POSACONAZOLE Drug Interactions: What You Need to Know

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. Therefore, plasma concentrations of drugs predominantly metabolized by CYP3A4 may be increased by posaconazole [see Clinical Pharmacology ( 12.3 )]. The following information was derived from data with Noxafil ® oral suspension or early tablet formulation unless otherwise noted. All drug interactions with Noxafil ® oral suspension, except for those that affect the absorption of posaconazole (via gastric pH and motility), are considered relevant to posaconazole delayed-release tablet, as well [see Drug Interactions ( 7.9 ) and ( 7.13 )].

Interaction Drug Interaction

Rifabutin, phenytoin, efavirenz, cimetidine Avoid coadministration unless the benefit outweighs the risks ( 7.6 , 7.7 , 7.8 , 7.9 ) Other drugs metabolized by CYP3A4 Consider dosage adjustment and monitor for adverse effects and toxicity ( 7.1 , 7.10 , 7.11 )

Digoxin

Monitor digoxin plasma concentrations ( 7.12 )

Fosamprenavir

Monitor for breakthrough fungal infections ( 7.6 , 7.13 )

7.1 Immunosuppressants Metabolized by CYP3A4 Sirolimus : Concomitant administration of posaconazole with sirolimus increases the sirolimus blood concentrations by approximately 9-fold and can result in sirolimus toxicity. Therefore, posaconazole is contraindicated with sirolimus <span class="opacity-50 text-xs">[see Contraindications ( 4.2 ) and Clinical Pharmacology ( 12.3 )]</span>. Tacrolimus : Posaconazole has been shown to significantly increase the C max and AUC of tacrolimus. At initiation of posaconazole treatment, reduce the tacrolimus dose to approximately one-third of the original dose. Frequent monitoring of tacrolimus whole blood trough concentrations should be performed during and at discontinuation of posaconazole treatment and the tacrolimus dose adjusted accordingly <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5.1 ) and Clinical Pharmacology ( 12.3 )]</span>. Cyclosporine : Posaconazole has been shown to increase cyclosporine whole blood concentrations in heart transplant patients upon initiation of posaconazole treatment. It is recommended to reduce cyclosporine dose to approximately three-fourths of the original dose upon initiation of posaconazole treatment. Frequent monitoring of cyclosporine whole blood trough concentrations should be performed during and at discontinuation of posaconazole treatment and the cyclosporine dose adjusted accordingly <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5.1 ) and Clinical Pharmacology ( 12.3 )]</span>.

7.2 CYP3A4 Substrates Concomitant administration of posaconazole with CYP3A4 substrates such as pimozide and quinidine may result in increased plasma concentrations of these drugs, leading to QTc prolongation and cases of torsades de pointes. Therefore, posaconazole is contraindicated with these drugs <span class="opacity-50 text-xs">[see Contraindications ( 4.3 ) and Warnings and Precautions ( 5.2 )]</span>.

7.3 HMG-CoA Reductase Inhibitors (Statins)

Primarily Metabolized

Through CYP3A4 Concomitant administration of posaconazole with simvastatin increases the simvastatin plasma concentrations by approximately 10-fold. Therefore, posaconazole is contraindicated with HMG-CoA reductase inhibitors primarily metabolized through CYP3A4 [see Contraindications ( 4.4 ) and Clinical Pharmacology ( 12.3 )].

7.4 Ergot Alkaloids Most of the ergot alkaloids are substrates of CYP3A4. Posaconazole may increase the plasma concentrations of ergot alkaloids (ergotamine and dihydroergotamine) which may lead to ergotism. Therefore, posaconazole is contraindicated with ergot alkaloids <span class="opacity-50 text-xs">[see Contraindications ( 4.5 )]</span>.

7.5 Benzodiazepines Metabolized by CYP3A4 Concomitant administration of posaconazole with midazolam increases the midazolam plasma concentrations by approximately 5-fold. Increased plasma midazolam concentrations could potentiate and prolong hypnotic and sedative effects. Concomitant use of posaconazole and other benzodiazepines metabolized by CYP3A4 (e.g., alprazolam, triazolam) could result in increased plasma concentrations of these benzodiazepines. Patients must be monitored closely for adverse effects associated with high plasma concentrations of benzodiazepines metabolized by CYP3A4 and benzodiazepine receptor antagonists must be available to reverse these effects <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5.7 ) and Clinical Pharmacology ( 12.3 )]</span>.

