Overview
11 DESCRIPTION Posaconazole is an azole antifungal agent. Posaconazole is available as delayed-release tablet intended for oral administration. Posaconazole is designated chemically as 4-[4-[4-[4-[[(3R,5R)-5-(2,4-difluorophenyl)tetrahydro-5-(1H-1,2,4-triazol-1-ylmethyl)-3-furanyl]methoxy]phenyl]-1-piperazinyl]phenyl]-2-[(1S,2S)-1-ethyl-2-hydroxypropyl]-2,4-dihydro-3H-1,2,4-triazol-3-one with a...
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Posaconazole is an azole antifungal agent [ see Clinical Pharmacology (12.4) ]. 12.2 Pharmacodynamics Exposure Response Relationship Prophylaxis: In clinical studies of neutropenic patients who were receiving cytotoxic chemotherapy for acute myelogenous leukemia (AML) or myelodysplastic syndromes (MDS) or hematopoietic stem cell transplant (HSCT) recipients with Graft versus Host Disease (GVHD), a wide range of plasma exposures to posaconazole was noted following administration of Noxafil ® oral suspension. A pharmacokinetic-pharmacodynamic analysis of patient data revealed an apparent association between average posaconazole concentrations (C avg ) and prophylactic efficacy (Table 17).
Indications
- 1 INDICATIONS AND USAGE Posaconazole is an azole antifungal indicated as follows: Posaconazole is indicated for the prophylaxis of invasive Aspergillus and Candida infections in patients who are at high risk of developing these infections due to being severely immunocompromised, such as hematopoietic stem cell transplant (HSCT) recipients with graft-versus-host disease (GVHD) or those with hematologic malignancies with prolonged neutropenia from chemotherapy as follows: ( 1.
Common Doses
- 300 mg
- 100 mg
Dosage
2 DOSAGE AND ADMINISTRATION Noxafil ® oral suspension is not substitutable with posaconazole delayed-release tablets or Noxafil ® PowderMix for delayed-release oral suspension due to the differences in the dosing of each formulation. Therefore, follow the specific dosage recommendations for each of the formulations. ( 2.1 , 2.2 , 2.3 ) Administer posaconazole delayed-release tablets with or without food. ( 2.1 ) Table 1: Recommended Dosage in Adult Patients Indication Dosage Form, Dose, and Duration of Therapy Prophylaxis of invasive Aspergillus and Candida infections Delayed-Release Tablets:...
Contraindications
- 4 CONTRAINDICATIONS Known hypersensitivity to posaconazole or other azole antifungal agents. ( 4.1 ) Coadministration of posaconazole with the following drugs is contraindicated; posaconazole increases concentrations and toxicities of: Sirolimus ( 4.2 , 5.1 , 7.1 ) CYP3A4 substrates (pimozide, quinidine): can result in QTc interval prolongation and cases of torsades de pointes (TdP) ( 4.3 , 5.2 , 7.2 ) HMG-CoA Reductase Inhibitors Primarily Metabolized through CYP3A4 ( 4.4 , 7.3 ) Ergot alkaloids ( 4.5 , 7.
Side Effects
- 6 ADVERSE REACTIONS The following serious and otherwise important adverse reactions are discussed in detail in another section of the labeling: Hypersensitivity [ see Contraindications (4.1) ] Arrhythmias and QT Prolongation [ see Warnings and Precautions (5.2) ] Hepatic Toxicity [ see Warnings and Precautions (5.5) ] Adult Patients: Common adverse reactions in studies with posaconazole in adults are diarrhea, nausea, fever, vomiting, headache, coughing, and hypokalemia. ( 6.
Interactions
- 7 DRUG INTERACTIONS Posaconazole is primarily metabolized via UDP glucuronosyltransferase and is a substrate of p-glycoprotein (P-gp) efflux. Therefore, inhibitors or inducers of these clearance pathways may affect posaconazole plasma concentrations. Coadministration of drugs that can decrease the plasma concentrations of posaconazole should generally be avoided unless the benefit outweighs the risk. If such drugs are necessary, patients should be monitored closely for breakthrough fungal infections. Posaconazole is also a strong inhibitor of CYP3A4.