events was similar between CLARINEX and placebo-treated patients. The percent of patients who withdrew prematurely due to adverse events was 2.4% in the CLARINEX group and 2.6% in the placebo group. There were no serious adverse events in these trials in patients receiving desloratadine. All adverse events that were reported by greater than or equal to 2% of patients who received the recommended daily dose of CLARINEX Tablets (5 mg once daily), and that were more common with CLARINEX Tablets than placebo, are listed in Table 1.

Table 1 Incidence of Adverse Events Reported by ≥2% of Adult and Adolescent Allergic Rhinitis Patients Receiving CLARINEX Tablets
Adverse Event CLARINEX
Tablets 5 mg
(n=1,655)
Placebo

(n=1,652)
Infections and Infestations
  Pharyngitis 4.1% 2.0%
Nervous System Disorders
  Somnolence 2.1% 1.8%
Gastrointestinal Disorders
  Dry Mouth 3.0% 1.9%
Musculoskeletal and Connective Tissue Disorders
  Myalgia 2.1% 1.8%
Reproductive System and Breast Disorders
  Dysmenorrhea 2.1% 1.6%
General Disorders and Administration Site Conditions
  Fatigue 2.1% 1.2%

The frequency and magnitude of laboratory and electrocardiographic abnormalities were similar in CLARINEX and placebo-treated patients.

There were no differences in adverse events for subgroups of patients as defined by gender, age, or race.

 

Chronic Idiopathic Urticaria: In multiple-dose, placebo-controlled trials of chronic idiopathic urticaria, 211 patients ages 12 years or older received CLARINEX Tablets and 205 received placebo. Adverse events that were reported by greater than or equal to 2% of patients who received CLARINEX Tablets and that were more common with CLARINEX than placebo were (rates for CLARINEX and placebo, respectively): headache (14%, 13%), nausea (5%, 2%), fatigue (5%, 1%), dizziness (4%, 3%), pharyngitis (3%, 2%), dyspepsia (3%, 1%), and myalgia (3%, 1%).

 

Pediatrics

Two hundred and forty-six pediatric subjects 6 months to 11 years of age received CLARINEX Oral Solution for 15 days in three placebo-controlled clinical trials. Pediatric subjects aged 6 to 11 years received 2.5 mg once a day, subjects aged 1 to 5 years received 1.25 mg once a day, and subjects 6 to 11 months of age received 1.0 mg once a day.

In subjects 6 to 11 years of age, no individual adverse event was reported by 2 percent or more of the subjects.

In subjects 2 to 5 years of age, adverse events reported for CLARINEX and placebo in at least 2 percent of subjects receiving CLARINEX Oral Solution and at a frequency greater than placebo were fever (5.5%, 5.4%), urinary tract infection (3.6%, 0%) and varicella (3.6%, 0%).

In subjects 12 months to 23 months of age, adverse events reported for the CLARINEX product and placebo in at least 2 percent of subjects receiving CLARINEX Oral Solution and at a frequency greater than placebo were fever (16.9%, 12.9%), diarrhea (15.4%, 11.3%), upper respiratory tract infections (10.8%, 9.7%), coughing (10.8%, 6.5%), appetite increased (3.1%, 1.6%), emotional lability (3.1%, 0%), epistaxis (3.1%, 0%), parasitic infection (3.1%, 0%), pharyngitis (3.1%, 0%), rash maculopapular (3.1%, 0%).

In subjects 6 months to 11 months of age, adverse events reported for CLARINEX and placebo in at least 2 percent of subjects receiving CLARINEX Oral Solution and at a frequency greater than placebo were upper respiratory tract infections (21.2%, 12.9%), diarrhea (19.7%, 8.1%), fever (12.1%, 1.6%), irritability (12.1%, 11.3%), coughing (10.6%, 9.7%), somnolence (9.1%, 8.1%), bronchitis (6.1%, 0%), otitis media (6.1%, 1.6%), vomiting (6.1%, 3.2%), anorexia (4.5%, 1.6%), pharyngitis (4.5%, 1.6%), insomnia (4.5%, 0%), rhinorrhea (4.5%, 3.2%), erythema (3.0%, 1.6%), and nausea (3.0%, 0%).

