Aprepitant

What it is and how it works

Mechanism of Action 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.

Mechanism class: Neurokinin 1 Antagonists · Cytochrome P450 3A4 Inhibitors · Cytochrome P450 2C9 Inducers

Indications

® for oral suspension, in combination with other antiemetic agents, is indicated in 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. nausea and vomiting associated with initial and repeat courses of moderately emetogenic cancer chemotherapy (MEC). EMEND ® capsules, in combination with other antiemetic agents, is indicated in patients 12 years 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. nausea and vomiting associated with initial and repeat courses of moderately emetogenic cancer chemotherapy (MEC). EMEND ® is a substance P/neurokinin 1 (NK 1 ) receptor antagonist.

Dosage and administration (summary)

Recommended Dosage EMEND capsules in adults and pediatric patients 12 years of age and older: is 125 mg on Day 1 and 80 mg on Days 2 and 3. EMEND for oral suspension in pediatric patients 6 months to less than 12 years of age or pediatric and adult patients unable to swallow capsules: see dosing recommendations in Table 3 in the Full Prescribing Information. Administer EMEND 1 hour prior to chemotherapy on Days 1, 2, and 3. If no chemotherapy is given on Days 2 and 3, administer EMEND in morning. See Full Prescribing Information for recommended dosages of concomitant dexamethasone and 5-HT 3 antagonist for HEC and MEC.

Contraindications

is contraindicated in patients: who are hypersensitive to any component of the product. Hypersensitivity reactions including anaphylactic reactions have been reported . taking pimozide. Inhibition of CYP3A4 by aprepitant 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 . Known hypersensitivity to any component of this drug.

Warnings and precautions

CYP3A4 Interactions : Aprepitant is a substrate, weak-to-moderate inhibitor and inducer of CYP3A4; See Full Prescribing Information for recommendations regarding contraindications, risk of adverse reactions, and dosage adjustments of EMEND and concomitant drugs. ( 4 , 5.1 , 7.1 , 7.2 ) 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 EMEND.

Pregnancy

Pregnancy Risk Summary There are insufficient data on use of EMEND in pregnant women to inform a drug associated risk. 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 1.5 times the adult human exposure at the 125-…

Storage and supply

Storage and Handling Capsules Store at 20-25°C (68-77°F) . For Oral Suspension Store unopened pouch at 20-25°C (68-77°F); excursions permitted between 15-30°C (between 59-86°F). Store in the original container. