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Fosnetupitant and Palonosetron

Medically reviewed by Drugs.com. Last updated on Nov 16, 2023.

Pronunciation

(fos net UE pi tant & pal oh NOE se tron)

Index Terms

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Solution, Intravenous:

Akynzeo: Fosnetupitant chloride 235 mg and palonosetron hydrochloride 0.25 mg per 20 mL (20 mL) [contains edetate disodium]

Solution Reconstituted, Intravenous:

Akynzeo: Fosnetupitant chloride 235 mg and palonosetron hydrochloride 0.25 mg (1 ea) [contains edetate disodium]

Detailed Fosnetupitant / palonosetron dosage information

Brand Names: U.S.

Pharmacologic Category

Pharmacology

Fosnetupitant is a prodrug of netupitant, a selective substance P/neurokinin (NK1) receptor antagonist, which augments the antiemetic activity of 5-HT3 receptor antagonists and corticosteroids to inhibit acute and delayed chemotherapy-induced emesis. Palonosetron is a selective 5-HT3 receptor antagonist, which blocks serotonin, both on vagal nerve terminals in the periphery and centrally in the chemoreceptor trigger zone. Palonosetron inhibits the cross-talk between the 5-HT3 and NK1 receptors. The combination of palonosetron and netupitant works synergistically to inhibit substance P response to a greater extent than either agent alone (Aapro 2014).

Distribution

Vd: Fosnetupitant: 296 ± 535 L; Palonosetron: 594 ± 239 L

Metabolism

Fosnetupitant is a prodrug and is converted by hydrolysis to netupitant; Netupitant is metabolized extensively hepatic via CYP3A4 (major), CYP2C9 (minor) and CYP2D6 (minor); forms active metabolites M1, M2, and M3

Palonosetron is ~50% metabolized to relatively inactive metabolites (N-oxide-palonosetron and 6-S-hydroxy-palonosetron); CYP2D6, 3A4, and 1A2 contribute to metabolism

Excretion

Fosnetupitant: Fosnetupitant is a prodrug of netupitant (plasma fosnetupitant concentrations rapidly decline shortly after infusion); Netupitant: Feces (~71%); urine (~4%); Palonosetron: Feces (5% to 8%); urine (85% to 93%; 40% as unchanged drug)

Time to Peak

At end of the 30-minute infusion

Half-Life Elimination

Fosnetupitant: 0.75 ± 0.4 hours; Netupitant: 144 ± 73 hours; Palonosetron: 58 ± 27 hours

Protein Binding

Fosnetupitant: 92% to 95%; Palonosetron: ~62%

Special Populations: Hepatic Function Impairment

Fosnetupitant is a prodrug of netupitant. For netupitant, the mean AUC was 67% higher and the mean Cmax was 40% higher in patients with mild hepatic impairment. The mean AUC was 86% higher and the mean Cmax was 41% higher in patients with moderate impairment. For palonosetron, the AUC was 33% higher in patients with mild hepatic impairment and 62% higher in patients with moderate impairment; the mean Cmax was 14% higher in patients with mild hepatic impairment.

Special Populations: Gender

Fosnetupitant is a prodrug of netupitant. For netupitant, the Cmax was 35% higher in females than in males while the AUC was similar between males and females. For palonosetron, the mean AUC was 35% higher and the mean Cmax was 26% higher in females than in males.

Use: Labeled Indications

Chemotherapy-induced nausea and vomiting: Prevention of acute and delayed nausea and vomiting associated with initial and repeat courses of highly emetogenic chemotherapy (in combination with dexamethasone).

Limitations of use: Has not been studied for the prevention of nausea and vomiting associated with anthracycline plus cyclophosphamide (AC) chemotherapy.

Contraindications

There are no contraindications listed in the manufacturer's labeling.

Dosing: Adult

Highly emetogenic chemotherapy (including cisplatin-based): IV: Fosnetupitant 235 mg and palonosetron 0.25 mg 30 minutes before chemotherapy on day 1. Note: Antiemetic regimen also includes dexamethasone 12 mg administered 30 minutes before chemotherapy on day 1, and 8 mg once daily on days 2 to 4.

Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.

Dosing: Geriatric

Refer to adult dosing.

Reconstitution

Injection solution: Prepare an infusion vial or bag filled with 30 mL of D5W or NS. Add entire volume of the fosnetupitant/palonosetron solution from the vial into the infusion vial or bag containing 30 mL of D5W or NS to a total vial/bag volume of 50 mL. Gently invert the vial or bag to mix completely.

