Praziquantel

12.1 Mechanism of Action Praziquantel is an anthelmintic drug [see Microbiology (12.4) ] .

1 INDICATIONS AND USAGE Praziquantel tablets are indicated in patients aged 1 year and older for the treatment of the following infections: Schistosomiasis due to all species of schistosoma (for example, Schistosoma mekongi, Schistosoma japonicum, Schistosoma mansoni and Schistosoma hematobium ), and Clonorchiasis and Opisthorchiasis due to the liver flukes, Clonorchis sinensis/Opisthorchis viverrini (approval of this indication was based on studies in which the two species were not differentiated) Praziquantel tablets are an anthelmintic indicated in patients aged one year and older for the treatment of the following infections: Schistosomiasis due to all species of schistosoma (for example , Schistosoma mekongi , Schistosoma japonicum , Schistosoma mansoni and Schistosoma hematobium ), and, Clonorchiasis and Opisthorchiasis due to the liver flukes, Clonorchis sinensis and Opisthorchis viverrini

2 DOSAGE AND ADMINISTRATION Schistosomiasis : 20 mg/kg body weight 3 times a day separated by 4 to 6 hours for 1 day only. ( 2.1 ) Clonorchiasis and Opisthorchiasis : 25 mg/kg 3 times a day separated by 4 to 6 hours for 1 day only. ( 2.1 ) Take with water during meals. Do not chew or keep segments in the mouth. ( 2.2 ) For pediatric patients under 6 years of age, the tablets may be crushed or disintegrated and mixed with semi-solid food or liquid. ( 2.2 ) For additional administration instructions see the full prescribing information. 2.1 Recommended Dosage Schistosomiasis The recommended dosage for the treatment of schistosomiasis is 20 mg/kg bodyweight administered orally three times a day separated by 4 to 6 hours, for 1 day only. Clonorchiasis and Opisthorchiasis The recommended dosage for the treatment of clonorchiasis and opisthorchiasis is 25 mg/kg bodyweight administered orally three times a day separated by 4 to 6 hours for 1 day only. 2.2 Administration Take tablets with water during meals. Do not chew or keep the tablets (or parts of tablets) in the mouth; the bitter taste may cause gagging or vomiting. To prevent choking in pediatric patients under 6 years of age, the tablets may be crushed or disintegrated and mixed with semi-solid food or liquid. Use crushed or disintegrated tablets within 1 hour of mixing. Praziquantel 600 mg tablets have three scores which can be split into four segments at the scores. When broken, each of the four segments contains 150 mg of praziquantel so that the dosage can be adjusted to the patient’s bodyweight. Segments are broken off by pressing the score (notch) with thumbnails. If one-quarter of a tablet is required, this is best achieved by breaking the segment from the outer end.

6 ADVERSE REACTIONS The following serious or otherwise important adverse reactions are discussed elsewhere in the labeling: Clinical Deterioration [see Warnings and Precautions (5.1) ] Central Nervous System (CNS) Effects [see Warnings and Precautions (5.2) ] Potential Lack of Efficacy During the Acute Phase of Schistosomiasis [see Warnings and Precautions (5.3) ] Cardiac Arrhythmias [see Warnings and Precautions (5.4) ] Hepatic Impairment in Hepatosplenic Schistosomiasis Patients [see Warnings and Precautions (5.5) ] Concomitant Administration with Strong Cytochrome P450 Inducers [see Warnings and Precautions (5.6) ] The following adverse reactions associated with the use of praziquantel were identified in clinical studies, published literature or postmarketing reports. Because some of these reactions were 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 adverse reactions were observed in both adults and pediatric patients: General disorders and administration site conditions: malaise, pyrexia Nervous system disorders: headache, dizziness Gastrointestinal disorders: abdominal discomfort, nausea Skin and subcutaneous tissue disorders: urticaria Such adverse reactions may be more frequent and/or serious in patients with a heavy worm burden. Additional adverse reactions reported from worldwide post marketing experience and from publications with praziquantel and various formulations of praziquantel include: Blood and lymphatic system disorders: eosinophilia Cardiac disorders: arrhythmia (including bradycardia, ectopic rhythms, ventricular fibrillation, AV blocks) Ear and labyrinth disorders: vertigo, tinnitus Eye disorders: visual disturbance Gastrointestinal disorders: abdominal pain, bloody diarrhea, vomiting General disorders and administration site conditions: polyserositis, asthenia, fatigue, gait disturbance Hepatobiliary disorders: hepatitis Immune system disorders: allergic reaction, generalized hypersensitivity, anaphylactic reaction Metabolism and nutrition disorders: anorexia Musculoskeletal and connective tissue disorders: myalgia Nervous system disorders: convulsion, somnolence, intention tremor Respiratory, thoracic and mediastinal disorders: pneumonitis, dyspnea, wheezing Skin and subcutaneous tissue disorders: pruritus, rash, Stevens-Johnson syndrome Pediatric patients 1 to 17 years of age treated with praziquantel tablets and various formulations of praziquantel experienced similar adverse reactions as those observed in adult patients. The adverse reactions reported were malaise, headache, dizziness, abdominal discomfort (with or without nausea), pyrexia and urticaria. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Endo at 1-800-828-9393 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

7 DRUG INTERACTIONS Moderate CYP 3A Inducers : Avoid concomitant administration of moderate CYP 3A inducers, for example, efavirenz ( 5.6 , 7.1 ) 7.1 CYP 3A Inducers Strong and Moderate CYP 3A Inducers Concomitant administration of praziquantel with Strong and Moderate CYP 3A inducers decrease praziquantel AUC and C max [see Clinical Pharmacology (12.3) ] which may reduce the efficacy of praziquantel. Concomitant administration of a Strong CYP 3A inducer, such as rifampin, with praziquantel is contraindicated [see Contraindications (4) ]. Concomitant administration of a Moderate CYP 3A inducer, such as efavirenz, should be avoided unless the benefit outweighs the risks [see Warnings and Precautions (5.6) and Clinical Pharmacology (12.3) .] 7.2 CYP450 Inhibitors Concomitant administration of drugs that decrease the activity of drug metabolizing liver enzymes (CYP450 inhibitors), for example, cimetidine, ketoconazole, itraconazole, erythromycin, and ritonavir may increase plasma concentrations of praziquantel. In addition, grapefruit juice was also reported to produce a 1.6-fold increase in the C max and a 1.9-fold increase in the AUC of praziquantel. The effect of this exposure increase on the safety of praziquantel has not been systematically evaluated [see Dosage and Administration (2.2) ].