There were no clinically meaningful changes in any electrocardiographic parameter, including the QTc interval. Only one of the 246 pediatric subjects receiving CLARINEX Oral Solution in the clinical trials discontinued treatment because of an adverse event.

 

6.2 Post-Marketing Experience

Because adverse events 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. The following spontaneous adverse events have been reported during the marketing of desloratadine: tachycardia, palpitations, rare cases of hypersensitivity reactions (such as rash, pruritus, urticaria, edema, dyspnea, and anaphylaxis), psychomotor hyperactivity, seizures, and elevated liver enzymes including bilirubin, and very rarely, hepatitis.

 

7 DRUG INTERACTIONS

 

7.1 Inhibitors of Cytochrome P450 3A4

In controlled clinical studies co-administration of desloratadine with ketoconazole, erythromycin, or azithromycin resulted in increased plasma concentrations of desloratadine and 3 hydroxydesloratadine, but there were no clinically relevant changes in the safety profile of desloratadine. [See Clinical Pharmacology (12.3).]

 

7.2 Fluoxetine

In controlled clinical studies co-administration of desloratadine with fluoxetine, a selective serotonin reuptake inhibitor (SSRI), resulted in increased plasma concentrations of desloratadine and 3 hydroxydesloratadine, but there were no clinically relevant changes in the safety profile of desloratadine. [See Clinical Pharmacology (12.3).]

 

7.3 Cimetidine

In controlled clinical studies co-administration of desloratadine with cimetidine, a histamine H2-receptor antagonist, resulted in increased plasma concentrations of desloratadine and 3 hydroxydesloratadine, but there were no clinically relevant changes in the safety profile of desloratadine. [See Clinical Pharmacology (12.3).]

 

8 USE IN SPECIFIC POPULATIONS

 

8.1 Pregnancy

 

Pregnancy Category C: There are no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, desloratadine should be used during pregnancy only if clearly needed.

Desloratadine was not teratogenic in rats or rabbits at approximately 210 and 230 times, respectively, the area under the concentration-time curve (AUC) in humans at the recommended daily oral dose. An increase in pre-implantation loss and a decreased number of implantations and fetuses were noted, however, in a separate study in female rats at approximately 120 times the AUC in humans at the recommended daily oral dose. Reduced body weight and slow righting reflex were reported in pups at approximately 50 times or greater than the AUC in humans at the recommended daily oral dose. Desloratadine had no effect on pup development at approximately 7 times the AUC in humans at the recommended daily oral dose. The AUCs in comparison referred to the desloratadine exposure in rabbits and the sum of desloratadine and its metabolites exposures in rats, respectively. [See Nonclinical Toxicology (13.2).]

 

8.3 Nursing Mothers

Desloratadine passes into breast milk; therefore, a decision should be made whether to discontinue nursing or to discontinue desloratadine, taking into account the benefit of the drug to the nursing mother and the possible risk to the child.

 

8.4 Pediatric Use

The recommended dose of CLARINEX Oral Solution in the pediatric population is based on cross-study comparison of the plasma concentration of CLARINEX in adults and pediatric subjects. The safety of CLARINEX Oral Solution has been established in 246 pediatric subjects aged 6 months to 11 years in three placebo-controlled clinical studies. Since the course of seasonal and perennial allergic rhinitis and chronic idiopathic urticaria and the effects of CLARINEX are sufficiently similar in the pediatric and adult populations, it allows extrapolation from the adult efficacy data to pediatric patients. The effectiveness of CLARINEX Oral Solution in these age groups is supported by evidence from adequate and well-controlled studies of CLARINEX Tablets in adults. The safety and effectiveness of CLARINEX Tablets or CLARINEX Oral Solution have not been demonstrated in pediatric patients less than 6 months of age. [See Clinical Pharmacology (12.3).]