Powder for injection: Reconstitute by slowly adding 20 mL of D5W or NS to the vial, directing solution toward the wall of the vial to avoid foaming. Swirl the vial gently. Prepare an infusion vial or bag filled with 30 mL of D5W or NS. Add entire volume of the fosnetupitant/palonosetron reconstituted solution to the infusion vial or bag containing 30 mL of D5W or NS to a total vial/bag volume of 50 mL. Gently invert the vial or bag to mix completely.

Administration

IV: Infuse over 30 minutes starting 30 minutes before chemotherapy. Flush infusion line (with the same solution as used for dilution) after administration of fosnetupitant and palonosetron to ensure complete administration. If the same IV line is used for sequential administration of other medications, flush the line with NS before and after fosnetupitant and palonosetron administration.

Storage

Injection solution: Store intact vials in carton at 20°C to 25°C (68°F to 77°F); protect from light. Store solutions diluted for infusion at room temperature; the total time from infusion preparation to the start of the infusion should not exceed 24 hours.

Powder for injection: Store intact vials in carton at 2°C to 8°C (35.6°F to 46.4°F); protect from light. Store reconstituted solutions and solutions diluted for infusion at room temperature; the total time from reconstitution to the start of the infusion should not exceed 24 hours.

Drug Interactions

Abemaciclib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Abemaciclib. Management: Monitor for increased abemaciclib toxicities if combined with moderate CYP3A4 inhibitors. Consider reducing the abemaciclib dose in 50 mg decrements if necessary. Monitor therapy

Acalabrutinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Acalabrutinib. Management: Reduce acalabrutinib dose to 100 mg once daily with concurrent use of a moderate CYP3A4 inhibitor. Monitor patient closely for both acalabrutinib response and evidence of adverse effects with any concurrent use. Consider therapy modification

Alfentanil: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Alfentanil. Management: If use of alfentanil and moderate CYP3A4 inhibitors is necessary, consider dosage reduction of alfentanil until stable drug effects are achieved. Frequently monitor patients for respiratory depression and sedation when these agents are combined. Consider therapy modification

Alfuzosin: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Alfuzosin. Monitor therapy

Alitretinoin (Systemic): CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Alitretinoin (Systemic). Monitor therapy

AmLODIPine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of AmLODIPine. Monitor therapy

Apixaban: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Apixaban. Monitor therapy

Apomorphine: Antiemetics (5HT3 Antagonists) may enhance the hypotensive effect of Apomorphine. Avoid combination

Aprepitant: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Aprepitant. Avoid combination

ARIPiprazole: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of ARIPiprazole. Management: Monitor for increased aripiprazole pharmacologic effects. Aripiprazole dose adjustments may or may not be required based on concomitant therapy, indication, or dosage form. Consult full interaction monograph for specific recommendations. Monitor therapy

ARIPiprazole Lauroxil: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of ARIPiprazole Lauroxil. Monitor therapy

Asunaprevir: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Asunaprevir. Avoid combination

Avanafil: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Avanafil. Management: The maximum avanafil dose is 50 mg per 24-hour period when used together with a moderate CYP3A4 inhibitor. Patients receiving such a combination should also be monitored more closely for evidence of adverse effects (eg, hypotension, syncope, priapism). Consider therapy modification

Avapritinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Avapritinib. Management: Avoid use of moderate CYP3A4 inhibitors with avapritinib. If this combination cannot be avoided, reduce the avapritinib dose from 300 mg once daily to 100 mg once daily. Consider therapy modification

Axitinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Axitinib. Monitor therapy

Barnidipine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Barnidipine. Monitor therapy

Benzhydrocodone: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Benzhydrocodone. Specifically, the concentration of hydrocodone may be increased. Monitor therapy

Blonanserin: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Blonanserin. Monitor therapy

Bortezomib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Bortezomib. Monitor therapy

Bosutinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Bosutinib. Avoid combination

Brexpiprazole: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Brexpiprazole. Management: The brexpiprazole dose should be reduced to 25% of usual if used together with both a moderate CYP3A4 inhibitor and a strong or moderate CYP2D6 inhibitor, or if a moderate CYP3A4 inhibitor is used in a CYP2D6 poor metabolizer. Monitor therapy

Brigatinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Brigatinib. Management: Avoid concurrent use of brigatinib with moderate CYP3A4 inhibitors when possible. If such a combination cannot be avoided, reduce the dose of brigatinib by approximately 40% (ie, from 180 mg to 120 mg, from 120 mg to 90 mg, or from 90 mg to 60 mg). Consider therapy modification

Bromocriptine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Bromocriptine. Management: The bromocriptine dose should not exceed 1.6 mg daily with use of a moderate CYP3A4 inhibitor. The Cycloset brand specifically recommends this dose limitation, but other bromocriptine products do not make such specific recommendations. Consider therapy modification

Budesonide (Oral Inhalation): CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Budesonide (Oral Inhalation). Monitor therapy

Budesonide (Systemic): CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Budesonide (Systemic). Management: Avoid the concomitant use of CYP3A4 inhibitors and oral budesonide. If patients receive both budesonide and CYP3A4 inhibitors, they should be closely monitored for signs and symptoms of corticosteroid excess. Consider therapy modification

Budesonide (Topical): CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Budesonide (Topical). Avoid combination

Cabozantinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Cabozantinib. Monitor therapy

Cannabidiol: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Cannabidiol. Monitor therapy

Cannabis: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Cannabis. More specifically, tetrahydrocannabinol and cannabidiol serum concentrations may be increased. Monitor therapy

Cilostazol: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Cilostazol. Management: Consider reducing the cilostazol dose to 50 mg twice daily in adult patients who are also receiving moderate inhibitors of CYP3A4. Consider therapy modification

Cobimetinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Cobimetinib. Management: Avoid this combination when possible. If concurrent short term (14 days or less) use cannot be avoided, reduce the cobimetinib dose from 60 mg to 20 mg daily. Avoid concomitant use in patients already receiving reduced cobimetinib doses. Consider therapy modification

Codeine: CYP3A4 Inhibitors (Moderate) may increase serum concentrations of the active metabolite(s) of Codeine. Monitor therapy

Colchicine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Colchicine. Management: Reduce colchicine dose as directed when using with a moderate CYP3A4 inhibitor, and increase monitoring for colchicine-related toxicity. See interaction monograph for details. Use extra caution in patients with impaired renal and/or hepatic function. Consider therapy modification

Copanlisib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Copanlisib. Monitor therapy

Crizotinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Crizotinib. Monitor therapy

CYP3A4 Inducers (Moderate): May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

CYP3A4 Inducers (Strong): May decrease serum concentrations of the active metabolite(s) of Fosnetupitant. Avoid combination

CYP3A4 Substrates (High risk with Inhibitors): Fosnetupitant may increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Dabrafenib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Seek alternatives to concomitant therapy when possible. If concomitant therapy cannot be avoided, monitor for reduced clinical effects of the CYP3A4 substrate. Consider therapy modification

Dapoxetine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Dapoxetine. Management: The dose of dapoxetine should be limited to 30 mg per day when used together with a moderate inhibitor of CYP3A4. Consider therapy modification

Darifenacin: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Darifenacin. Monitor therapy

Deferasirox: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Deflazacort: CYP3A4 Inhibitors (Moderate) may increase serum concentrations of the active metabolite(s) of Deflazacort. Management: Administer one third of the recommended deflazacort dose when used together with a strong or moderate CYP3A4 inhibitor. Consider therapy modification

DexAMETHasone (Systemic): Fosnetupitant may increase the serum concentration of DexAMETHasone (Systemic). Management: Decrease dexamethasone doses to 12 mg on day 1, and if needed based on the emetic potential of the regimen, 8 mg daily on days 2 to 4 of chemotherapy when administered with fosnetupitant. Consider therapy modification

Disopyramide: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Disopyramide. Monitor therapy

Dofetilide: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Dofetilide. Monitor therapy

Domperidone: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Domperidone. Avoid combination

DOXOrubicin (Conventional): CYP3A4 Inhibitors (Moderate) may increase the serum concentration of DOXOrubicin (Conventional). Management: Seek alternatives to moderate CYP3A4 inhibitors in patients treated with doxorubicin whenever possible. Prescribing information for at least one doxorubicin product recommends that these combinations be avoided. Consider therapy modification

Dronabinol: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Dronabinol. Monitor therapy

Eletriptan: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Eletriptan. Management: The use of eletriptan within 72 hours of a moderate CYP3A4 inhibitor should be avoided. Consider therapy modification

