Paliperidone

12.1 Mechanism of Action Paliperidone is the major active metabolite of risperidone. The mechanism of action of paliperidone in schizophrenia is unclear. However, the drug's therapeutic effect in schizophrenia could be mediated through a combination of central dopamine Type 2 (D 2 ) and serotonin Type 2 (5HT 2A ) receptor antagonism.

1 INDICATIONS AND USAGE Paliperidone extended-release tablets are an atypical antipsychotic agent indicated for Treatment of schizophrenia (1.1) Adults: Efficacy was established in three 6-week trials and one maintenance trial. (14.1) Adolescents (ages 12 to 17): Efficacy was established in one 6-week trial. (14.1) Treatment of schizoaffective disorder as monotherapy and as an adjunct to mood stabilizers and/or antidepressants. (1.2) Efficacy was established in two 6-week trials in adult patients. (14.2) 1.1 Schizophrenia Paliperidone extended-release tablets are indicated for the treatment of schizophrenia [see Clinical Studies (14.1) ]. The efficacy of paliperidone extended-release tablets in schizophrenia was established in three 6-week trials in adults and one 6-week trial in adolescents, as well as one maintenance trial in adults. 1.2 Schizoaffective Disorder Paliperidone extended-release tablets are indicated for the treatment of schizoaffective disorder as monotherapy and an adjunct to mood stabilizers and/or antidepressant therapy [see Clinical Studies (14.2) ] . The efficacy of paliperidone in schizoaffective disorder was established in two 6-week trials in adults.

2 DOSAGE AND ADMINISTRATION Initial Dose Recommended Dose Maximum Dose Schizophrenia - adults (2.1) 6 mg/day 3 to 12 mg/day 12 mg/day Schizophrenia-adolescents (2.1) Weight < 51 kg 3 mg/day 3 to 6 mg/day 6 mg/day Weight ≥ 51 kg 3 mg/day 3 to 12 mg/day 12 mg/day Schizoaffective disorder - adults (2.2) 6 mg/day 3 to 12 mg/day 12 mg/day Tablet should be swallowed whole and should not be chewed, divided, or crushed. (2.3) 2.1 Schizophrenia Adults The recommended dose of paliperidone extended-release tablets for the treatment of schizophrenia in adults is 6 mg administered once daily. Initial dose titration is not required. Although it has not been systematically established that doses above 6 mg have additional benefit, there was a general trend for greater effects with higher doses. This must be weighed against the dose-related increase in adverse reactions. Thus, some patients may benefit from higher doses, up to 12 mg/day, and for some patients, a lower dose of 3 mg/day may be sufficient. Dose increases above 6 mg/day should be made only after clinical reassessment and generally should occur at intervals of more than 5 days. When dose increases are indicated, increments of 3 mg/day are recommended. The maximum recommended dose is 12 mg/day. In a longer-term study, paliperidone extended-release tablets have been shown to be effective in delaying time to relapse in patients with schizophrenia who were stabilized on paliperidone extended-release tablets for 6 weeks [see Clinical Studies (14) ]. Paliperidone extended-release tablets should be prescribed at the lowest effective dose for maintaining clinical stability and the physician should periodically reevaluate the long-term usefulness of the drug in individual patients. Adolescents (12 to 17 years of age) The recommended starting dose of paliperidone extended-release tablets for the treatment of schizophrenia in adolescents 12 to 17 years of age is 3 mg administered once daily. Initial dose titration is not required. Dose increases, if considered necessary, should be made only after clinical reassessment and should occur at increments of 3 mg/day at intervals of more than 5 days. Prescribers should be mindful that, in the adolescent schizophrenia study, there was no clear enhancement to efficacy at the higher doses, i.e., 6 mg for subjects weighing less than 51 kg and 12 mg for subjects weighing 51 kg or greater, while adverse events were dose-related. 2.2 Schizoaffective Disorder The recommended dose of paliperidone extended-release tablets for the treatment of schizoaffective disorder in adults is 6 mg administered once daily. Initial dose titration is not required. Some patients may benefit from lower or higher doses within the recommended dose range of 3 to 12 mg once daily. A general trend for greater effects was seen with higher doses. This trend must be weighed against dose-related increase in adverse reactions. Dosage adjustment, if indicated, should occur only after clinical reassessment. Dose increases, if indicated, generally should occur at intervals of more than 4 days. When dose increases are indicated, increments of 3 mg/day are recommended. The maximum recommended dose is 12 mg/day. 2.3 Administration Instructions Paliperidone extended-release tablets can be taken with or without food. Paliperidone extended-release tablets must be swallowed whole with the aid of liquids. Tablets should not be chewed, divided, or crushed. The medication is contained within a nonabsorbable shell designed to release the drug at a controlled rate. The tablet shell, along with insoluble core components, is eliminated from the body; patients should not be concerned if they occasionally notice in their stool something that looks like a tablet. 2.4 Use with Risperidone Concomitant use of paliperidone extended-release tablets with risperidone has not been studied. Since paliperidone is the major active metabolite of risperidone, consideration should be given to the additive paliperidone exposure if risperidone is co-administered with paliperidone extended-release tablets. 2.5 Dosage in Special Populations Renal Impairment Dosing must be individualized according to the patient’s renal function status. For patients with mild renal impairment (creatinine clearance ≥ 50 mL/min to < 80 mL/min), the recommended initial dose of paliperidone extended-release tablets is 3 mg once daily. The dose may then be increased to a maximum of 6 mg once daily based on clinical response and tolerability. For patients with moderate to severe renal impairment (creatinine clearance ≥ 10 mL/min to < 50 mL/min), the recommended initial dose of paliperidone extended-release tablets is 1.5 mg once daily, which may be increased to a maximum of 3 mg once daily after clinical reassessment. As paliperidone extended-release tablets have not been studied in patients with creatinine clearance below 10 mL/min, use is not recommended in such patients [see Clinical Pharmacology (12.3) ] . Hepatic Impairme

