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Quick facts
- How it is given
- intravenous
- Type
- human prescription drug
- Brand names
- FOCINVEZ
- RxNorm ID
- 2664065
We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.
What it is used to treat
in combination with other antiemetic agents, is indicated in adults and pediatric patients 6 months of age and older for the prevention of: acute and delayed nausea and vomiting associated with initial and repeat courses of highly emetogenic cancer chemotherapy (HEC) including high-dose cisplatin. delayed nausea and vomiting associated with initial and repeat courses of moderately emetogenic cancer chemotherapy (MEC). Limitations of Use FOCINVEZ has not been studied for the treatment of established nausea and vomiting. FOCINVEZ is a substance P/neurokinin-1 (NK 1 ) receptor antagonist, indicated in adults and pediatric patients 6 months of age and older, in combination with other antiemetic agents, for the prevention of (1) : acute and delayed nausea and vomiting associated with initial and repeat courses of highly emetogenic cancer chemotherapy (HEC) including high-dose cisplatin. delayed nausea and vomiting associated with initial and repeat courses of moderately emetogenic cancer chemotherapy (MEC). Limitations of Use (1) FOCINVEZ has not been studied for treatment of established nausea and vomiting.
About this medicine
(fosaprepitant injection) is a sterile, ready-to-use, clear and colorless solution formulation containing fosaprepitant dimeglumine, a prodrug of aprepitant, a substance P/neurokinin-1 (NK 1 ) receptor antagonist, an antiemetic agent, chemically described as 1-Deoxy-1-(methylamino)-D-glucitol[3-[[(2 R ,3S)-2-[(1 R )-1-[3,5bis(trifluoromethyl)phenyl]ethoxy]-3-(4-fluorophenyl)-4-morpholinyl]methyl]-2,5-dihydro-5-oxo-1 H -1,2,4triazol-1-yl]phosphonate (2:1) (salt). Its empirical formula is C 23 H 22 F 7 N 4 O 6 P ⋅ 2(C 7 H 17 NO 5 ) and its structural formula is: Fosaprepitant dimeglumine is a white to off-white amorphous powder with a molecular weight of 1004.83. It is freely soluble in water. Each 50 mL vial of FOCINVEZ for administration as an intravenous infusion contains 150 mg of fosaprepitant (equivalent to 245.3 mg of fosaprepitant dimeglumine) and the following inactive ingredients: Betadex sulfobutyl ether sodium (8 g), edetate disodium (5.4 mg), sodium hydroxide (for pH adjustment) in water for injection. structure
How it works
12.1 Mechanism of Action Fosaprepitant is a prodrug of aprepitant and accordingly, its antiemetic effects are attributable to aprepitant. Aprepitant is a selective high-affinity antagonist of human substance P/neurokinin 1 (NK 1 ) receptors. Aprepitant has little or no affinity for serotonin (5-HT 3 ), dopamine, and corticosteroid receptors, the targets of existing therapies for chemotherapy-induced nausea and vomiting (CINV). Aprepitant has been shown in animal models to inhibit emesis induced by cytotoxic chemotherapeutic agents, such as cisplatin, via central actions. Animal and human Positron Emission Tomography (PET) studies with aprepitant have shown that it crosses the blood brain barrier and occupies brain NK 1 receptors. Animal and human studies have shown that aprepitant augments the antiemetic activity of the 5-HT 3 -receptor antagonist ondansetron and the corticosteroid dexamethasone and inhibits both the acute and delayed phases of cisplatin-induced emesis.
Who should not take it
is contraindicated in patients: who are hypersensitive to any component of the product. Hypersensitivity reactions including anaphylactic reactions, flushing, erythema, and dyspnea have been reported [see Warnings and Precautions (5.2 ), and Adverse Reactions ( 6.2 )] . taking pimozide. Inhibition of CYP3A4 by aprepitant, the active moiety, could result in elevated plasma concentrations of this drug, which is a CYP3A4 substrate, potentially causing serious or life-threatening reactions, such as QT prolongation, a known adverse reaction of pimozide [see Warnings and Precautions ( 5.1 )] . Known hypersensitivity to any component of this drug. ( 4 , 5.2 ) Concurrent use with pimozide. ( 4 )
Warnings and cautions
CYP3A4 Interactions: Fosaprepitant is a weak inhibitor of CYP3A4, and aprepitant, the active moiety, is a substrate, inhibitor, and inducer of CYP3A4; see Full Prescribing Information for recommendations regarding contraindications, risk of adverse reactions, and dosage adjustment of FOCINVEZ and concomitant drugs. ( 4 , 5.1 , 7.1 , 7.2 ) Hypersensitivity Reactions (including anaphylaxis and anaphylactic shock) : May occur during or soon after infusion. If symptoms occur, discontinue the drug. Do not reinitiate FOCINVEZ if symptoms occur with previous use. ( 4 , 5.2 ) I nfusion Site Reactions (including thrombophlebitis, necrosis, and vasculitis) : Majority of reactions reported in patients receiving vesicant chemotherapy. Avoid infusion into small veins. Discontinue infusion and administer treatment if a severe reaction develops. ( 5.3 ) Warfarin (a CYP2C9 substrate): Risk of decreased INR of prothrombin time; monitor INR in 2–week period, particularly at 7 to 10 days, following initiation of FOCINVEZ. ( 5.4 , 7.1 ) Hormonal Contraceptives: Efficacy of contraceptives may be reduced during treatment and for 1 month following administration of the last dose of either fosaprepitant or oral aprepitant. Use effective alternative or back-up methods of contraception. ( 5.5 , 7.1 , 8.3 ) 5.1 Clinically Significant CYP3A4 Drug Interactions Fosaprepitant, a prodrug of aprepitant, is a weak inhibitor of CYP3A4, and aprepitant is a substrate, inhibitor, and inducer of CYP3A4. Use of FOCINVEZ with other drugs that are CYP3A4 substrates, may result in increased plasma concentration of the concomitant drug. Use of pimozide with FOCINVEZ is contraindicated due to the risk of significantly increased plasma concentrations of pimozide, potentially resulting in prolongation of the QT interval, a known adverse reaction of pimozide [see Contraindications (4) ] . Use of FOCINVEZ with strong or moderate CYP3A4 inhibitors (e.g., ketoconazole, diltiazem) may increase plasma concentrations of aprepitant and result in an increased risk of adverse reactions related to FOCINVEZ. […]
Reported side effects
The following clinically significant adverse reactions are described elsewhere in the labeling: Hypersensitivity Reactions [see Warnings and Precautions ( 5.2 )] Infusion Site Reactions [see Warnings and Precautions ( 5.3 )] Most common adverse reactions in adults (≥2%) are: fatigue, diarrhea, neutropenia, asthenia, anemia, peripheral neuropathy, leukopenia, dyspepsia, urinary tract infection, pain in extremity. ( 6.1 ) Adverse reactions in pediatric patients are similar to adults. To report SUSPECTED ADVERSE REACTIONS, contact Steriscience at 1-888-278-1784 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. The safety of FOCINVEZ has been established from adequate and well-controlled studies of another intravenous formulation of fosaprepitant [see Clinical Studies ( 14 )] . Below is a display of the adverse reactions of fosaprepitant in these studies. The overall safety of intravenous fosaprepitant was evaluated in approximately 1800 adult and pediatric patients. Adverse Reactions in Adults for the Prevention of Nausea and Vomiting Associated with MEC In an active-controlled clinical trial in patients receiving MEC, safety was evaluated in 504 patients receiving a single dose of intravenous fosaprepitant in combination with ondansetron and dexamethasone (intravenous fosaprepitant regimen) compared to 497 patients receiving ondansetron and dexamethasone alone (standard therapy). The most common adverse reactions are listed in Table 6. […]
Interactions with other medicines
See Full Prescribing Information for a list of clinically significant drug interactions. ( 4 , 5.1 , 5.4 , 5.5 , 7.1 , 7.2 ) Additional pediatric use information is approved for Merck Sharp & Dohme LLC’s EMEND (fosaprepitant) for injection. However, due to Merck Sharp & Dohme LLC’s marketing exclusivity rights, this drug product is not labeled with that information. 7.1 Effect of Fosaprepitant/Aprepitant on the Pharmacokinetics of Other Drugs When administered intravenously, fosaprepitant, a prodrug of aprepitant, is converted to aprepitant within 30 minutes. Therefore, drug interactions following administration of FOCINVEZ are likely to occur with drugs that interact with oral aprepitant. Fosaprepitant, given as a single 150-mg dose, is a weak inhibitor of CYP3A4, and the weak inhibition of CYP3A4 continues for 2 days after single dose administration. Single dose fosaprepitant does not induce CYP3A4. Aprepitant is a substrate, an inhibitor, and an inducer of CYP3A4. Aprepitant is also an inducer of CYP2C9 [see Clinical Pharmacology ( 12.3 )] . Some substrates of CYP3A4 are contraindicated with FOCINVEZ [see Contraindications ( 4 )] . Dosage adjustment of some CYP3A4 and CYP2C9 substrates may be warranted, as shown in Table 7. Table 7 Effects of Fosaprepitant/Aprepitant on the Pharmacokinetics of Other Drugs CYP3A4 Substrates Pimozide Clinical Impact Increased pimozide exposure Intervention FOCINVEZ is contraindicated [see Contraindications ( 4 )] . Benzodiazepines Clinical Impact Increased exposure to midazolam or other benzodiazepines metabolized via CYP3A4 (alprazolam, triazolam) may increase the risk of adverse reactions [see Clinical Pharmacology ( 12.3 )] . Intervention Monitor for benzodiazepine-related adverse reactions. Dexamethasone Clinical Impact Increased dexamethasone exposure [see Clinical Pharmacology ( 12.3 )] . Intervention Reduce the dose of oral dexamethasone by approximately 50% [see Dosage and Administration ( 2.1 )]. Methylprednisolone Clinical Impact Increased methylprednisolone exposure [see Clinical Pharmacology ( 12.3 )]. […]
Use in specific groups
8.1 Pregnancy Risk Summary There are insufficient data on use of fosaprepitant in pregnant women to identify a drug associated risk of major birth defects, miscarriage or other adverse maternal or fetal outcomes. In animal reproduction studies, no adverse developmental effects were observed in rats or rabbits exposed during the period of organogenesis to systemic drug levels (AUC) approximately equivalent to the exposure at the recommended human dose (RHD) of 150 mg (see Data ). The background risk of major birth defects and miscarriage for the indicated populations is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively. Data Animal Data In embryofetal development studies in rats and rabbits, aprepitant was administered during the period of organogenesis at oral doses up to 1000 mg/kg twice daily (rats) and up to the maximum tolerated dose of 25 mg/kg/day (rabbits). No embryofetal lethality or malformations were observed at any dose level in either species. The exposures (AUC) in pregnant rats at 1000 mg/kg twice daily and in pregnant rabbits at 25 mg/kg/day were approximately equivalent to the exposure at the RHD of 150 mg. Aprepitant crosses the placenta in rats and rabbits. 8.2 Lactation Risk Summary There are no data on the presence of aprepitant in human milk, the effects on the breastfed infant, or the effects on milk production. Aprepitant is present in rat milk. When a drug is present in animal milk, it is likely that the drug will be present in human milk. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for FOCINVEZ and any potential adverse effects on the breastfed infant from FOCINVEZ or from the underlying maternal condition. 8.3 Females and Males of Reproductive Potential Contraception Upon administration of FOCINVEZ, the efficacy of hormonal contraceptives may be reduced. […]
If too much is taken
There is no specific information on the treatment of overdosage with fosaprepitant or aprepitant. In the event of overdose, FOCINVEZ should be discontinued and general supportive treatment and monitoring should be provided. Aprepitant is not removed by hemodialysis.
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Tell your pharmacist or doctor about every medicine you take — including ones bought without a prescription, herbal products and supplements. Interactions are one of the most common avoidable causes of harm from medicines, and a pharmacist can check your full list in a couple of minutes.
This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 30 March 2026. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.