Elexacaftor, Tezacaftor, and Ivacaftor: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Elexacaftor, Tezacaftor, and Ivacaftor. Management: When combined with moderate CYP3A4 inhibitors, two elexacaftor/tezacaftor/ivacaftor (100 mg/50 mg/75 mg) tablets should be given in the morning, every other day. Ivacaftor (150 mg) should be given in the morning, every other day on alternate days. Consider therapy modification

Eliglustat: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Eliglustat. Management: Reduce eliglustat dose to 84 mg daily in CYP2D6 EMs when used with moderate CYP3A4 inhibitors. Use in CYP2D6 EMs who are also taking strong or moderate CYP2D6 inhibitors is contraindicated. Avoid use of moderate CYP3A4 inhibitors in CYP2D6 IMs or PMs. Consider therapy modification

Encorafenib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Encorafenib. Management: Avoid use of encorafenib and moderate CYP3A4 inhibitors when possible. If combined, decrease the encorafenib dose from 450 mg to 225 mg; 300 mg to 150 mg; and 225 mg or 150 mg to 75 mg. Resume prior dose once inhibitor discontinued for 3 to 5 half-lives. Consider therapy modification

Entrectinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Entrectinib. Management: Avoid moderate CYP3A4 inhibitors during treatment with entrectinib. Reduce dose to 200 mg/day if combination cannot be avoided in adults and those 12 yrs of age or older with a BSA of at least 1.5 square meters. Avoid if BSA is less than 1.5 square meters Consider therapy modification

Eplerenone: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Eplerenone. Management: If coadministered with moderate CYP3A4 inhibitors, the max dose of eplerenone is 25 mg daily if used for heart failure; if used for hypertension initiate eplerenone 25 mg daily, titrate to max 25 mg twice daily. Consider therapy modification

Erdafitinib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Estrogen Derivatives: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Estrogen Derivatives. Monitor therapy

Everolimus: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Everolimus. Monitor therapy

Fedratinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Fedratinib. Monitor therapy

FentaNYL: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of FentaNYL. Management: Consider fentanyl dose reductions when combined with a moderate CYP3A4 inhibitor. Monitor for respiratory depression and sedation. Upon discontinuation of a CYP3A4 inhibitor, consider a fentanyl dose increase; monitor for signs and symptoms of withdrawal. Consider therapy modification

Flibanserin: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Flibanserin. Management: Use of flibanserin with moderate CYP3A4 inhibitors is contraindicated. If starting flibanserin, start 2 weeks after the last dose of the CYP3A4 inhibitor. If starting a CYP3A4 inhibitor, start 2 days after the last dose of flibanserin. Avoid combination

Fluticasone (Oral Inhalation): CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Fluticasone (Oral Inhalation). Monitor therapy

Fosaprepitant: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Fosaprepitant. Avoid combination

Gilteritinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Gilteritinib. Monitor therapy

GuanFACINE: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of GuanFACINE. Management: Reduce the extended-release guanfacine dose 50% when combined with a moderate CYP3A4 inhibitor. Monitor for increased guanfacine toxicities when these agents are combined. Consider therapy modification

Halofantrine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Halofantrine. Management: Extreme caution, with possibly increased monitoring of ECGs, should be used if halofantrine is combined with moderate CYP3A4 inhibitors. Monitor therapy

HYDROcodone: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of HYDROcodone. Monitor therapy

Ibrutinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Ibrutinib. Management: When treating B-cell malignancies, decrease ibrutinib to 280 mg daily when combined with moderate CYP3A4 inhibitors. When treating graft versus host disease, monitor patients closely and reduce the ibrutinib dose as needed based on adverse reactions. Consider therapy modification

Ifosfamide: CYP3A4 Inhibitors (Moderate) may decrease serum concentrations of the active metabolite(s) of Ifosfamide. Monitor therapy

Imatinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Imatinib. Monitor therapy

Ivabradine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Ivabradine. Avoid combination

Ivacaftor: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Ivacaftor. Management: Ivacaftor dose reductions may be required; consult full drug interaction monograph content for age- and weight-specific dosage recommendations. Consider therapy modification

Ivosidenib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Ivosidenib. Management: Avoid use of moderate CYP3A4 inhibitors with ivosidenib whenever possible. If combined, monitor for increased ivosidenib toxicities. Consider therapy modification

Lapatinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Lapatinib. Monitor therapy

Larotrectinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Larotrectinib. Monitor therapy