7.6 Anti-HIV Drugs Efavirenz : Efavirenz induces UDP-glucuronidase and significantly decreases posaconazole plasma concentrations <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span> . It is recommended to avoid concomitant use of efavirenz with posaconazole unless the benefit outweighs the risks. Ritonavir and Atazanavir : Ritonavir and atazanavir are metabolized by CYP3A4 and posaconazole increases plasma concentrations of these drugs <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span>. Frequent monitoring of adverse effects and toxicity of ritonavir and atazanavir should be performed during coadministration with posaconazole. Fosamprenavir : Combining fosamprenavir with posaconazole may lead to decreased posaconazole plasma concentrations. If concomitant administration is required, close monitoring for breakthrough fungal infections is recommended <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span> .

7.7 Rifabutin Rifabutin induces UDP-glucuronidase and decreases posaconazole plasma concentrations. Rifabutin is also metabolized by CYP3A4. Therefore, coadministration of rifabutin with posaconazole increases rifabutin plasma concentrations <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span> . Concomitant use of posaconazole and rifabutin should be avoided unless the benefit to the patient outweighs the risk. However, if concomitant administration is required, close monitoring for breakthrough fungal infections as well as frequent monitoring of full blood counts and adverse reactions due to increased rifabutin plasma concentrations (e.g., uveitis, leukopenia) are recommended.

7.8 Phenytoin Phenytoin induces UDP-glucuronidase and decreases posaconazole plasma concentrations. Phenytoin is also metabolized by CYP3A4. Therefore, coadministration of phenytoin with posaconazole increases phenytoin plasma concentrations <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span> . Concomitant use of posaconazole and phenytoin should be avoided unless the benefit to the patient outweighs the risk. However, if concomitant administration is required, close monitoring for breakthrough fungal infections is recommended and frequent monitoring of phenytoin concentrations should be performed while coadministered with posaconazole and dose reduction of phenytoin should be considered.

7.9 Gastric Acid Suppressors/Neutralizers No clinically relevant effects on the pharmacokinetics of posaconazole were observed when posaconazole delayed-release tablets are concomitantly used with antacids, H 2 -receptor antagonists and proton pump inhibitors <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span>. No dosage adjustment of posaconazole delayed-release tablets is required when concomitantly used with antacids, H 2 -receptor antagonists and proton pump inhibitors.

7.10 Vinca Alkaloids Most of the vinca alkaloids (e.g., vincristine and vinblastine) are substrates of CYP3A4. Concomitant administration of azole antifungals, including posaconazole, with vincristine has been associated with serious adverse reactions <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5.8 )]</span>. Posaconazole may increase the plasma concentrations of vinca alkaloids which may lead to neurotoxicity and other serious adverse reactions. Therefore, reserve azole antifungals, including posaconazole, for patients receiving a vinca alkaloid, including vincristine, who have no alternative antifungal treatment options.

7.11 Calcium Channel Blockers Metabolized by CYP3A4 Posaconazole may increase the plasma concentrations of calcium channel blockers metabolized by CYP3A4 (e.g., verapamil, diltiazem, nifedipine, nicardipine, felodipine). Frequent monitoring for adverse reactions and toxicity related to calcium channel blockers is recommended during coadministration. Dose reduction of calcium channel blockers may be needed.

7.12 Digoxin Increased plasma concentrations of digoxin have been reported in patients receiving digoxin and posaconazole. Therefore, monitoring of digoxin plasma concentrations is recommended during coadministration.

7.13 Gastrointestinal Motility Agents Concomitant administration of metoclopramide with posaconazole delayed-release tablets did not affect the pharmacokinetics of posaconazole <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span> . No dosage adjustment of posaconazole delayed-release tablets is required when given concomitantly with metoclopramide.

7.14 Glipizide Although no dosage adjustment of glipizide is required, it is recommended to monitor glucose concentrations when posaconazole and glipizide are concomitantly used.

7.16 Venetoclax Concomitant use of venetoclax (a CYP3A4 substrate) with posaconazole increases venetoclax C max and AUC 0-INF , which may increase venetoclax toxicities <span class="opacity-50 text-xs">[see Contraindications (4.6 ), Warnings and Precautions ( 5.11 )]</span>. Refer to the venetoclax prescribing information for more information on the dosing instructions and the extent of increase in venetoclax exposure.

