Paliperidone Palmitate

Paliperidone Palmitate is an atypical antipsychotic indicated for

• Treatment of schizophrenia in adults.
• Treatment of schizoaffective disorder in adults as monotherapy and as an adjunct to mood stabilizers or antidepressants.

Paliperidone palmitate is hydrolyzed to paliperidone. Paliperidone is the major active metabolite of risperidone. The mechanism of action of paliperidone is unclear. However, the drug’s therapeutic effect in schizophrenia could be mediated through a combination of central dopamine Type 2 (D2 ) and serotonin Type 2 (5HT 2A ) receptor antagonism.

In vitro, paliperidone acts as an antagonist at the central dopamine Type 2 (D2) and serotonin Type 2 (5HT 2A) receptors with binding affinities (Ki values) of 1.6-2.8 nM for D 2 and 0.8-1.2 nM for 5HT 2A receptors. Paliperidone is also active as an antagonist at the α 1 and α 2 adrenergic receptors and H 1 histaminergic receptors, which may explain some of the other effects of the drug. Paliperidone has no affinity for cholinergic muscarinic or β1 and β2-adrenergic receptors. The pharmacological activity of the (+)- and (-)- paliperidone enantiomers is qualitatively and quantitatively similar in vitro.

Schizophrenia:

• Initiation Dosing: Day 1-234 mg and Day 8-156 mg
• Monthly Maintenance Dose: 39-234 mg
• Maximum Monthly Dose: 234 mg

Schizoaffective disorder:

• Initiation Dosing: Day 1-234 mg and Day 8-156 mg
• Monthly Maintenance Dose: 78-234 mg
• Maximum Monthly Dose: 234 mg

Administered 5 weeks after the first injection. The recommended maintenance dose for treatment of schizophrenia is 117 mg. Some patients may benefit from lower or higher maintenance doses within the additional available strengths (39 mg, 78 mg, 156 mg, and 234 mg). Adjust dose based on tolerability and/or efficacy using available strengths. The 39 mg strength was not studied in the long-term schizoaffective disorder study.

Administration

For intramuscular injection only. Each injection must be administered only by a healthcare professional. For deltoid injection, use 1-inch 23G needle for patients weighing less than 90 kg or 1 ½-inch 22G needle for patients weighing 90 kg or more. For gluteal injection, use 1 ½-inch 22G needle regardless of patient weight.

Drugs that may cause orthostatic hypotension: An additive effect may occur when co-administered with Paliperidone Palmitate

Strong CYP3A4/P-glycoprotein (P-gp) inducers: Avoid using a strong inducer of CYP3A4 and/or P-gp (e.g., carbamazepine, rifampin, St John’s Wort) during a dosing interval for Paliperidone Palmitate. If administering a strong inducer is necessary, consider managing the patient using paliperidone extended release tablets

Known hypersensitivity to paliperidone, risperidone, or to any excipients in Paliperidone Palmitate.

The most common adverse reactions (incidence ≥ 5% and occurring at least twice as often as placebo) were injection site reactions, somnolence/sedation, dizziness, akathisia, and extrapyramidal disorder.

Limited data from published literature report the presence of paliperidone in human breast milk. There is no information on the effects on the breastfed infant or the effects on milk production.

Cerebrovascular Adverse Reactions, Including Stroke, in Elderly Patients with Dementia-Related Psychosis: Increased incidence of cerebrovascular adverse reactions (e.g. stroke, transient ischemic attack).

Neuroleptic Malignant Syndrome: Manage with immediate discontinuation of drug and close monitoring.

QT Prolongation: Avoid use with drugs that also increase QT interval and in patients with risk factors for prolonged QT interval.

Tardive Dyskinesia: Discontinue drug if clinically appropriate.

Metabolic Changes: Monitor for hyperglycemia/diabetes mellitus, dyslipidemia and weight gain.

Orthostatic Hypotension and Syncope: Monitor heart rate and blood pressure and warn patients with known cardiovascular or cerebrovascular disease, and risk of dehydration or syncope.

Leukopenia, Neutropenia, and Agranulocytosis: Perform complete blood counts (CBC) in patients with pre-existing low white blood cell count (WBC) or history of leukopenia or neutropenia. Consider discontinuing Paliperidone Palmitate if clinically significant decline in WBC in the absence of other causative factors.

Hyperprolactinemia: Prolactin elevations occur and persist during chronic administration.

Potential for Cognitive and Motor Impairment: Use caution when operating machinery.

Seizures: Use cautiously in patients with a history of seizures or with conditions that lower the seizure threshold.

Atypical neuroleptic drugs

Pediatric Use: Safety and effectiveness of Paliperidone Palmitate in patients <18 years of age have not been established.

Renal Impairment: Not recommended in patients with moderate or severe renal impairment

Hepatic Impairment: Paliperidone has not been studied in patients with hepatic impairment. Based on a study with oral paliperidone, no dose adjustment is required in patients with mild or moderate hepatic impairment.

Store at room temperature; excursions between 15°C and 30°C are permitted. Do not mix with any other product or diluent.