Lefamulin: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Lefamulin. Management: Monitor for lefamulin adverse effects during coadministration of lefamulin tablets with moderate CYP3A4 inhibitors. Monitor therapy

Lemborexant: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Lemborexant. Avoid combination

Lercanidipine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Lercanidipine. Monitor therapy

Levamlodipine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Levamlodipine. Monitor therapy

Lomitapide: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Lomitapide. Avoid combination

Lorlatinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Lorlatinib. Monitor therapy

Lumateperone: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Lumateperone. Avoid combination

Lurasidone: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Lurasidone. Management: US labeling recommends reducing lurasidone dose by 50% with a moderate CYP3A4 inhibitor and initiating 20 mg/day, max 80 mg/day. Some non-US labels recommend initiating lurasidone 20 mg/day, max 40 mg/day. Avoid concurrent use of grapefruit products. Consider therapy modification

Lurbinectedin: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Lurbinectedin. Management: Avoid concomitant use of lurbinectedin and moderate CYP3A4 inhibitors when possible. If combined, consider a lurbinectedin dose reduction as clinically indicated. Consider therapy modification

Macitentan: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Macitentan. Monitor therapy

Manidipine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Manidipine. Monitor therapy

Meperidine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Meperidine. Monitor therapy

MethylPREDNISolone: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of MethylPREDNISolone. Monitor therapy

Mirodenafil: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Mirodenafil. Monitor therapy

Naldemedine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Naldemedine. Monitor therapy

Nalfurafine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Nalfurafine. Monitor therapy

Naloxegol: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Naloxegol. Management: The use of naloxegol and moderate CYP3A4 inhibitors should be avoided. If concurrent use is unavoidable, reduce naloxegol dose to 12.5 mg once daily and monitor for signs of opiate withdrawal (eg, hyperhidrosis, chills, diarrhea, anxiety, irritability). Consider therapy modification

Neratinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Neratinib. Monitor therapy

NiMODipine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of NiMODipine. Monitor therapy

Olaparib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Olaparib. Management: Avoid use of moderate CYP3A4 inhibitors with olaparib, if possible. If such concurrent use cannot be avoided, the dose of olaparib tablets should be reduced to 150 mg twice daily and the dose of olaparib capsules should be reduced to 200 mg twice daily. Consider therapy modification

Oliceridine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Oliceridine. Monitor therapy

OxyCODONE: CYP3A4 Inhibitors (Moderate) may enhance the adverse/toxic effect of OxyCODONE. CYP3A4 Inhibitors (Moderate) may increase the serum concentration of OxyCODONE. Serum concentrations of the active metabolite Oxymorphone may also be increased. Monitor therapy

PAZOPanib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of PAZOPanib. Monitor therapy

Pemigatinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Pemigatinib. Management: If combined use cannot be avoided, reduce the pemigatinib dose from 13.5 mg daily to 9 mg daily, or from 9 mg daily to 4.5 mg daily. Resume prior pemigatinib dose after stopping the moderate inhibitor once 3 half-lives of the inhibitor has passed. Consider therapy modification

Pexidartinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Pexidartinib. Management: Avoid use of pexidartinib with moderate CYP3A4 inhibitors if possible. If combined, the pexidartinib dose should be reduced. Decrease 800 mg or 600 mg daily doses to 200 mg twice daily. Decrease doses of 400 mg per day to 200 mg once daily. Consider therapy modification

Pimecrolimus: CYP3A4 Inhibitors (Moderate) may decrease the metabolism of Pimecrolimus. Monitor therapy

Pimozide: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Pimozide. Avoid combination

Propafenone: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Propafenone. Monitor therapy

Quinidine (Non-Therapeutic): CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Quinidine (Non-Therapeutic). Monitor therapy

Ranolazine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Ranolazine. Management: Limit the ranolazine dose to a maximum of 500 mg twice daily in patients concurrently receiving moderate CYP3A4 inhibitors. Monitor for increased ranolazine effects and toxicities during concomitant use. Consider therapy modification

Rimegepant: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Rimegepant. Management: Avoid a second dose of rimegepant within 48 hours when used concomitantly with moderate CYP3A4 inhibitors. Consider therapy modification

Rupatadine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Rupatadine. Monitor therapy

Ruxolitinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Ruxolitinib. Monitor therapy

Salmeterol: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Salmeterol. Monitor therapy

Sarilumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

SAXagliptin: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of SAXagliptin. Monitor therapy

Selpercatinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Selpercatinib. Management: Avoid combination if possible. If use is necessary, reduce selpercatinib dose as follows: from 120 mg twice/day to 80 mg twice/day, or from 160 mg twice/day to 120 mg twice/day. Consider therapy modification

Selumetinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Selumetinib. Management: Avoid concomitant use when possible. If combined, selumetinib dose reductions are recommended and vary based on body surface area and selumetinib dose. For details, see the full drug interaction monograph or selumetinib prescribing information. Consider therapy modification

Serotonergic Agents (High Risk): Antiemetics (5HT3 Antagonists) may enhance the serotonergic effect of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Monitor therapy

Sildenafil: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Sildenafil. Monitor therapy

Silodosin: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Silodosin. Monitor therapy

Siltuximab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Simeprevir: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Simeprevir. Avoid combination

Sirolimus: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Sirolimus. Management: Monitor for increased serum concentrations of sirolimus if combined with a moderate CYP3A4 inhibitor. Lower initial sirolimus doses or sirolimus dose reductions will likely be required. Consider therapy modification

Sonidegib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Sonidegib. Management: Avoid concomitant use of sonidegib and moderate CYP3A4 inhibitors when possible. When concomitant use cannot be avoided, limit CYP3A4 inhibitor use to less than 14 days and monitor for sonidegib toxicity (particularly musculoskeletal adverse reactions). Consider therapy modification

SUNItinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of SUNItinib. Monitor therapy

Suvorexant: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Suvorexant. Management: The recommended dose of suvorexant is 5 mg daily in patients receiving a moderate CYP3A4 inhibitor. The dose can be increased to 10 mg daily (maximum dose) if necessary for efficacy. Consider therapy modification

Tacrolimus (Systemic): CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Tacrolimus (Systemic). Monitor therapy

Tadalafil: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Tadalafil. Monitor therapy

Tamsulosin: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Tamsulosin. Monitor therapy

Tazemetostat: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Tazemetostat. Management: Avoid when possible. If combined, reduce tazemetostat dose from 800 mg twice daily to 400 mg twice daily, from 600 mg twice daily to 400 mg in AM and 200 mg in PM, or from 400 mg twice daily to 200 mg twice daily. Consider therapy modification

Telithromycin: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Telithromycin. Monitor therapy

Tetrahydrocannabinol: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Tetrahydrocannabinol. Monitor therapy

Tezacaftor and Ivacaftor: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Tezacaftor and Ivacaftor. Management: If combined with moderate CYP3A4 inhibitors, give tezacaftor/ivacaftor in the morning, every other day; give ivacaftor in the morning, every other day on alternate days. Tezacaftor/ivacaftor dose depends on age and weight; see full Lexi-Interact monograph Consider therapy modification

Ticagrelor: CYP3A4 Inhibitors (Moderate) may decrease serum concentrations of the active metabolite(s) of Ticagrelor. CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Ticagrelor. Monitor therapy

Tocilizumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Tofacitinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Tofacitinib. Monitor therapy

Tolterodine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Tolterodine. Monitor therapy

Tolvaptan: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Tolvaptan. Management: Avoid this combination with Samsca brand of tolvaptan. Reduce dose for Jynarque brand: 90 mg AM and 30 mg PM, reduce to 45 mg AM and 15 mg PM; 60 mg AM and 30 mg PM, reduce to 30 mg AM and 15 mg PM; 45 mg AM and 15 mg PM, reduce to 15 mg AM and PM. Consider therapy modification

Toremifene: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Toremifene. Monitor therapy

Trabectedin: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Trabectedin. Monitor therapy

TraMADol: Antiemetics (5HT3 Antagonists) may enhance the serotonergic effect of TraMADol. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Monitor therapy

Triazolam: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Triazolam. Management: Consider triazolam dose reduction in patients receiving concomitant moderate CYP3A4 inhibitors. Consider therapy modification

Ubrogepant: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Ubrogepant. Management: Use an initial ubrogepant dose of 50 mg and avoid a second dose for 24 hours when used with moderate CYP3A4 inhibitors. Consider therapy modification

Udenafil: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Udenafil. Monitor therapy

Ulipristal: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Ulipristal. Management: This is specific for when ulipristal is being used for signs/symptoms of uterine fibroids (Canadian indication). When ulipristal is used as an emergency contraceptive, patients receiving this combination should be monitored for ulipristal toxicity. Avoid combination