7.1 Immunosuppressants Metabolized by CYP3A4 Sirolimus : Concomitant administration of posaconazole with sirolimus increases the sirolimus blood concentrations by approximately 9-fold and can result in sirolimus toxicity. Therefore, posaconazole is contraindicated with sirolimus <span class="opacity-50 text-xs">[see Contraindications ( 4.2 ) and Clinical Pharmacology ( 12.3 )]</span>. Tacrolimus : Posaconazole has been shown to significantly increase the C max and AUC of tacrolimus. At initiation of posaconazole treatment, reduce the tacrolimus dose to approximately one-third of the original dose. Frequent monitoring of tacrolimus whole blood trough concentrations should be performed during and at discontinuation of posaconazole treatment and the tacrolimus dose adjusted accordingly <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5.1 ) and Clinical Pharmacology ( 12.3 )]</span>. Cyclosporine : Posaconazole has been shown to increase cyclosporine whole blood concentrations in heart transplant patients upon initiation of posaconazole treatment. It is recommended to reduce cyclosporine dose to approximately three-fourths of the original dose upon initiation of posaconazole treatment. Frequent monitoring of cyclosporine whole blood trough concentrations should be performed during and at discontinuation of posaconazole treatment and the cyclosporine dose adjusted accordingly <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5.1 ) and Clinical Pharmacology ( 12.3 )]</span>.

7.2 CYP3A4 Substrates Concomitant administration of posaconazole with CYP3A4 substrates such as pimozide and quinidine may result in increased plasma concentrations of these drugs, leading to QTc prolongation and cases of torsades de pointes. Therefore, posaconazole is contraindicated with these drugs <span class="opacity-50 text-xs">[see Contraindications ( 4.3 ) and Warnings and Precautions ( 5.2 )]</span>.

7.3 HMG-CoA Reductase Inhibitors (Statins)

Primarily Metabolized

Through CYP3A4 Concomitant administration of posaconazole with simvastatin increases the simvastatin plasma concentrations by approximately 10-fold. Therefore, posaconazole is contraindicated with HMG-CoA reductase inhibitors primarily metabolized through CYP3A4 [see Contraindications ( 4.4 ) and Clinical Pharmacology ( 12.3 )].

7.4 Ergot Alkaloids Most of the ergot alkaloids are substrates of CYP3A4. Posaconazole may increase the plasma concentrations of ergot alkaloids (ergotamine and dihydroergotamine) which may lead to ergotism. Therefore, posaconazole is contraindicated with ergot alkaloids <span class="opacity-50 text-xs">[see Contraindications ( 4.5 )]</span>.

7.5 Benzodiazepines Metabolized by CYP3A4 Concomitant administration of posaconazole with midazolam increases the midazolam plasma concentrations by approximately 5-fold. Increased plasma midazolam concentrations could potentiate and prolong hypnotic and sedative effects. Concomitant use of posaconazole and other benzodiazepines metabolized by CYP3A4 (e.g., alprazolam, triazolam) could result in increased plasma concentrations of these benzodiazepines. Patients must be monitored closely for adverse effects associated with high plasma concentrations of benzodiazepines metabolized by CYP3A4 and benzodiazepine receptor antagonists must be available to reverse these effects <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5.7 ) and Clinical Pharmacology ( 12.3 )]</span>.

7.6 Anti-HIV Drugs Efavirenz : Efavirenz induces UDP-glucuronidase and significantly decreases posaconazole plasma concentrations <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span> . It is recommended to avoid concomitant use of efavirenz with posaconazole unless the benefit outweighs the risks. Ritonavir and Atazanavir : Ritonavir and atazanavir are metabolized by CYP3A4 and posaconazole increases plasma concentrations of these drugs <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span>. Frequent monitoring of adverse effects and toxicity of ritonavir and atazanavir should be performed during coadministration with posaconazole. Fosamprenavir : Combining fosamprenavir with posaconazole may lead to decreased posaconazole plasma concentrations. If concomitant administration is required, close monitoring for breakthrough fungal infections is recommended <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span> .

7.7 Rifabutin Rifabutin induces UDP-glucuronidase and decreases posaconazole plasma concentrations. Rifabutin is also metabolized by CYP3A4. Therefore, coadministration of rifabutin with posaconazole increases rifabutin plasma concentrations <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span> . Concomitant use of posaconazole and rifabutin should be avoided unless the benefit to the patient outweighs the risk. However, if concomitant administration is required, close monitoring for breakthrough fungal infections as well as frequent monitoring of full blood counts and adverse reactions due to increased rifabutin plasma concentrations (e.g., uveitis, leukopenia) are recommended.

