Not applicable.
Celecoxib at oral doses >150 mg/kg/day (approximately 2-fold human exposure at 200 mg twice daily as measured by AUC0-24), caused an increased incidence of ventricular septal defects, a rare event, and fetal alterations, such as ribs fused, sternebrae fused and sternebrae misshapen when rabbits were treated throughout organogenesis. A dose-dependent increase in diaphragmatic hernias was observed when rats were given celecoxib at oral doses >30 mg/kg/day (approximately 6-fold human exposure based on the AUC0-24 at 200 mg twice daily) throughout organogenesis. These effects are expected following inhibition of prostaglandin synthesis. In rats, exposure to celecoxib during early embryonic development resulted in pre-implantation and post-implantation losses, and reduced embryo/fetal survival.
Celecoxib was excreted in rat milk. In a peri-post natal study in rats, pup toxicity was observed.
In a 2 year toxicity study an increase in nonadrenal thrombosis was observed in male rat at high doses.
Conventional embryo-fetal toxicity studies resulted in dose dependent occurrences of diaphragmatic hernia in rat fetuses and of cardiovascular malformations in rabbit fetuses at systemic exposures to free drug approximately 5X (rat) and 3X (rabbit) higher than those achieved at the maximum recommended daily human dose (400 mg). Diaphragmatic hernia was also seen in a peri-post natal toxicity study in rats, which included exposure during the organogenetic period. In the latter study, at the lowest systemic exposure where this anomaly occurred in a single animal, the estimated margin relative to the maximum recommended daily human dose was 3X.
In animals, exposure to Celebra during early embryonic development resulted in pre-implantation and post-implantation losses. These effects are expected following inhibition of prostaglandin synthesis.
Celebra was excreted in rat milk. In a peri-post natal study in rats, pup toxicity was observed.
Based on conventional studies, genotoxicity or carcinogenicity, no special hazard for humans was observed, beyond those addressed in other sections of the SmPC. In a two-year toxicity study an increase in nonadrenal thrombosis was observed in male rat at high doses.
Absorption
Celecoxib is well absorbed reaching peak plasma concentrations after approximately 2-3 hours. Dosing with food (high fat meal) delays absorption of celecoxib by about 1 hour resulting in a Tmax of about 4 hours and increases bioavailability by about 20%.
In healthy adult volunteers, the overall systemic exposure (AUC) of celecoxib was equivalent when celecoxib was administered as intact capsule or capsule contents sprinkled on applesauce. There were no significant alterations in Cmax, Tmax or T1/2 after administration of capsule contents on applesauce.
Distribution
Plasma protein binding is about 97 % at therapeutic plasma concentrations and the medicinal product is not preferentially bound to erythrocytes.
Biotransformation
Celecoxib metabolism is primarily mediated via cytochrome P450 2C9. Three metabolites, inactive as COX-1 or COX-2 inhibitors, have been identified in human plasma i.e., a primary alcohol, the corresponding carboxylic acid and its glucuronide conjugate.
Cytochrome P450 2C9 activity is reduced in individuals with genetic polymorphisms that lead to reduced enzyme activity, such as those homozygous for the CYP2C9*3 polymorphism.
In a pharmacokinetic study of celecoxib 200 mg administered once daily in healthy volunteers, genotyped as either CYP2C9*1/*1, CYP2C9*1/*3, or CYP2C9*3/*3, the median Cmax and AUC0-24 of celecoxib on day 7 were approximately 4-fold and 7-fold, respectively, in subjects genotyped as CYP2C9*3/*3 compared to other genotypes. In three separate single dose studies, involving a total of 5 subjects genotyped as CYP2C9*3/*3, single-dose AUC0-24 increased by approximately 3-fold compared to normal metabolisers. It is estimated that the frequency of the homozygous *3/*3 genotype is 0.3-1.0% among different ethnic groups.
Patients who are known, or suspected to be CYP2C9 poor metabolisers based on previous history/experience with other CYP2C9 substrates should be administered celecoxib with caution.
No clinically significant differences were found in PK parameters of celecoxib between elderly African-Americans and Caucasians.
The plasma concentration of celecoxib is approximately 100% increased in elderly women (>65 years).