The CLARINEX RediTabs 2.5 mg tablet has not been eva luated in pediatric patients. Bioequivalence of the CLARINEX RediTabs Tablet and the previously marketed RediTabs Tablet was established in adults. In conjunction with the dose finding studies in pediatrics described, the pharmacokinetic data for CLARINEX RediTabs supports the use of the 2.5-mg dose strength in pediatric patients 6 to 11 years of age.

 

8.5 Geriatric Use

Clinical studies of desloratadine did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy. [See Clinical Pharmacology (12.3).]

 

8.6 Renal Impairment

Dosage adjustment for patients with renal impairment is recommended [see Dosage and Administration (2.5) and Clinical Pharmacology (12.3)].

 

8.7 Hepatic Impairment

Dosage adjustment for patients with hepatic impairment is recommended [see Dosage and Administration (2.5) and Clinical Pharmacology (12.3)].

 

9 DRUG ABUSE AND DEPENDENCE

There is no information to indicate that abuse or dependency occurs with CLARINEX Tablets.

 

10 OVERDOSAGE

In the event of overdose, consider standard measures to remove any unabsorbed drug. Symptomatic and supportive treatment is recommended. Desloratadine and 3-hydroxydesloratadine are not eliminated by hemodialysis.

Information regarding acute overdosage is limited to experience from post-marketing adverse event reports and from clinical trials conducted during the development of the CLARINEX product. In a dose-ranging trial, at doses of 10 mg and 20 mg/day somnolence was reported.

In another study, no clinically relevant adverse events were reported in normal male and female volunteers who were given single daily doses of CLARINEX 45 mg for 10 days [See Clinical Pharmacology (12.2)].

Lethality occurred in rats at oral doses of 250 mg/kg or greater (estimated desloratadine and desloratadine metabolite exposures were approximately 120 times the AUC in humans at the recommended daily oral dose). The oral median lethal dose in mice was 353 mg/kg (estimated desloratadine exposures were approximately 290 times the human daily oral dose on a mg/m2 basis). No deaths occurred at oral doses up to 250 mg/kg in monkeys (estimated desloratadine exposures were approximately 810 times the human daily oral dose on a mg/m2 basis).

 

11 DESCRIPTION

CLARINEX (desloratadine) Tablets are light blue, round, film-coated tablets containing 5 mg desloratadine, an antihistamine, to be administered orally. CLARINEX Tablets also contain the following excipients: dibasic calcium phosphate dihydrate USP, microcrystalline cellulose NF, corn starch NF, talc USP, carnauba wax NF, white wax NF, coating material consisting of lactose monohydrate, hypromellose, titanium dioxide, polyethylene glycol, and FD&C Blue #2 Aluminum Lake.

CLARINEX Oral Solution is a clear orange-colored liquid containing 0.5 mg/1 mL desloratadine. The Oral Solution contains the following inactive ingredients: propylene glycol USP, sorbitol solution USP, citric acid (anhydrous) USP, sodium citrate dihydrate USP, sodium benzoate NF, disodium edetate USP, purified water USP. It also contains granulated sugar, natural and artificial flavor for bubble gum, and FDC Yellow #6 dye.

The CLARINEX RediTabs® brand of desloratadine orally-disintegrating tablets are light red, flat-faced, round, speckled tablets with an "A" debossed on one side for the 5 mg tablets and a "K" debossed on one side for the 2.5 mg tablets. Each RediTabs Tablet contains either 5 mg or 2.5 mg of desloratadine. It also contains the following inactive ingredients: mannitol USP, microcrystalline cellulose NF, pregelatinized starch NF, sodium starch glycolate USP, magnesium stearate NF, butylated methacrylate copolymer, crospovidone NF, aspartame NF, citric acid USP, sodium bicarbonate USP, colloidal silicon dioxide NF, ferric oxide red NF, and tutti frutti flavoring.