7.8 Phenytoin Phenytoin induces UDP-glucuronidase and decreases posaconazole plasma concentrations. Phenytoin is also metabolized by CYP3A4. Therefore, coadministration of phenytoin with posaconazole increases phenytoin plasma concentrations <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span> . Concomitant use of posaconazole and phenytoin should be avoided unless the benefit to the patient outweighs the risk. However, if concomitant administration is required, close monitoring for breakthrough fungal infections is recommended and frequent monitoring of phenytoin concentrations should be performed while coadministered with posaconazole and dose reduction of phenytoin should be considered.

7.9 Gastric Acid Suppressors/Neutralizers No clinically relevant effects on the pharmacokinetics of posaconazole were observed when posaconazole delayed-release tablets are concomitantly used with antacids, H 2 -receptor antagonists and proton pump inhibitors <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span>. No dosage adjustment of posaconazole delayed-release tablets is required when concomitantly used with antacids, H 2 -receptor antagonists and proton pump inhibitors.

7.10 Vinca Alkaloids Most of the vinca alkaloids (e.g., vincristine and vinblastine) are substrates of CYP3A4. Concomitant administration of azole antifungals, including posaconazole, with vincristine has been associated with serious adverse reactions <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5.8 )]</span>. Posaconazole may increase the plasma concentrations of vinca alkaloids which may lead to neurotoxicity and other serious adverse reactions. Therefore, reserve azole antifungals, including posaconazole, for patients receiving a vinca alkaloid, including vincristine, who have no alternative antifungal treatment options.

7.11 Calcium Channel Blockers Metabolized by CYP3A4 Posaconazole may increase the plasma concentrations of calcium channel blockers metabolized by CYP3A4 (e.g., verapamil, diltiazem, nifedipine, nicardipine, felodipine). Frequent monitoring for adverse reactions and toxicity related to calcium channel blockers is recommended during coadministration. Dose reduction of calcium channel blockers may be needed.

7.12 Digoxin Increased plasma concentrations of digoxin have been reported in patients receiving digoxin and posaconazole. Therefore, monitoring of digoxin plasma concentrations is recommended during coadministration.

7.13 Gastrointestinal Motility Agents Concomitant administration of metoclopramide with posaconazole delayed-release tablets did not affect the pharmacokinetics of posaconazole <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span> . No dosage adjustment of posaconazole delayed-release tablets is required when given concomitantly with metoclopramide.

7.14 Glipizide Although no dosage adjustment of glipizide is required, it is recommended to monitor glucose concentrations when posaconazole and glipizide are concomitantly used.

7.16 Venetoclax Concomitant use of venetoclax (a CYP3A4 substrate) with posaconazole increases venetoclax C max and AUC 0-INF , which may increase venetoclax toxicities <span class="opacity-50 text-xs">[see Contraindications (4.6 ), Warnings and Precautions ( 5.11 )]</span>. Refer to the venetoclax prescribing information for more information on the dosing instructions and the extent of increase in venetoclax exposure.

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 , 7.4 )
• Venetoclax: in patients with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL) at initiation and during the ramp up phase ( 4.6 , 5.10 , 7.16 )

4.1 Hypersensitivity Posaconazole is contraindicated in persons with known hypersensitivity to posaconazole or other azole antifungal agents.

4.2 Use with Sirolimus Posaconazole is contraindicated with sirolimus. Concomitant administration of posaconazole with sirolimus increases the sirolimus blood concentrations by approximately 9-fold and can result in sirolimus toxicity <span class="opacity-50 text-xs">[see Drug Interactions ( 7.1 ) and Clinical Pharmacology ( 12.3 )]</span> .

4.3 QT Prolongation with Concomitant Use with CYP3A4 Substrates Posaconazole is contraindicated with CYP3A4 substrates that prolong the QT interval. Concomitant administration of posaconazole with the CYP3A4 substrates, pimozide and quinidine may result in increased plasma concentrations of these drugs, leading to QTc prolongation and cases of torsades de pointes <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5.2 ) and Drug Interactions ( 7.2 )]</span>.

4.4 HMG-CoA Reductase Inhibitors Primarily Metabolized Through CYP3A4 Coadministration with the HMG-CoA reductase inhibitors that are primarily metabolized through CYP3A4 (e.g., atorvastatin, lovastatin, and simvastatin) is contraindicated since increased plasma concentration of these drugs can lead to rhabdomyolysis <span class="opacity-50 text-xs">[see Drug Interactions ( 7.3 ) and Clinical Pharmacology ( 12.3 )]</span> .

4.5 Use with Ergot Alkaloids Posaconazole may increase the plasma concentrations of ergot alkaloids (ergotamine and dihydroergotamine) which may lead to ergotism <span class="opacity-50 text-xs">[see Drug Interactions ( 7.4 )]</span>.

4.6 Use with Venetoclax Coadministration of posaconazole with venetoclax at initiation and during the ramp-up phase is contraindicated in patients with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL) due to the potential for increased risk of tumor lysis syndrome <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5.10 ) and Drug Interactions ( 7.16 )]</span>.

4.1 Hypersensitivity Posaconazole is contraindicated in persons with known hypersensitivity to posaconazole or other azole antifungal agents.

4.2 Use with Sirolimus Posaconazole is contraindicated with sirolimus. Concomitant administration of posaconazole with sirolimus increases the sirolimus blood concentrations by approximately 9-fold and can result in sirolimus toxicity <span class="opacity-50 text-xs">[see Drug Interactions ( 7.1 ) and Clinical Pharmacology ( 12.3 )]</span> .

4.3 QT Prolongation with Concomitant Use with CYP3A4 Substrates Posaconazole is contraindicated with CYP3A4 substrates that prolong the QT interval. Concomitant administration of posaconazole with the CYP3A4 substrates, pimozide and quinidine may result in increased plasma concentrations of these drugs, leading to QTc prolongation and cases of torsades de pointes <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5.2 ) and Drug Interactions ( 7.2 )]</span>.

4.4 HMG-CoA Reductase Inhibitors Primarily Metabolized Through CYP3A4 Coadministration with the HMG-CoA reductase inhibitors that are primarily metabolized through CYP3A4 (e.g., atorvastatin, lovastatin, and simvastatin) is contraindicated since increased plasma concentration of these drugs can lead to rhabdomyolysis <span class="opacity-50 text-xs">[see Drug Interactions ( 7.3 ) and Clinical Pharmacology ( 12.3 )]</span> .

4.5 Use with Ergot Alkaloids Posaconazole may increase the plasma concentrations of ergot alkaloids (ergotamine and dihydroergotamine) which may lead to ergotism <span class="opacity-50 text-xs">[see Drug Interactions ( 7.4 )]</span>.

4.6 Use with Venetoclax Coadministration of posaconazole with venetoclax at initiation and during the ramp-up phase is contraindicated in patients with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL) due to the potential for increased risk of tumor lysis syndrome <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5.10 ) and Drug Interactions ( 7.16 )]</span>.

AND PRECAUTIONS Calcineurin Inhibitor Toxicity : Posaconazole increases concentrations of cyclosporine or tacrolimus; reduce dose of cyclosporine and tacrolimus and monitor concentrations frequently. ( 5.1 ) Arrhythmias and QTc Prolongation : Posaconazole has been shown to prolong the QTc interval and cause cases of TdP. Administer with caution to patients with potentially proarrhythmic conditions. Do not administer with drugs known to prolong QTc interval and metabolized through CYP3A4. ( 5.2 )

Electrolyte

Disturbances : Monitor and correct, especially those involving potassium (K + ), magnesium (Mg ++ ), and calcium (Ca ++ ), before and during posaconazole therapy. (5.3) Pseudoaldosteronism : Manifested by the onset or worsening of hypertension, and abnormal laboratory findings. Monitor blood pressure and potassium levels, and manage as necessary. (5.4)

Hepatic

Toxicity : Elevations in liver tests may occur. Discontinuation should be considered in patients who develop abnormal liver tests or monitor liver tests during treatment. ( 5.5 )

Concomitant

Use with Midazolam : Posaconazole can prolong hypnotic/sedative effects. Monitor patients and benzodiazepine receptor antagonists should be available. ( 5.7 , 7.5 )

Vincristine

Toxicity : Concomitant administration of azole antifungals, including posaconazole, with vincristine has been associated with neurotoxicity and other serious adverse reactions; reserve azole antifungals, including posaconazole, for patients receiving a vinca alkaloid, including vincristine, who have no alternative antifungal treatment options. ( 5.8 , 7.10 )

Breakthrough Fungal

Infections : Monitor patients with severe diarrhea or vomiting when receiving posaconazole delayed-release tablets. ( 5.10 )

Venetoclax

Toxicity: Concomitant administration of posaconazole with venetoclax may increase venetoclax toxicities, including the risk of tumor lysis syndrome, neutropenia, and serious infections; monitor for toxicity and reduce venetoclax dose. ( 4.6 , 5.11 , 7.16)

5.1 Calcineurin-Inhibitor Toxicity Concomitant administration of posaconazole with cyclosporine or tacrolimus increases the whole blood trough concentrations of these calcineurin-inhibitors <span class="opacity-50 text-xs">[see Drug Interactions ( 7.1 ) and Clinical Pharmacology ( 12.3 )]</span> . Nephrotoxicity and leukoencephalopathy (including deaths) have been reported in clinical efficacy studies in patients with elevated cyclosporine or tacrolimus concentrations. Frequent monitoring of tacrolimus or cyclosporine whole blood trough concentrations should be performed during and at discontinuation of posaconazole treatment and the tacrolimus or cyclosporine dose adjusted accordingly.

5.2 Arrhythmias and QT Prolongation Some azoles, including posaconazole, have been associated with prolongation of the QT interval on the electrocardiogram. In addition, cases of torsades de pointes have been reported in patients taking posaconazole. Results from a multiple time-matched ECG analysis in healthy volunteers did not show any increase in the mean of the QTc interval. Multiple, time-matched ECGs collected over a 12-hour period were recorded at baseline and steady-state from 173 healthy male and female volunteers (18 -85 years of age) administered Noxafil ® oral suspension 400 mg twice daily with a high-fat meal. In this pooled analysis, the mean QTc (Fridericia) interval change from baseline was –5 msec following administration of the recommended clinical dose. A decrease in the QTc(F) interval (–3 msec) was also observed in a small number of subjects (n=16) administered placebo. The placebo-adjusted mean maximum QTc(F) interval change from baseline was &lt;0 msec (–8 msec). No healthy subject administered posaconazole had a QTc(F) interval ≥500 msec or an increase ≥60 msec in their QTc(F) interval from baseline. Posaconazole should be administered with caution to patients with potentially proarrhythmic conditions. Do not administer with drugs that are known to prolong the QTc interval and are metabolized through CYP3A4 <span class="opacity-50 text-xs">[see Contraindications ( 4.3 ) and Drug Interactions ( 7.2 )]</span> .

5.3 Electrolyte Disturbances Electrolyte disturbances, especially those involving potassium, magnesium or calcium levels, should be monitored and corrected as necessary before and during posaconazole therapy.

5.4 Pseudoaldosteronism Pseudoaldosteronism, manifested by the onset of hypertension or worsening of hypertension, and abnormal laboratory findings (hypokalemia, low serum renin and aldosterone, and elevated 11-deoxycortisol), has been reported with posaconazole use in the postmarket setting. Monitor blood pressure and potassium levels and manage as necessary. Management of pseudoaldosteronism may include discontinuation of posaconazole delayed-release tablets, substitution with an appropriate antifungal drug that is not associated with pseudoaldosteronism, or use of aldosterone receptor antagonists.

5.5 Hepatic Toxicity Hepatic reactions (e.g., mild to moderate elevations in alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase, total bilirubin, and/or clinical hepatitis) have been reported in clinical trials. The elevations in liver tests were generally reversible on discontinuation of therapy, and in some instances these tests normalized without drug interruption. Cases of more severe hepatic reactions including cholestasis or hepatic failure including deaths have been reported in patients with serious underlying medical conditions (e.g., hematologic malignancy) during treatment with posaconazole. These severe hepatic reactions were seen primarily in subjects receiving the Noxafil ® oral suspension 800 mg daily (400 mg twice daily or 200 mg four times a day) in clinical trials. Liver tests should be evaluated at the start of and during the course of posaconazole therapy. Patients who develop abnormal liver tests during posaconazole therapy should be monitored for the development of more severe hepatic injury. Patient management should include laboratory evaluation of hepatic function (particularly liver tests and bilirubin). Discontinuation of posaconazole must be considered if clinical signs and symptoms consistent with liver disease develop that may be attributable to posaconazole.

5.6 Renal Impairment Due to the variability in exposure with posaconazole delayed-release tablets, Noxafil ® oral suspension, and Noxafil ® PowderMix for delayed-release oral suspension, patients with severe renal impairment should be monitored closely for breakthrough fungal infections <span class="opacity-50 text-xs">[see Dosage and Administration ( 2.9 ) and Use in Specific Populations ( 8.6 )]</span>.

5.7 Midazolam Toxicity Concomitant administration of posaconazole with midazolam increases the midazolam plasma concentrations by approximately 5-fold. Increased plasma midazolam concentrations could potentiate and prolong hypnotic and sedative effects. Patients must be monitored closely for adverse effects associated with high plasma concentrations of midazolam and benzodiazepine receptor antagonists must be available to reverse these effects <span class="opacity-50 text-xs">[see Drug Interact ions ( 7.5 ) and Clinical Pharmacology ( 12.3 )]</span>.

5.8 Vincristine Toxicity Concomitant administration of azole antifungals, including posaconazole, with vincristine has been associated with neurotoxicity and other serious adverse reactions, including seizures, peripheral neuropathy, syndrome of inappropriate antidiuretic hormone secretion, and paralytic ileus. Reserve azole antifungals, including posaconazole, for patients receiving a vinca alkaloid, including vincristine, who have no alternative antifungal treatment options <span class="opacity-50 text-xs">[see Drug Interactions ( 7.10 )]</span>.

5.10 Breakthrough Fungal Infections Patients who have severe diarrhea or vomiting should be monitored closely for breakthrough fungal infections when receiving posaconazole delayed-release tablets.

5.11 Venetoclax Toxicity Concomitant administration of posaconazole, a strong CYP3A4 inhibitor, with venetoclax may increase venetoclax toxicities, including the risk of tumor lysis syndrome (TLS), neutropenia, and serious infections. In patients with CLL/SLL, administration of posaconazole during initiation and the ramp-up phase of venetoclax is contraindicated <span class="opacity-50 text-xs">[see Contraindications ( 4.6 )]</span>. Refer to the venetoclax labeling for safety monitoring and dose reduction in the steady daily dosing phase in CLL/SLL patients. For patients with acute myeloid leukemia (AML), dose reduction and safety monitoring are recommended across all dosing phases when coadministering posaconazole with venetoclax <span class="opacity-50 text-xs">[see Drug Interactions ( 7.16 )]</span> . Refer to the venetoclax prescribing information for dosing instructions.

5.1 Calcineurin-Inhibitor Toxicity Concomitant administration of posaconazole with cyclosporine or tacrolimus increases the whole blood trough concentrations of these calcineurin-inhibitors <span class="opacity-50 text-xs">[see Drug Interactions ( 7.1 ) and Clinical Pharmacology ( 12.3 )]</span> . Nephrotoxicity and leukoencephalopathy (including deaths) have been reported in clinical efficacy studies in patients with elevated cyclosporine or tacrolimus concentrations. Frequent monitoring of tacrolimus or cyclosporine whole blood trough concentrations should be performed during and at discontinuation of posaconazole treatment and the tacrolimus or cyclosporine dose adjusted accordingly.

5.2 Arrhythmias and QT Prolongation Some azoles, including posaconazole, have been associated with prolongation of the QT interval on the electrocardiogram. In addition, cases of torsades de pointes have been reported in patients taking posaconazole. Results from a multiple time-matched ECG analysis in healthy volunteers did not show any increase in the mean of the QTc interval. Multiple, time-matched ECGs collected over a 12-hour period were recorded at baseline and steady-state from 173 healthy male and female volunteers (18 -85 years of age) administered Noxafil ® oral suspension 400 mg twice daily with a high-fat meal. In this pooled analysis, the mean QTc (Fridericia) interval change from baseline was –5 msec following administration of the recommended clinical dose. A decrease in the QTc(F) interval (–3 msec) was also observed in a small number of subjects (n=16) administered placebo. The placebo-adjusted mean maximum QTc(F) interval change from baseline was &lt;0 msec (–8 msec). No healthy subject administered posaconazole had a QTc(F) interval ≥500 msec or an increase ≥60 msec in their QTc(F) interval from baseline. Posaconazole should be administered with caution to patients with potentially proarrhythmic conditions. Do not administer with drugs that are known to prolong the QTc interval and are metabolized through CYP3A4 <span class="opacity-50 text-xs">[see Contraindications ( 4.3 ) and Drug Interactions ( 7.2 )]</span> .

