Saquinavir

CYP3A4 inhibitor that can increase systemic budesonide concentrations. Avoid use.

Strong CYP3A4 inhibitor causing significant increases in colchicine plasma levels.

Anticipated significant increase in saxagliptin plasma concentrations. Do not coadminister with dapagliflozin and saxagliptin.

Strong CYP3A4 inhibitor; concomitant use is contraindicated due to increased risk of hypotension and syncope.

Strong CYP3A4 inhibitor may increase systemic corticosteroid effects of fluticasone propionate.

Strong CYP3A4 inhibitor may increase systemic corticosteroid and cardiovascular adverse effects when used with fluticasone propionate and salmeterol.

CYP3A4 inhibitor may increase systemic exposure to irinotecan or SN-38. Do not administer unless no therapeutic alternatives.

Concomitant use of strong CYP3A4 inhibitors (such as boceprevir, clarithromycin, conivaptan, indinavir, itraconazole, ketoconazole, lopinavir/ritonavir, nefazodone, nelfinavir, posaconazole, ritonavir, saquinavir, telaprevir, telithromycin, tipranavir/ritonavir, voriconazole) with lomitapide is contraindicated.

Strong CYP 3A4 inhibitor; should not be co-administered due to risk of vasospasm leading to cerebral ischemia and/or ischemia of extremities.

Strong CYP 3A4 inhibitor; rare reports of serious adverse events with ergot alkaloids including vasospasm leading to cerebral ischemia and ischemia of extremities.

CYP3A4 inhibitor; simultaneous use with both CYP2D6 and CYP3A4 inhibitors should be avoided due to increased risk of proarrhythmia.

( 7.2 ) 7.1 Effects of Other Drugs on Ranolazine Strong CYP3A Inhibitors Do not use ranolazine with strong CYP3A inhibitors, including ketoconazole, itraconazole, clarithromycin, nefazodone, nelfinavir, ritonavir, indinavir, and saquinavir [see Contraindications (4) , Clinical Pharmacology (12.3) ].

Concomitant use with ritonavir-boosted saquinavir developed severe hepatocellular toxicity in healthy subjects. Contraindicated.

7 DRUG INTERACTIONS Sildenafil citrate can potentiate the hypotensive effects of nitrates, alpha blockers, and anti-hypertensives ( 4.1 , 5.5 , 7.1 , 7.2 , 7.3 , 12.2 ) With concomitant use of alpha blockers, initiate sildenafil citrate at 25 mg dose ( 2.3 ) CYP3A4 inhibitors (e.g., ritonavir, ketoconazole, itraconazole, erythromycin): Increase sildenafil citrate exposure ( 2.4 , 7.4 , 12.3 ) Ritonavir: Do not exceed a maximum single dose of 25 mg in a 48 hour period ( 2.4 , 5.6 ) Erythromycin or strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, saquinavir): Consider a starting dose of 25 mg ( 2.4 , 7.4 ) 7.1 Nitrates Administration of sildenafil tablets with nitric oxide donors such as organic nitrates or organic nitrites in any form is contraindicated. Co-administration of saquinavir, a strong CYP3A4 inhibitor, resulted in 140% and 210% increases in sildenafil C max and AUC, respectively. Stronger CYP3A4 inhibitors such as ketoconazole or itraconazole could be expected to have greater effects than seen with saquinavir.

7 DRUG INTERACTIONS • Sildenafil can potentiate the hypotensive effects of nitrates, alpha blockers, and anti-hypertensives ( 4.1 , 5.5 , 7.1 , 7.2 , 7.3 , 12.2 ) • With concomitant use of alpha blockers, initiate sildenafil at 25 mg dose ( 2.3 ) • CYP3A4 inhibitors (e.g., ritonavir, ketoconazole, itraconazole, erythromycin): Increase sildenafil exposure ( 2.4 , 7.4 , 12.3 ) o Ritonavir: Do not exceed a maximum single dose of 25 mg in a 48 hour period ( 2.4 , 5.6 ) o Erythromycin or strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, saquinavir): Consider a starting dose of 25 mg ( 2.4 , 7.4 ) 7.1 Nitrates Administration of sildenafil with nitric oxide donors such as organic nitrates or organic nitrites in any form is contraindicated. Co-administration of saquinavir, a strong CYP3A4 inhibitor, resulted in 140% and 210% increases in sildenafil C max and AUC, respectively. Stronger CYP3A4 inhibitors such as ketoconazole or itraconazole could be expected to have greater effects than seen with saquinavir.

Strong CYP3A inhibitor; concomitant use not recommended due to increased suvorexant exposure.

Strong CYP3A inhibitor that substantially increases ticagrelor exposure, increasing risk of dyspnea, bleeding, and other adverse events.