Desloratadine is a white to off-white powder that is slightly soluble in water, but very soluble in ethanol and propylene glycol. It has an empirical formula: C19H19ClN2 and a molecular weight of 310.8. The chemical name is 8-chloro-6,11-dihydro-11-(4-piperdinylidene)-5H-benzo[5,6]cyclohepta[1,2-b]pyridine and has the following structure:

Chemical Structure

 

12 CLINICAL PHARMACOLOGY

 

12.1 Mechanism of Action

Desloratadine is a long-acting tricyclic histamine antagonist with selective H1-receptor histamine antagonist activity. Receptor binding data indicates that at a concentration of 2–3 ng/mL (7 nanomolar), desloratadine shows significant interaction with the human histamine H1-receptor. Desloratadine inhibited histamine release from human mast cells in vitro. Results of a radiolabeled tissue distribution study in rats and a radioligand H1-receptor binding study in guinea pigs showed that desloratadine did not readily cross the blood brain barrier. The clinical significance of this finding is unknown.

 

12.2 Pharmacodynamics

 

Wheal and Flare: Human histamine skin wheal studies following single and repeated 5-mg doses of desloratadine have shown that the drug exhibits an antihistaminic effect by 1 hour; this activity may persist for as long as 24 hours. There was no evidence of histamine-induced skin wheal tachyphylaxis within the desloratadine 5-mg group over the 28-day treatment period. The clinical relevance of histamine wheal skin testing is unknown.

 

Effects on QTc: Single daily doses of 45 mg were given to normal male and female volunteers for 10 days. All ECGs obtained in this study were manually read in a blinded fashion by a cardiologist. In CLARINEX-treated subjects, there was an increase in mean heart rate of 9.2 bpm relative to placebo. The QT interval was corrected for heart rate (QTc) by both the Bazett and Fridericia methods. Using the QTc (Bazett) there was a mean increase of 8.1 msec in CLARINEX-treated subjects relative to placebo. Using QTc (Fridericia) there was a mean increase of 0.4 msec in CLARINEX-treated subjects relative to placebo. No clinically relevant adverse events were reported.

 

12.3 Pharmacokinetics

 

Absorption

Following oral administration of a desloratadine 5 mg tablet once daily for 10 days to normal healthy volunteers, the mean time to maximum plasma concentrations (Tmax) occurred at approximately 3 hours post dose and mean steady state peak plasma concentrations (Cmax) and AUC of 4 ng/mL and 56.9 ng∙hr/mL were observed, respectively. Neither food nor grapefruit juice had an effect on the bioavailability (Cmax and AUC) of desloratadine.

The pharmacokinetic profile of CLARINEX Oral Solution was eva luated in a three-way crossover study in 30 adult volunteers. A single dose of 10 mL of CLARINEX Oral Solution containing 5 mg of desloratadine was bioequivalent to a single dose of 5 mg CLARINEX Tablet. Food had no effect on the bioavailability (AUC and Cmax) of CLARINEX Oral Solution.

The pharmacokinetic profile of CLARINEX RediTabs Tablets was eva luated in a three way crossover study in 24 adult volunteers. A single CLARINEX RediTabs Tablet containing 5 mg of desloratadine was bioequivalent to a single 5 mg CLARINEX RediTabs Tablet (original formulation) for both desloratadine and 3-hydroxydesloratadine. Food and water had no effect on the bioavailability (AUC and Cmax) of CLARINEX RediTabs Tablets.

 

Distribution

Desloratadine and 3-hydroxydesloratadine are approximately 82% to 87% and 85% to 89% bound to plasma proteins, respectively. Protein binding of desloratadine and 3-hydroxydesloratadine was unaltered in subjects with impaired renal function.

 