5.3 Electrolyte Disturbances Electrolyte disturbances, especially those involving potassium, magnesium or calcium levels, should be monitored and corrected as necessary before and during posaconazole therapy.

5.4 Pseudoaldosteronism Pseudoaldosteronism, manifested by the onset of hypertension or worsening of hypertension, and abnormal laboratory findings (hypokalemia, low serum renin and aldosterone, and elevated 11-deoxycortisol), has been reported with posaconazole use in the postmarket setting. Monitor blood pressure and potassium levels and manage as necessary. Management of pseudoaldosteronism may include discontinuation of posaconazole delayed-release tablets, substitution with an appropriate antifungal drug that is not associated with pseudoaldosteronism, or use of aldosterone receptor antagonists.

5.5 Hepatic Toxicity Hepatic reactions (e.g., mild to moderate elevations in alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase, total bilirubin, and/or clinical hepatitis) have been reported in clinical trials. The elevations in liver tests were generally reversible on discontinuation of therapy, and in some instances these tests normalized without drug interruption. Cases of more severe hepatic reactions including cholestasis or hepatic failure including deaths have been reported in patients with serious underlying medical conditions (e.g., hematologic malignancy) during treatment with posaconazole. These severe hepatic reactions were seen primarily in subjects receiving the Noxafil ® oral suspension 800 mg daily (400 mg twice daily or 200 mg four times a day) in clinical trials. Liver tests should be evaluated at the start of and during the course of posaconazole therapy. Patients who develop abnormal liver tests during posaconazole therapy should be monitored for the development of more severe hepatic injury. Patient management should include laboratory evaluation of hepatic function (particularly liver tests and bilirubin). Discontinuation of posaconazole must be considered if clinical signs and symptoms consistent with liver disease develop that may be attributable to posaconazole.

5.6 Renal Impairment Due to the variability in exposure with posaconazole delayed-release tablets, Noxafil ® oral suspension, and Noxafil ® PowderMix for delayed-release oral suspension, patients with severe renal impairment should be monitored closely for breakthrough fungal infections <span class="opacity-50 text-xs">[see Dosage and Administration ( 2.9 ) and Use in Specific Populations ( 8.6 )]</span>.

5.7 Midazolam Toxicity Concomitant administration of posaconazole with midazolam increases the midazolam plasma concentrations by approximately 5-fold. Increased plasma midazolam concentrations could potentiate and prolong hypnotic and sedative effects. Patients must be monitored closely for adverse effects associated with high plasma concentrations of midazolam and benzodiazepine receptor antagonists must be available to reverse these effects <span class="opacity-50 text-xs">[see Drug Interact ions ( 7.5 ) and Clinical Pharmacology ( 12.3 )]</span>.

5.8 Vincristine Toxicity Concomitant administration of azole antifungals, including posaconazole, with vincristine has been associated with neurotoxicity and other serious adverse reactions, including seizures, peripheral neuropathy, syndrome of inappropriate antidiuretic hormone secretion, and paralytic ileus. Reserve azole antifungals, including posaconazole, for patients receiving a vinca alkaloid, including vincristine, who have no alternative antifungal treatment options <span class="opacity-50 text-xs">[see Drug Interactions ( 7.10 )]</span>.

5.10 Breakthrough Fungal Infections Patients who have severe diarrhea or vomiting should be monitored closely for breakthrough fungal infections when receiving posaconazole delayed-release tablets.

5.11 Venetoclax Toxicity Concomitant administration of posaconazole, a strong CYP3A4 inhibitor, with venetoclax may increase venetoclax toxicities, including the risk of tumor lysis syndrome (TLS), neutropenia, and serious infections. In patients with CLL/SLL, administration of posaconazole during initiation and the ramp-up phase of venetoclax is contraindicated <span class="opacity-50 text-xs">[see Contraindications ( 4.6 )]</span>. Refer to the venetoclax labeling for safety monitoring and dose reduction in the steady daily dosing phase in CLL/SLL patients. For patients with acute myeloid leukemia (AML), dose reduction and safety monitoring are recommended across all dosing phases when coadministering posaconazole with venetoclax <span class="opacity-50 text-xs">[see Drug Interactions ( 7.16 )]</span> . Refer to the venetoclax prescribing information for dosing instructions.