In vivo studies Do not use vardenafil orally disintegrating tablet with moderate and strong CYP3A4 inhibitors such as erythromycin, grapefruit juice, clarithromycin, ketoconazole, itraconazole, indinavir, saquinavir, atazanavir, ritonavir as the systemic concentration of vardenafil is increased in their presence [see Warnings and Precautions (5) and Dosage and Administration ( 2.4 )] .

Strong CYP3A4 inhibitor that may increase DM1 exposure and toxicity. Concomitant use should be avoided or KADCYLA treatment delayed.

No drug interaction studies have been conducted with amlodipine besylate and atorvastatin calcium and other drugs, although studies have been conducted in the individual amlodipine and atorvastatin components, as described below: Amlodipine Increased Risk of Myopathy and Rhabdomyolysis ( 2 , 5.1 , 7.3 , 12.3 ) Cyclosporine, tipranavir plus ritonavir, glecaprevir plus pibrentasvir Avoid atorvastatin Clarithromycin, itraconazole, saquinavir plus ritonavir, darunavir plus ritonavir, fosamprenavir, fosamprenavir plus ritonavir, elbasvir plus grazoprevir,letermovir Do not exceed 20 mg atorvastatin daily Nelfinavir Do not exceed 40 mg atorvastatin daily Lopinavir plus ritonavir, simeprevir, fibric acid derivatives, erythromycin, azole antifungals, lipid-modifying doses of niacin, colchicine Consider the risk/benefit of concomitant use with atorvastatin Other Lipid-Lowering Medications: Increased risk of myopathy (7) . In patients taking saquinavir plus ritonavir, darunavir plus ritonavir, fosamprenavir,fosamprenavir plus ritonavir, elbasvir plus grazoprevir or letermovir, do not exceed atorvastatin 20 mg. Examples: Tipranavir plus ritonavir, glecaprevir plus pibrentasvir, lopinavir plus ritonavir, simeprevir, saquinavir plus ritonavir, darunavir plus ritonavir, fosamprenavir, fosamprenavir plus ritonavir, elbasvir plus grazoprevir, letermovir, nelfinavir, and ledipasvir plus sofosbuvir.

Significantly increases atorvastatin plasma levels. Do not exceed ATORVALIQ 20 mg.

Drug Interactions Associated with Increased Risk of Myopathy/Rhabdomyolysis ( 2.6 , 5.1 , 7 , 12.3 ) Interacting Agents Prescribing Recommendations Cyclosporine, HIV protease inhibitors (tipranavir plus ritonavir), hepatitis C protease inhibitor (telaprevir) Avoid atorvastatin HIV protease inhibitor (lopinavir plus ritonavir) Use with caution and lowest dose necessary Clarithromycin, itraconazole, HIV protease inhibitors (saquinavir plus ritonavir, darunavir plus ritonavir, fosamprenavir, fosamprenavir plus ritonavir) Do not exceed 20 mg atorvastatin daily HIV protease inhibitor (nelfinavir) Hepatitis C protease inhibitor (boceprevir) Do not exceed 40 mg atorvastatin daily • Other Lipid-Lowering Medications: Use with fibrate products or lipid-modifying doses (≥ 1 g/day) of niacin increases the risk of adverse skeletal muscle effects. In patients taking the HIV protease inhibitors saquinavir plus ritonavir, darunavir plus ritonavir, fosamprenavir, or fosamprenavir plus ritonavir, the dose of atorvastatin should not exceed 20 mg and should be used with caution [ see Dosage and Administration ( 2.6 ) and Warnings and Precautions ( 5.1 ) ].

Strong CYP3A inhibitor may increase plasma concentrations of cabazitaxel. Avoid coadministration or consider 25% dose reduction.

Avoid taking a strong CYP3A4 inhibitor (e.g., ketoconazole, itraconazole, clarithromycin, atazanavir, indinavir, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin, voriconazole) while taking COMETRIQ or reduce the dosage of COMETRIQ if concomitant use with strong CYP3A4 inhibitors cannot be avoided [see Dosage and Administration ( 2.2 ), Clinical Pharmacology ( 12.3 )] . Monitor patients for increased toxicity when MRP2 inhibitors (e.g., abacavir, adefovir, cidofovir, furosemide, lamivudine, nevirapine, ritonavir, probenecid, saquinavir, and tenofovir) are co-administered with COMETRIQ [see Clinical Pharmacology ( 12.3 )] .

Increased exposure of saquinavir when used concomitantly with dexlansoprazole may increase toxicity of the antiretroviral drug.

Examples: cyclosporine, gemfibrozil, antiretrovirals (atazanavir, lopinavir, ritonavir, saquinavir, tipranavir), rifampin, eltrombopag Drugs that Cause Constipation Clinical Impact: Increased risk for constipation related adverse reactions and potential for constipation related serious adverse reactions Intervention: Avoid use with other drugs that may cause constipation (see below); loperamide may be used occasionally for acute management of severe diarrhea but avoid chronic use.

Avoid co-administering erlotinib with strong CYP3A4 inhibitors (e.g., boceprevir, clarithromycin, conivaptan, indinavir, itraconazole, ketoconazole, lopinavir/ritonavir, nefazodone, nelfinavir, posaconazole, ritonavir, saquinavir, telithromycin, voriconazole, grapefruit or grapefruit juice) or a combined CYP3A4 and CYP1A2 inhibitor (e.g., ciprofloxacin).

Avoid co-administering erlotinib tablets with strong CYP3A4 inhibitors (e.g., boceprevir, clarithromycin, conivaptan, indinavir, itraconazole, ketoconazole, lopinavir/ritonavir, nefazodone, nelfinavir, posaconazole, ritonavir, saquinavir, telithromycin, voriconazole, grapefruit or grapefruit juice) or a combined CYP3A4 and CYP1A2 inhibitor (e.g., ciprofloxacin).

Co-administration increases saquinavir concentrations (AUC increased by 82%, Cmax by 75%, Cmin by 106%), which may increase toxicity. Clinical and laboratory monitoring recommended; dose reduction should be considered.

Increased exposure of saquinavir when used concomitantly with esomeprazole may increase toxicity.

Increased exposure of saquinavir when used concomitantly with esomeprazole may increase toxicity.

Increased exposure when used concomitantly with esomeprazole may increase toxicity; monitor for potential saquinavir-related toxicities.

Esomeprazole increases saquinavir concentrations significantly (AUC increased by 82%, Cmax by 75%), which may increase toxicity. Clinical and laboratory monitoring recommended; dose reduction should be considered.

Abnormal renal function observed during concurrent use with foscarnet, ritonavir, and saquinavir.

Strong CYP3A4 inhibitor may cause increased plasma concentration of triamcinolone acetonide and adverse reactions.

Increased exposure of saquinavir when used concomitantly with lansoprazole may increase toxicity of the antiretroviral drug.

Increased exposure of saquinavir when used concomitantly with lansoprazole may increase toxicity of the antiretroviral drug.

Loperamide decreases saquinavir exposure by 54%, potentially reducing therapeutic efficacy. Monitor saquinavir efficacy closely.

Strong CYP3A4 inhibitor may increase plasma concentration of triamcinolone leading to adverse reactions.

Causes 56% reduction in midazolam clearance and approximately doubles half-life, significantly prolonging sedation.

Reduces clearance of midazolam by 56%, significantly prolonging sedation through P450-3A4 enzyme inhibition.

Strong CYP3A inhibitor may increase mifepristone plasma concentrations; limit mifepristone dose to 900 mg per day when used together.

CYP3A inhibitor that may increase nifedipine exposure. Careful monitoring and dose adjustment necessary; consider lowest dose.

Strong CYP3A4 inhibitor that significantly increases nimodipine plasma concentration and blood pressure lowering effect. Concomitant administration should generally be avoided.

Increased exposure of saquinavir when used concomitantly with omeprazole may increase toxicity.

Increased exposure of saquinavir when used concomitantly with omeprazole may increase toxicity; monitor for potential saquinavir-related toxicities.

Increased exposure when used concomitantly with omeprazole may increase toxicity. Monitor for potential saquinavir-related toxicities.

Increased exposure of other antiretroviral drugs (e.g., saquinavir) when used concomitantly with omeprazole may increase toxicity [see Clinical Pharmacology (12.3) ] . Avoid concomitant use of TALICIA with amprenavir, indinavir, lopinavir/ritonavir, saquinavir/ritonavir, ritonavir, tipranavir/ritonavir, fosamprenavir/ritonavir, or nelfinavir [see Warnings and Precautions (5.7) ] .

Avoid concomitant use of strong CYP3A inhibitors (e.g., clarithromycin, indinavir, itraconazole, ketoconazole, lopinavir/ritonavir, nefazodone, nelfinavir, posaconazole, ritonavir, saquinavir, telaprevir, telithromycin, and voriconazole).

Increased exposure of saquinavir when used concomitantly with pantoprazole may increase toxicity of the antiretroviral drug.

Increased exposure of saquinavir when used concomitantly with pantoprazole may increase toxicity of the antiretroviral drug.

Increased exposure of saquinavir when used concomitantly with pantoprazole may increase toxicity of the antiretroviral drug.

Increased exposure of saquinavir when used concomitantly with pantoprazole may increase toxicity of the antiretroviral drug.

Increased exposure of saquinavir when used concomitantly with pantoprazole may increase toxicity of the antiretroviral drug.

Strong CYP3A inhibitor increases paricalcitol exposure. Dose adjustment may be necessary; monitor intact PTH and serum calcium closely.

CYP3A4 inhibitor that increases propafenone plasma levels, potentially causing cardiac arrhythmias and proarrhythmia risk.

Increased exposure of saquinavir when used concomitantly with rabeprazole may increase toxicity.

Increased exposure of saquinavir when used concomitantly with rabeprazole may increase toxicity.