Metabolism

Desloratadine (a major metabolite of loratadine) is extensively metabolized to 3-hydroxydesloratadine, an active metabolite, which is subsequently glucuronidated. The enzyme(s) responsible for the formation of 3-hydroxydesloratadine have not been identified. Data from clinical trials indicate that a subset of the general population has a decreased ability to form 3-hydroxydesloratadine, and are poor metabolizers of desloratadine. In pharmacokinetic studies (n=3,748), approximately 6% of subjects were poor metabolizers of desloratadine (defined as a subject with an AUC ratio of 3-hydroxydesloratadine to desloratadine less than 0.1, or a subject with a desloratadine half-life exceeding 50 hours). These pharmacokinetic studies included subjects between the ages of 2 and 70 years, including 977 subjects aged 2 to 5 years, 1,575 subjects aged 6 to 11 years, and 1196 subjects aged 12 to 70 years. There was no difference in the preva lence of poor metabolizers across age groups. The frequency of poor metabolizers was higher in Blacks (17%, n=988) as compared to Caucasians (2%, n=1,462) and Hispanics (2%, n=1,063). The median exposure (AUC) to desloratadine in the poor metabolizers was approximately 6-fold greater than in the subjects who are not poor metabolizers. Subjects who are poor metabolizers of desloratadine cannot be prospectively identified and will be exposed to higher levels of desloratadine following dosing with the recommended dose of desloratadine. In multidose clinical safety studies, where metabolizer status was identified, a total of 94 poor metabolizers and 123 normal metabolizers were enrolled and treated with CLARINEX Oral Solution for 15–35 days. In these studies, no overall differences in safety were observed between poor metabolizers and normal metabolizers. Although not seen in these studies, an increased risk of exposure-related adverse events in patients who are poor metabolizers cannot be ruled out.

 

Elimination

The mean plasma elimination half-life of desloratadine was approximately 27 hours. Cmax and AUC values increased in a dose proportional manner following single oral doses between 5 and 20 mg. The degree of accumulation after 14 days of dosing was consistent with the half-life and dosing frequency. A human mass balance study documented a recovery of approximately 87% of the 14C-desloratadine dose, which was equally distributed in urine and feces as metabolic products. Analysis of plasma 3-hydroxydesloratadine showed similar Tmax and half-life values compared to desloratadine.

 

Special Populations

 

Geriatric Subjects: In older subjects (≥65 years old; n=17) following multiple-dose administration of CLARINEX Tablets, the mean Cmax and AUC values for desloratadine were 20% greater than in younger subjects (<65 years old). The oral total body clearance (CL/F) when normalized for body weight was similar between the two age groups. The mean plasma elimination half-life of desloratadine was 33.7 hr in subjects ≥65 years old. The pharmacokinetics for 3-hydroxydesloratadine appeared unchanged in older versus younger subjects. These age-related differences are unlikely to be clinically relevant and no dosage adjustment is recommended in elderly subjects.

 

Pediatric Subjects: In subjects 6 to 11 years old, a single dose of 5 mL of CLARINEX Oral Solution containing 2.5 mg of desloratadine, resulted in desloratadine plasma concentrations similar to those achieved in adults administered a single 5 mg CLARINEX Tablet. In subjects 2 to 5 years old, a single dose of 2.5 mL of CLARINEX Oral Solution containing 1.25 mg of desloratadine, resulted in desloratadine plasma concentrations similar to those achieved in adults administered a single 5-mg CLARINEX Tablet. However, the Cmax and AUC of the metabolite (3-hydroxydesloratadine) were 1.27 and 1.61 times higher for the 5 mg dose of Oral Solution administered in adults compared to the Cmax and AUC obtained in children 2 to 11 years of age receiving 1.25–2.5 mg of CLARINEX Oral Solution.

A single dose of either 2.5 mL or 1.25 mL of CLARINEX Oral Solution containing 1.25 mg or 0.625 mg, respectively, of desloratadine was administered to subjects 6 to 11 months of age and 12 to 23 months of age. The results of a population pharmacokinetic analysis indicated that a dose of 1 mg for subjects aged 6 to 11 months and 1.25 mg for subjects 12 to 23 months of age is required to obtain desloratadine plasma concentrations similar to those achieved in adults administered a single 5 mg dose of CLARINEX Oral Solution.

The CLARINEX RediTabs 2.5 mg tablet has not been eva luated in pediatric patients. Bioequivalence of the CLARINEX RediTabs Tablet and the original CLARINEX RediTabs Tablets was established in adults. In conjunction with the dose-finding studies in pediatrics described, the pharmacokinetic data for CLARINEX RediTabs Tablets supports the use of the 2.5-mg dose strength in pediatric patients 6 to 11 years of age.