6 ADVERSE REACTIONS The following adverse reactions are discussed in more detail in other sections of the labeling: Increased mortality in elderly patients with dementia-related psychosis [see Boxed Warning and Warnings and Precautions (5.1) ] Cerebrovascular adverse reactions, including stroke, in elderly patients with dementia-related psychosis [see Warnings and Precautions (5.2) ] Neuroleptic malignant syndrome [see Warnings and Precautions (5.3) ] QT prolongation [see Warnings and Precautions (5.4) ] Tardive dyskinesia [see Warnings and Precautions (5.5) ] Metabolic changes [see Warnings and Precautions (5.6) ] Hyperprolactinemia [see Warnings and Precautions (5.7) ] Potential for gastrointestinal obstruction [see Warnings and Precautions (5.8) ] Orthostatic hypotension and syncope [see Warnings and Precautions (5.9) ] Falls [see Warnings and Precautions (5.10) ] Leukopenia, neutropenia, and agranulocytosis [see Warnings and Precautions (5.11) ] Potential for cognitive and motor impairment [see Warnings and Precautions (5.12) ] Seizures [see Warnings and Precautions (5.13) ] Dysphagia [see Warnings and Precautions (5.14) ] Priapism [see Warnings and Precautions (5.15) ] Disruption of body temperature regulation [see Warnings and Precautions (5.16) ] Commonly observed adverse reactions (incidence ≥ 5% and at least twice that for placebo) were (6) Adults with schizophrenia: extrapyramidal symptoms, tachycardia, and akathisia. Adolescents with schizophrenia: somnolence, akathisia, tremor, dystonia, cogwheel rigidity, anxiety, weight increased, and tachycardia. Adults with schizoaffective disorder: extrapyramidal symptoms, somnolence, dyspepsia, constipation, weight increased, and nasopharyngitis. To report SUSPECTED ADVERSE REACTIONS, contact AvKARE at 1-855-361-3993 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch 6.1 Clinical Trials Experience The most common adverse reactions in clinical trials in adult subjects with schizophrenia (reported in 5% or more of subjects treated with paliperidone and at least twice the placebo rate in any of the dose groups) were extrapyramidal symptoms, tachycardia, and akathisia. The most common adverse reactions in clinical trials in adult patients with schizoaffective disorder (reported in 5% or more of subjects treated with paliperidone and at least twice the placebo rate) were extrapyramidal symptoms, somnolence, dyspepsia, constipation, weight increased, and nasopharyngitis. The most common adverse reactions that were associated with discontinuation from clinical trials in adult subjects with schizophrenia (causing discontinuation in 2% of paliperidone-treated subjects) were nervous system disorders. The most common adverse reactions that were associated with discontinuation from clinical trials in adult subjects with schizoaffective disorder were gastrointestinal disorders, which resulted in discontinuation in 1% of paliperidone-treated subjects [see Adverse Reactions (6) ]. The safety of paliperidone was evaluated in 1205 adult subjects with schizophrenia who participated in three placebo-controlled, 6-week, double-blind trials, of whom 850 subjects received paliperidone at fixed doses ranging from 3 mg to 12 mg once daily. The information presented in this section was derived from pooled data from these three trials. Additional safety information from the placebo-controlled phase of the long-term maintenance study, in which subjects received paliperidone at daily doses within the range of 3 mg to 15 mg (n=104), is also included. The safety of paliperidone was evaluated in 150 adolescent subjects 12 to 17 years of age with schizophrenia who received paliperidone in the dose range of 1.5 mg to 12 mg/day in a 6-week, double-blind, placebo-controlled trial. The safety of paliperidone was also evaluated in 622 adult subjects with schizoaffective disorder who participated in two placebo-controlled, 6-week, double-blind trials. In one of these trials, 206 subjects were assigned to one of two dose levels of paliperidone: 6 mg with the option to reduce to 3 mg (n = 108) or 12 mg with the option to reduce to 9 mg (n = 98) once daily. In the other study, 214 subjects received flexible doses of paliperidone (3 to 12 mg once daily). Both studies included subjects who received paliperidone either as monotherapy or as an adjunct to mood stabilizers and/or antidepressants. Adverse events during exposure to study treatment were obtained by general inquiry and recorded by clinical investigators using their own terminology. Consequently, to provide a meaningful estimate of the proportion of individuals experiencing adverse events, events were grouped in standardized categories using MedDRA terminology. Throughout this section, adverse reactions are reported. Adverse reactions are adverse events that were considered to be reasonably associated with the use of paliperidone (adverse drug reactions) based on the comprehensive assessment of the available adverse event information. A causa