7 DRUG INTERACTIONS When co-administering ritonavir with other protease inhibitors (atazanavir, darunavir, fosamprenavir, saquinavir, and tipranavir), see the full prescribing information for that protease inhibitor including important information for drug interactions. HIV-1 Protease Inhibitor: saquinavir ↑ saquinavir See the complete prescribing information for saquinavir for details on co-administration of saquinavir and ritonavir. Saquinavir/ritonavir in combination with rifampin is not recommended due to the risk of severe hepatotoxicity (presenting as increased hepatic transaminases) if the three drugs are given together.

7 DRUG INTERACTIONS When co-administering ritonavir with other protease inhibitors (atazanavir, darunavir, fosamprenavir, saquinavir, and tipranavir), see the full prescribing information for that protease inhibitor including important information for drug interactions. HIV-1 Protease Inhibitor: saquinavir ↑ saquinavir See the complete prescribing information for saquinavir for details on co-administration of saquinavir and ritonavir. Saquinavir/ritonavir in combination with rifampin is not recommended due to the risk of severe hepatotoxicity (presenting as increased hepatic transaminases) if the three drugs are given together.

Strong CYP3A4 inhibitor may increase salmeterol exposure and risk of cardiovascular effects.

Strong CYP3A4/5 inhibitor anticipated to significantly increase saxagliptin plasma concentrations. Limit saxagliptin dosage to 2.5 mg.

Strong CYP3A4/5 inhibitor anticipated to significantly increase saxagliptin plasma concentrations. Dose limitation required.

Strong CYP3A4 inhibitor that increases toremifene steady-state concentration and should be avoided.

Avoid using strong CYP3A inhibitors (e.g., oral ketoconazole, itraconazole, posaconazole, voriconazole, clarithromycin, telithromycin, indinavir, lopinavir, ritonavir, boceprevir, nelfinavir, saquinavir, telaprevir, nefazodone, conivaptan) in patients taking YONDELIS.

Strong CYP3A4 inhibitor may increase triamcinolone plasma concentration and adverse reactions.

P-glycoprotein inhibitor that increases afatinib exposure. Reduce GILOTRIF dose by 10 mg per day if not tolerated.

Caution should be exercised when considering the co-administration of AIRSUPRA with long-term ketoconazole and other known strong CYP3A4 inhibitors (e.g., ritonavir, atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, saquinavir, telithromycin) [see Warnings and Precautions (5.11) ] .

Caution should be exercised when considering the coadministration of BREYNA with long-term ketoconazole and other known strong CYP3A4 inhibitors (e.g., ritonavir, atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, saquinavir, telithromycin) [see Warnings and Precautions (5.9) ] .

Caution should be exercised when considering the coadministration of budesonide inhalation suspension with long- term ketoconazole and other known strong CYP3A4 inhibitors (e.g., ritonavir, atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, saquinavir, telithromycin) [see Warnings and Precautions ( 5.12 ), Clinical Pharmacology ( 12.3 )].

CYP3A4 inhibitor (HIV protease inhibitor) can increase plasma concentration of buprenorphine. Monitoring recommended when transferring to or initiating with SUBLOCADE.

CYP3A4 inhibitor may alter serum levels of calcifediol by inhibiting vitamin D metabolism enzymes. Dose adjustment and monitoring of serum 25-hydroxyvitamin D, PTH, and calcium may be required.

Antivirals: Atazanavir Saquinavir (in patients with decreased renal function) Ritonavir Etravirine Maraviroc Boceprevir (in patients with normal renal function) Didanosine Zidovudine Use With Caution No Dose Adjustment Atazanavir : Both clarithromycin and atazanavir are substrates and inhibitors of CYP3A, and there is evidence of a bi-directional drug interaction (see Atazanavir under “Drugs That Affect Clarithromycin” in the table below) [see Pharmacokinetics (12.3) ] . Saquinavir : Both clarithromycin and saquinavir are substrates and inhibitors of CYP3A and there is evidence of a bi-directional drug interaction (see Saquinavir under “Drugs That Affect Clarithromycin” in the table below) [see Pharmacokinetics (12.3) ] . Antivirals: Atazanavir Ritonavir (in patients with decreased renal function) Saquinavir (in patients with decreased renal function) Etravirine Saquinavir (in patients with normal renal function) Ritonavir (in patients with normal renal function) Use With Caution No Dose Adjustment Atazanavir: When clarithromycin is co-administered with atazanavir, the dose of clarithromycin should be decreased by 50% [see Clinical Pharmacology (12.3) ] .

Coadministration with TYBOST is not recommended because pharmacokinetic data are not available to provide appropriate dosing recommendations.

HIV protease inhibitor that inhibits CYP3A4 and may increase cyclosporine concentrations. Care should be exercised; dosage monitoring required.

Closely monitor patients for signs of reduced effectiveness when deferasirox is administered with drugs metabolized by CYP3A4 (e.g., alfentanil, aprepitant, budesonide, buspirone, conivaptan, cyclosporine, darifenacin, darunavir, dasatinib, dihydroergotamine, dronedarone, eletriptan, eplerenone, ergotamine, everolimus, felodipine, fentanyl, hormonal contraceptive agents, indinavir, fluticasone, lopinavir, lovastatin, lurasidone, maraviroc, midazolam, nisoldipine, pimozide, quetiapine, quinidine, saquinavir, sildenafil, simvastatin, sirolimus, tacrolimus, tolvaptan, tipranavir, triazolam, ticagrelor, and vardenafil) [ see Clinical Pharmacology (12.3)].

Increases digoxin serum concentration by 27% and AUC by 49%. Requires monitoring and dose adjustment.

Administer moderate CYP3A4 inhibitors (e.g., saquinavir, nefazodone, fluconazole, grapefruit juice, fluoxetine, fluvoxamine, zileuton, clotrimazole) with caution.

Caution should be exercised when concomitantly administering CARDURA XL with a strong CYP 3A4 inhibitor, such as atazanavir, clarithromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin, or voriconazole [see Clinical Pharmacology (12.3) ] .

7 DRUG INTERACTIONS • CYP3A Inhibitors: In post-MI HFrEF patients, do not exceed 25 mg once daily when used with moderate CYP3A inhibitors (e.g., verapamil, erythromycin, saquinavir, fluconazole).

7.2 Pharmacokinetic Drug Interactions Table 3: Effect of Fexinidazole on other Drugs Drugs Metabolized by Cytochrome P450 (CYP) 3A4/5 Examples (not fully inclusive): Lovastatin, simvastatin, nisoldipine, saquinavir, midazolam, certain hormonal contraceptives (e.g., birth control pills, skin patches, implant) Clinical Impact Fexinidazole is considered a moderate CYP3A4/5 inducer [see Clinical Pharmacology (12.3) ] .

Caution should be exercised when considering the coadministration of budesonide and formoterol fumarate dihydrate with long-term ketoconazole and other known strong CYP3A4 inhibitors (e.g., ritonavir, atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, saquinavir, telithromycin) [see Warnings and Precautions (5.9) ] .

Caution is recommended when administering imatinib mesylate tablets with strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, clarithromycin, atazanavir, indinavir, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin, and voriconazole).

Cobicistat Elvitegravir (ritonavir-boosted) Ombitasvir/Paritaprevir/Ritonavir with or without Dasabuvir Ritonavir Saquinavir (unboosted) a Monitor for adverse reactions. Antivirals Cobicistat Darunavir (ritonavir-boosted) Elvitegravir (ritonavir-boosted) Fosamprenavir (ritonavir-boosted) Indinavira Ombitasvir/Paritaprevir/Ritonavir with or without Dasabuvir Ritonavir Saquinavir Monitor for adverse reactions. For, cobicistat, elvitegravir, indinavir, ombitasvir/paritaprevir/ ritonavir with or without dasabuvir, ritonavir, and saquinavir, see also Table 1.

Reduces clearance of midazolam by 56% and approximately doubles half-life, resulting in prolonged sedation.

Caution should be exercised when considering the co-administration of mometasone furoate nasal spray with long-term ketoconazole and other known strong CYP3A4 inhibitors (e.g., ritonavir, cobicistat-containing products, atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, saquinavir, telithromycin) [see Clinical Pharmacology (12.3) ] .

Caution should be exercised when considering the coadministration of ASMANEX HFA with long-term ketoconazole and other known strong CYP3A4 inhibitors (e.g., ritonavir, cobicistat-containing products, atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, saquinavir, telithromycin) [see Warnings and Precautions (5.6) and Clinical Pharmacology (12.3) ] .

Caution should be exercised when considering the coadministration of DULERA with long-term ketoconazole and other known strong CYP3A4 inhibitors (e.g., ritonavir, cobicistat-containing products, atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, saquinavir, telithromycin) [see Warnings and Precautions (5.8) and Clinical Pharmacology (12.3) ] .

Caution should be exercised when considering the coadministration of mometasone furoate monohydrate nasal spray with long-term ketoconazole and other known strong CYP3A4 inhibitors (e.g., ritonavir, cobicistat-containing products, atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, saquinavir, telithromycin) [see Clinical Pharmacology (12.3) ] .

Moderate (e.g., fluconazole, atazanavir, aprepitant, diltiazem, erythromycin) and Strong (e.g., itraconazole, ketoconazole, clarithromycin, ritonavir, saquinavir) CYP3A Inhibitors Clinical Impact Increase in plasma naldemedine concentrations [see Clinical Pharmacology (12.3) ] Intervention Monitor for potential naldemedine-related adverse reactions [see Adverse Reactions (6.1) ] .

Caution should be exercised when paclitaxel is concomitantly administered with known substrates (e.g., midazolam, buspirone, felodipine, lovastatin, eletriptan, sildenafil, simvastatin, and triazolam), inhibitors (e.g., atazanavir, clarithromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, saquinavir, and telithromycin), and inducers (e.g., rifampin and carbamazepine) of CYP3A4. Potential interactions between paclitaxel, a substrate of CYP3A4, and protease inhibitors (ritonavir, saquinavir, indinavir, and nelfinavir), which are substrates and/or inhibitors of CYP3A4, have not been evaluated in clinical trials.

Rifabutin induces CYP3A enzymes and may reduce plasma concentrations of saquinavir, potentially reducing its efficacy.

Strong CYP3A4 inhibitor that may increase midostaurin concentrations and risk of toxicity. Monitor for increased adverse reactions, especially during first week of administration.

Prevention or Management Saquinavir (CYP3A substrate and inhibitor) Use VOQUEZNA TRIPLE PAK with caution. See saquinavir prescribing information for instructions when saquinavir (with or without ritonavir) is co-administered with clarithromycin. Prevention or Management Saquinavir (CYP3A substrate and inhibitor) Use VOQUEZNA TRIPLE PAK with caution.

Protease Inhibitors: saquinavir (soft gelatin capsules) ↑ saquinavir Appropriate dosing recommendations for this combination, with or without ritonavir, with respect to efficacy and safety have not been established. In a clinical study, saquinavir 1200 mg coadministered with REYATAZ 400 mg and tenofovir DF 300 mg (all given once daily), and nucleoside analogue reverse transcriptase inhibitors did not provide adequate efficacy [see Clinical Studies (14.2) ] .

Protease Inhibitors: saquinavir (soft gelatin capsules) ↑ saquinavir Appropriate dosing recommendations for this combination, with or without ritonavir, with respect to efficacy and safety have not been established. In a clinical study, saquinavir 1200 mg coadministered with atazanavir 400 mg and tenofovir DF 300 mg (all given once daily), and nucleoside analogue reverse transcriptase inhibitors did not provide adequate efficacy [see Clinical Studies (14.2)] .

Other potent inhibitors of CYP3A4 (e.g., itraconazole, clarithromycin, nefazadone, ritonavir, saquinavir, nelfinavir, indinavir, atanazavir and telithromycin) would be expected to have similar effects.

saquinavir ↓ darunavir ↔saquinavir Appropriate doses of the combination have not been established. Hence, it is not recommended to co-administer saquinavir and darunavir, with or without ritonavir.

saquinavir ↓ darunavir ↔ saquinavir Appropriate doses of the combination have not been established. Hence, it is not recommended to co-administer saquinavir and darunavir, with or without ritonavir.

Protease inhibitor: Saquinavir ↓ saquinavir * Appropriate doses of the combination of efavirenz and saquinavir/ritonavir with respect to safety and efficacy have not been established.

Protease inhibitor: saquinavir ↓ saquinavir Appropriate doses of the combination of EFV and saquinavir/ritonavir with respect to safety and efficacy have not been established.

nelfinavir (without ritonavir) ritonavir saquinavir/ritonavir tipranavir/ritonavir ↑ nelfinavir ↓ etravirine ↓ etravirine ↓ etravirine Concomitant use of etravirine tablets with nelfinavir without low- dose ritonavir may cause a significant alteration in the plasma concentration of nelfinavir. The mean systemic exposure (AUC) of etravirine was reduced when etravirine tablets were co-administered with saquinavir/ ritonavir. Because the reduction in the mean systemic exposures of etravirine in the presence of saquinavir/ritonavir is similar to the reduction in mean systemic exposures of etravirine in the presence of darunavir/ritonavir, etravirine tablets and saquinavir/ritonavir can be co-administered without dose adjustments.

(See CLINICAL PHARMACOLOGY: Drug Interaction Studies .) Saquinavir : Fluconazole increases the AUC of saquinavir by approximately 50%, C max by approximately 55%, and decreases the clearance of saquinavir by approximately 50% due to inhibition of saquinavir’s hepatic metabolism by CYP3A4 and inhibition of P-glycoprotein. Dosage adjustment of saquinavir may be necessary.

HIV protease inhibitor: Saquinavir a Fosamprenavir calcium: ↓ Amprenavir Effect on saquinavir is not well established.

Carbamazepine, felbamate, lamotrigine, topiramate, oxcarbazepine, lacosamide Antiplatelets Ticagrelor Antilipidemic agents Atorvastatin, fluvastatin, simvastatin Antiviral agents Efavirenz, lopinavir/ritonavir, indinavir, nelfinavir, ritonavir, saquinavir Fosamprenavir: phenytoin when given with fosamprenavir alone may decrease the concentration of amprenavir, the active metabolite.

Antivirals indinavir, maraviroc, saquinavir Beta Blockers nadolol Calcium Channel Blockers felodipine, nisoldipine other dihydropyridines, verapamil Calcium channel blockers can have a negative inotropic effect which may be additive to those of ketoconazole.

Examples Alfentanil, avanafil, buspirone, conivaptan b , dabigatran etexilate, darifenacin, darunavir, digoxin, ebastine, everolimus, fexofenadine, ibrutinib, lomitapide, lovastatin, lurasidone, midazolam, naloxegol, nisoldipine, saquinavir, simvastatin, sirolimus, tacrolimus, tipranavir b , triazolam, and vardenafil. Examples Antivirals (e.g., ritonavir, ritonavir-boosted darunavir, ritonavir-boosted fosamprenavir, saquinavir) Glucocorticoid and progesterone receptor antagonists (e.g., mifepristone) Strong CYP3A4 Inducers Clinical Impact May decrease plasma concentrations of levoketoconazole and reduce the efficacy of RECORLEV Prevention or Management Administration of strong enzyme inducers of CYP3A4 with RECORLEV is not recommended.

HIV-1 Protease Inhibitor: saquinavir ↑ saquinavir The saquinavir dose is 1000 mg twice daily, when co-administered with lopinavir and ritonavir 400/100 mg twice daily. Lopinavir and ritonavir once daily has not been studied in combination with saquinavir.

Co-administration of other strong CYP3A4 inhibitors (e.g., ritonavir, atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, saquinavir, telithromycin, cobicistat-containing products) with triamcinolone acetonide injectable suspension may cause increased plasma concentration of triamcinolone leading to adverse reactions (see ADVERSE REACTIONS ).

Paradoxical Effects of Antiretroviral Agents on Methadone Hydrochloride Tablets Concurrent use of certain antiretroviral agents with CYP3A4 inhibitory activity, alone and in combination, such as abacavir, amprenavir, darunavir+ritonavir, efavirenz, nelfinavir, nevirapine, ritonavir, telaprevir, lopinavir+ritonavir, saquinavir+ritonavir, and tipranavir+ritonavir, has resulted in increased clearance or decreased plasma levels of methadone.

Paradoxical Effects of Anti-Retroviral Agents on Methadone Concurrent use of certain protease inhibitors with CYP3A4 inhibitory activity, alone and in combination, such as abacavir, amprenavir, darunavir+ritonavir, efavirenz, nelfinavir, nevirapine, ritonavir, telaprevir, lopinavir+ritonavir, saquinavir+ritonavir, and tipranvir+ritonavir, has resulted in increased clearance or decreased plasma levels of methadone.

• Increased exposure of other antiretroviral drugs (e.g., saquinavir) when used concomitantly with esomeprazole magnesium may increase toxicity [see Clinical Pharmacology (12.3) ] . S aquinavir: See the prescribing information for saquinavir for monitoring of potential saquinavir-related toxicities.

Saquinavir ↑ nelfinavir ↑ saquinavir Concentrations of both saquinavir and nelfinavir were increased when the two agents were coadministered.

Saquinavir/Ritonavir The interaction between nevirapine and saquinavir/ritonavir has not been evaluated The appropriate doses of the combination of nevirapine and saquinavir/ritonavir with respect to safety and efficacy have not been established.

Warfarin Increased and decreased PT/INR responses have been reported when phenytoin is coadministered with warfarin Other Corticosteroids, doxycycline, estrogens, furosemide, oral contraceptives, paroxetine, quinidine, rifampin, sertraline, theophylline, and vitamin D Drugs whose level is decreased by phenytoin Anticoagulants Apixaban, dabigatran, edoxaban, rivaroxaban Antiepileptic drugs The effect of phenytoin on phenobarbital, valproic acid and sodium valproate serum levels is unpredictable Carbamazepine, felbamate, lacosamide, lamotrigine, topiramate, oxcarbazepine Antilipidemic agents Atorvastatin, fluvastatin, simvastatin Antiplatelets Ticagrelor Antiviral agents Efavirenz, lopinavir/ritonavir, indinavir, nelfinavir, ritonavir, saquinavir Fosamprenavir: phenytoin when given with fosamprenavir alone may decrease the concentration of amprenavir, the active metabolite.

Warfarin Increased and decreased PT/INR responses have been reported when phenytoin is coadministered with warfarin Other Corticosteroids, doxycycline, estrogens, furosemide, oral contraceptives, paroxetine, quinidine, rifampin, sertraline, theophylline, and vitamin D Drugs whose level is decreased by phenytoin Antiepileptic drugs a Carbamazepine, felbamate, lamotrigine, topiramate, oxcarbazepine Antilipidemic agents Atorvastatin, fluvastatin, simvastatin Antiviral agents Efavirenz, lopinavir/ritonavir, indinavir, nelfinavir, ritonavir, saquinavir Fosamprenavir: phenytoin when given with fosamprenavir alone may decrease the concentration of amprenavir, the active metabolite.

Other boosted PIs (atazanavir/ritonavir, fosamprenavir/ritonavir, saquinavir/ritonavir, tipranavir/ritonavir) ↑ rilpivirine ↔ boosted PI Concomitant use of rilpivirine tablets with boosted PIs may cause an increase in the plasma concentrations of rilpivirine (inhibition of CYP3A enzymes).

Other boosted PIs (atazanavir/ritonavir, fosamprenavir/ritonavir, saquinavir/ritonavir, tipranavir/ritonavir) ↑ rilpivirine ↔ boosted PI Concomitant use of EDURANT or EDURANT PED with boosted PIs may cause an increase in the plasma concentrations of rilpivirine (inhibition of CYP3A enzymes).

Lopinavir ↓ Lopinavir Saquinavir ↓ Saquinavir Protease Inhibitors (co-administered with 100 mg of ritonavir): Atazanavir ↓ Atazanavir ↑ Tipranavir Virus Integrase Strand Transfer Inhibitors (INSTI): Raltegravir ↓ Raltegravir No dose adjustment is needed for 400 mg twice daily dosing regimen of raltegravir.

Table 2: Examples of CYP450 Interactions with Warfarin Enzyme Inhibitors Inducers CYP2C9 amiodarone, capecitabine, cotrimoxazole, etravirine, fluconazole, fluvastatin, fluvoxamine, metronidazole, miconazole, oxandrolone, sulfinpyrazone, tigecycline, voriconazole, zafirlukast aprepitant, bosentan, carbamazepine, phenobarbital, rifampin CYP1A2 acyclovir, allopurinol, caffeine, cimetidine, ciprofloxacin, disulfiram, enoxacin, famotidine, fluvoxamine, methoxsalen, mexiletine, norfloxacin, oral contraceptives, phenylpropanolamine, propafenone, propranolol, terbinafine, thiabendazole, ticlopidine, verapamil, zileuton montelukast, moricizine, omeprazole, phenobarbital, phenytoin, cigarette smoking CYP3A4 alprazolam, amiodarone, amlodipine, amprenavir, aprepitant, atorvastatin, atazanavir, bicalutamide, cilostazol, cimetidine, ciprofloxacin, clarithromycin, conivaptan, cyclosporine, darunavir/ritonavir, diltiazem, erythromycin, fluconazole, fluoxetine, fluvoxamine, fosamprenavir, imatinib, indinavir, isoniazid, itraconazole, ketoconazole, lopinavir/ritonavir, nefazodone, nelfinavir, nilotinib, oral contraceptives, posaconazole, ranitidine, ranolazine, ritonavir, saquinavir, telithromycin, tipranavir, voriconazole, zileuton armodafinil, amprenavir, aprepitant, bosentan, carbamazepine, efavirenz, etravirine, modafinil, nafcillin, phenytoin, pioglitazone, prednisone, rifampin, rufinamide 7.3 Drugs that Increase Bleeding Risk Examples of drugs known to increase the risk of bleeding are presented in Table 3.

Table 2: Examples of CYP450 Interactions with Warfarin Enzyme Inhibitors Inducers CYP2C9 amiodarone, capecitabine, cotrimoxazole, etravirine, fluconazole, fluvastatin, fluvoxamine, metronidazole, miconazole, oxandrolone, sulfinpyrazone, tigecycline, voriconazole, zafirlukast aprepitant, bosentan, carbamazepine, phenobarbital, rifampin CYP1A2 acyclovir, allopurinol, caffeine, cimetidine, ciprofloxacin, disulfiram, enoxacin, famotidine, fluvoxamine, methoxsalen, mexiletine, norfloxacin, oral contraceptives, phenylpropanolamine, propafenone, propranolol, terbinafine, thiabendazole, ticlopidine, verapamil, zileuton montelukast, moricizine, omeprazole, phenobarbital, phenytoin, cigarette smoking CYP3A4 alprazolam, amiodarone, amlodipine, amprenavir, aprepitant, atorvastatin, atazanavir, bicalutamide, cilostazol, cimetidine, ciprofloxacin, clarithromycin, conivaptan, cyclosporine, darunavir/ritonavir, diltiazem, erythromycin, fluconazole, fluoxetine, fluvoxamine, fosamprenavir, imatinib, indinavir, isoniazid, itraconazole, ketoconazole, lopinavir/ritonavir, nefazodone, nelfinavir, nilotinib, oral contraceptives, posaconazole, ranitidine, ranolazine, ritonavir, saquinavir, telithromycin, tipranavir, voriconazole, zileuton armodafinil, amprenavir, aprepitant, bosentan, carbamazepine, efavirenz, etravirine, modafinil, nafcillin, phenytoin, pioglitazone, prednisone, rifampin, rufinamide 7.3 Drugs that Increase Bleeding Risk Examples of drugs known to increase the risk of bleeding are presented in Table 3 .