 

Renally Impaired: Desloratadine pharmacokinetics following a single dose of 7.5 mg were characterized in patients with mild (n=7; creatinine clearance 51–69 mL/min/1.73 m2), moderate (n=6; creatinine clearance 34–43 mL/min/1.73 m2), and severe (n=6; creatinine clearance 5–29 mL/min/1.73 m2) renal impairment or hemodialysis dependent (n=6) patients. In patients with mild and moderate renal impairment, median Cmax and AUC values increased by approximately 1.2- and 1.9-fold, respectively, relative to subjects with normal renal function. In patients with severe renal impairment or who were hemodialysis dependent, Cmax and AUC values increased by approximately 1.7- and 2.5-fold, respectively. Minimal changes in 3-hydroxydesloratadine concentrations were observed. Desloratadine and 3-hydroxydesloratadine were poorly removed by hemodialysis. Plasma protein binding of desloratadine and 3-hydroxydesloratadine was unaltered by renal impairment. Dosage adjustment for patients with renal impairment is recommended [see Dosage and Administration (2.5)].

 

Hepatically Impaired: Desloratadine pharmacokinetics were characterized following a single oral dose in patients with mild (n=4), moderate (n=4), and severe (n=4) hepatic impairment as defined by the Child-Pugh classification of hepatic function and 8 subjects with normal hepatic function. Patients with hepatic impairment, regardless of severity, had approximately a 2.4-fold increase in AUC as compared with normal subjects. The apparent oral clearance of desloratadine in patients with mild, moderate, and severe hepatic impairment was 37%, 36%, and 28% of that in normal subjects, respectively. An increase in the mean elimination half-life of desloratadine in patients with hepatic impairment was observed. For 3-hydroxydesloratadine, the mean Cmax and AUC values for patients with hepatic impairment were not statistically significantly different from subjects with normal hepatic function. Dosage adjustment for patients with hepatic impairment is recommended [see Dosage and Administration (2.5)].

 

Gender: Female subjects treated for 14 days with CLARINEX Tablets had 10% and 3% higher desloratadine Cmax and AUC values, respectively, compared with male subjects. The 3-hydroxydesloratadine Cmax and AUC values were also increased by 45% and 48%, respectively, in females compared with males. However, these apparent differences are not likely to be clinically relevant and therefore no dosage adjustment is recommended.

 

Race: Following 14 days of treatment with CLARINEX Tablets, the Cmax and AUC values for desloratadine were 18% and 32% higher, respectively, in Blacks compared with Caucasians. For 3-hydroxydesloratadine there was a corresponding 10% reduction in Cmax and AUC values in Blacks compared to Caucasians. These differences are not likely to be clinically relevant and therefore no dose adjustment is recommended.

 

Drug Interactions: In two controlled crossover clinical pharmacology studies in healthy male (n=12 in each study) and female (n=12 in each study) volunteers, desloratadine 7.5 mg (1.5 times the daily dose) once daily was coadministered with erythromycin 500 mg every 8 hours or ketoconazole 200 mg every 12 hours for 10 days. In three separate controlled, parallel group clinical pharmacology studies, desloratadine at the clinical dose of 5 mg has been coadministered with azithromycin 500 mg followed by 250 mg once daily for 4 days (n=18) or with fluoxetine 20 mg once daily for 7 days after a 23-day pretreatment period with fluoxetine (n=18) or with cimetidine 600 mg every 12 hours for 14 days (n=18) under steady-state conditions to normal healthy male and female volunteers. Although increased plasma concentrations (Cmax and AUC 0–24 hrs) of desloratadine and 3-hydroxydesloratadine were observed (see Table 2), there were no clinically relevant changes in the safety profile of desloratadine, as assessed by electrocardiographic parameters (including the corrected QT interval), clinical laboratory tests, vital signs, and adverse events.

Table 2 Changes in Desloratadine and 3-Hydroxydesloratadine Pharmacokinetics in Healthy Male and Female Volunteers
  Desloratadine 3-Hydroxydesloratadine
  Cmax AUC
0–24 hrs
Cmax AUC
0–24 hrs
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