7 DRUG INTERACTIONS Centrally-acting drugs: Due to CNS effects, use caution in combination. Avoid alcohol. (7.1) Drugs that may cause orthostatic hypotension: An additive effect may be observed when co-administered with paliperidone. (7.1) Strong CYP3A4/P-glycoprotein (P-gp) inducers: It may be necessary to increase the dose of paliperidone when a strong inducer of both CYP3A4 and P-gp (e.g., carbamazepine) is co-administered. Conversely, on discontinuation of the strong inducer, it may be necessary to decrease the dose of paliperidone. (7.2) Co-administration of divalproex sodium increased C max and AUC of paliperidone by approximately 50%. Adjust dose of paliperidone if necessary based on clinical assessment. (7.2) 7.1 Potential for Paliperidone to Affect Other Drugs Given the primary CNS effects of paliperidone [see Adverse Reactions (6.1, 6.2) ] , paliperidone should be used with caution in combination with other centrally acting drugs and alcohol. Paliperidone may antagonize the effect of levodopa and other dopamine agonists. Because of its potential for inducing orthostatic hypotension, an additive effect may be observed when paliperidone is administered with other therapeutic agents that have this potential [see Warnings and Precautions (5.9) ]. Paliperidone is not expected to cause clinically important pharmacokinetic interactions with drugs that are metabolized by cytochrome P450 isozymes. In vitro studies in human liver microsomes showed that paliperidone does not substantially inhibit the metabolism of drugs metabolized by cytochrome P450 isozymes, including CYP1A2, CYP2A6, CYP2C8/9/10, CYP2D6, CYP2E1, CYP3A4, and CYP3A5. Therefore, paliperidone is not expected to inhibit clearance of drugs that are metabolized by these metabolic pathways in a clinically relevant manner. Paliperidone is also not expected to have enzyme inducing properties. Paliperidone is a weak inhibitor of P-glycoprotein (P-gp) at high concentrations. No in vivo data are available and the clinical relevance is unknown. Pharmacokinetic interaction between lithium and paliperidone is unlikely. In a drug interaction study, co-administration of paliperidone (12 mg once daily for 5 days) with divalproex sodium extended-release tablets (500 mg to 2000 mg once daily) did not affect the steady-state pharmacokinetics (AUC 24h and C max,ss ) of valproate in 13 patients stabilized on valproate. In a clinical study, subjects on stable doses of valproate had comparable valproate average plasma concentrations when paliperidone 3 to 15 mg/day was added to their existing valproate treatment. 7.2 Potential for Other Drugs to Affect Paliperidone Paliperidone is not a substrate of CYP1A2, CYP2A6, CYP2C9, and CYP2C19, so that an interaction with inhibitors or inducers of these isozymes is unlikely. While in vitro studies indicate that CYP2D6 and CYP3A4 may be minimally involved in paliperidone metabolism, in vivo studies do not show decreased elimination by these isozymes and they contribute to only a small fraction of total body clearance. In vitro studies have shown that paliperidone is a P-gp substrate. Co-administration of paliperidone 6 mg once daily with carbamazepine, a strong inducer of both CYP3A4 and P-glycoprotein (P-gp), at 200 mg twice daily caused a decrease of approximately 37% in the mean steady-state C max and AUC of paliperidone. This decrease is caused, to a substantial degree, by a 35% increase in renal clearance of paliperidone. A minor decrease in the amount of drug excreted unchanged in the urine suggests that there was little effect on the CYP metabolism or bioavailability of paliperidone during carbamazepine co-administration. On initiation of carbamazepine, the dose of paliperidone should be re-evaluated and increased if necessary. Conversely, on discontinuation of carbamazepine, the dose of paliperidone should be re-evaluated and decreased if necessary. Paliperidone is metabolized to a limited extent by CYP2D6 [see Clinical Pharmacology (12.3) ] . In an interaction study in healthy subjects in which a single 3 mg dose of paliperidone was administered concomitantly with 20 mg per day of paroxetine (a potent CYP2D6 inhibitor), paliperidone exposures were on average 16% (90% CI: 4, 30) higher in CYP2D6 extensive metabolizers. Higher doses of paroxetine have not been studied. The clinical relevance is unknown. Co-administration of a single dose of paliperidone 12 mg with divalproex sodium extended-release tablets (two 500 mg tablets once daily) resulted in an increase of approximately 50% in the C max and AUC of paliperidone. Dosage reduction for paliperidone should be considered when paliperidone is co-administered with valproate after clinical assessment. Pharmacokinetic interaction between lithium and paliperidone is unlikely.