Compared to subjects with normal hepatic function, patients with mild hepatic impairment had a mean increase in Cmax of 53% and in AUC of 26% of celecoxib. The corresponding values in patients with moderate hepatic impairment were 41% and 146% respectively. The metabolic capacity in patients with mild to moderate impairment was best correlated to their albumin values. Treatment should be initiated at half the recommended dose in patients with moderate liver impairment (with serum albumin 25-35 g/l). Patients with severe hepatic impairment (serum albumin <25 g/l) have not been studied and celecoxib is contraindicated in this patient group.
There is little experience of celecoxib in renal impairment. The pharmacokinetics of celecoxib has not been studied in patients with renal impairment but is unlikely to be markedly changed in these patients. Thus caution is advised when treating patients with renal impairment. Severe renal impairment is contraindicated.
Elimination
Celecoxib is mainly eliminated by metabolism. Less than 1 % of the dose is excreted unchanged in urine. The inter-subject variability in the exposure of celecoxib is about 10-fold. Celecoxib exhibits dose- and time-independent pharmacokinetics in the therapeutic dose range. Elimination half-life is 8-12 hours. Steady state plasma concentrations are reached within 5 days of treatment.
Absorption
Celebra is well absorbed reaching peak plasma concentrations after approximately 2-3 hours. Dosing with food (high fat meal) delays absorption by about 1 hour.
Distribution
The inter-subject variability in the exposure of Celebra is about 10-fold. Celebra exhibits dose- and time-independent pharmacokinetics in the therapeutic dose range. Plasma protein binding is about 97% at therapeutic plasma concentrations and the drug is not preferentially bound to erythrocytes. Elimination half-life is 8-12 hours. Steady state plasma concentrations are reached within 5 days of treatment. Pharmacological activity resides in the parent drug. The main metabolites found in the circulation have no detectable COX-1 or COX-2 activity.
Biotransformation
Celebra metabolism is primarily mediated via cytochrome P450 2C9. Three metabolites, inactive as COX-1 or COX-2 inhibitors, have been identified in human plasma i.e., a primary alcohol, the corresponding carboxylic acid and its glucuronide conjugate.
Cytochrome P450 2C9 activity is reduced in individuals with genetic polymorphisms that lead to reduced enzyme activity, such as those homozygous for the CYP2C9*3 polymorphism.
In a pharmacokinetic study of Celebra 200 mg administered once daily in healthy volunteers, genotyped as either CYP2C9*1/*1, CYP2C9*1/*3, or CYP2C9*3/*3, the median Cmax and AUC 0-24 of Celebra on day 7 were approximately 4-fold and 7- fold, respectively, in subjects genotyped as CYP2C9*3/*3 compared to other genotypes. In three separate single dose studies, involving a total of 5 subjects genotyped as CYP2C9*3/*3, single-dose AUC 0-24 increased by approximately 3- fold compared to normal metabolizers. It is estimated that the frequency of the homozygous *3/*3 genotype is 0.3-1.0% among different ethnic groups.
Patients who are known, or suspected to be CYP2C9 poor metabolizers based on previous history/experience with other CYP2C9 substrates should be administered Celebra with caution.
Elimination
Celebra is mainly eliminated by metabolism. Less than 1% of the dose is excreted unchanged in urine.
Renal impairment
There is little experience of Celebra in renal impairment. The pharmacokinetics of Celebra has not been studied in patients with renal impairment but is unlikely to be markedly changed in these patients. Thus caution is advised when treating patients with renal impairment. Severe renal impairment is contraindicated.
Hepatic impairment
Compared to subjects with normal hepatic function, patients with mild hepatic impairment had a mean increase in Cmax of 53% and in AUC of 26% of Celebra. The corresponding values in patients with moderate hepatic impairment were 41% and 146% respectively. The metabolic capacity in patients with mild to moderate impairment was best correlated to their albumin values. Treatment should be initiated at half the recommended dose in patients with moderate liver impairment (with serum albumin 25-35g/L). Patients with severe hepatic impairment (serum albumin <25 g/l) have not been studied and Celebra is contraindicated in this patient group.
Elderly
No clinically significant differences were found in PK parameters of Celebra between elderly African-Americans and Caucasians.
The plasma concentration of Celebra is approximately 100% increased in elderly women (>65 years).
Any unused medicinal product or waste material should be disposed of in accordance with local requirements.
No special requirements for disposal.
Any unused medicinal product or waste material should be disposed of in accordance with local requirements.