Valbenazine: CYP3A4 Inhibitors (Moderate) may increase serum concentrations of the active metabolite(s) of Valbenazine. CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Valbenazine. Monitor therapy

Vardenafil: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Vardenafil. Management: Limit Levitra (vardenafil) dose to a single 5 mg dose within a 24-hour period if combined with moderate CYP3A4 inhibitors. Avoid concomitant use of Staxyn (vardenafil) and moderate CYP3A4 inhibitors. Combined use is contraindicated outside of the US. Consider therapy modification

Vemurafenib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Vemurafenib. Monitor therapy

Venetoclax: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Venetoclax. Management: Reduce the venetoclax dose by at least 50% in patients requiring concomitant treatment with moderate CYP3A4 inhibitors. Resume the previous venetoclax dose 2 to 3 days after discontinuation of moderate CYP3A4 inhibitors. Consider therapy modification

Verapamil: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Verapamil. Monitor therapy

Vilazodone: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Vilazodone. Monitor therapy

VinBLAStine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of VinBLAStine. Monitor therapy

VinCRIStine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of VinCRIStine. Monitor therapy

VinCRIStine (Liposomal): CYP3A4 Inhibitors (Moderate) may increase the serum concentration of VinCRIStine (Liposomal). Monitor therapy

Vindesine: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Vindesine. Monitor therapy

Vorapaxar: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Vorapaxar. Monitor therapy

Zanubrutinib: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Zanubrutinib. Management: Decrease the zanubrutinib dose to 80 mg twice daily during coadministration with a moderate CYP3A4 inhibitor. Further dose adjustments may be required for zanubrutinib toxicities, refer to prescribing information for details. Consider therapy modification

Zopiclone: CYP3A4 Inhibitors (Moderate) may increase the serum concentration of Zopiclone. Monitor therapy

Fosnetupitant / palonosetron drug interactions (more detail)

Adverse Reactions

See Palonosetron monograph.

Fosnetupitant / palonosetron side effects (more detail)

Warnings/Precautions

Concerns related to adverse effects:

• Hypersensitivity: Hypersensitivity (including anaphylaxis) has been reported with palonosetron (a component of the product), with or without known hypersensitivity to other 5-HT3 receptor antagonists

• Serotonin syndrome: Serotonin syndrome has been reported with 5-HT3 receptor antagonists, predominantly when used in combination with other serotonergic agents (eg, SSRIs, SNRIs, MAOIs, mirtazapine, fentanyl, lithium, tramadol, methylene blue). Some of the cases have been fatal. The majority of serotonin syndrome reports with 5-HT3 receptor antagonists occurred in a postanesthesia setting or in an infusion center. Serotonin syndrome has also been reported following overdose of another 5-HT3 receptor antagonist. Monitor patients for signs of serotonin syndrome, including mental status changes (eg, agitation, hallucinations, delirium, coma); autonomic instability (eg, tachycardia, labile blood pressure, diaphoresis, dizziness, flushing, hyperthermia); neuromuscular changes (eg, tremor, rigidity, myoclonus, hyperreflexia, incoordination); gastrointestinal symptoms (eg, nausea, vomiting, diarrhea); and/or seizures. If serotonin syndrome occurs, discontinue 5-HT3 receptor antagonist treatment and begin supportive management.

Disease-related concerns:

• Hepatic impairment: Avoid use in severe hepatic impairment. Dosage adjustment not necessary in mild or moderate impairment.

• Renal impairment: Avoid use in severe renal impairment or end-stage renal disease (ESRD). Dosage adjustment not necessary in mild or moderate impairment.

Special populations:

• Elderly: Use caution when dosing elderly patients due to a higher frequency of decreased hepatic, renal, cardiac function, and concomitant disease or drug therapy.

Monitoring Parameters

Monitor for signs/symptoms of hypersensitivity and serotonin syndrome.

Pregnancy Considerations

Adverse events were observed in some animal reproduction studies using the components of this combination product.

Patient Education

What is this drug used for?

• It is used to prevent upset stomach and throwing up from chemo.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Constipation

• Headache

• Redness

• Loss of strength and energy

• Nausea

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Serotonin syndrome like dizziness, severe headache, agitation, sensing things that seem real but are not, fast heartbeat, abnormal heartbeat, flushing, tremors, sweating a lot, change in balance, severe nausea, or severe diarrhea

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine's uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer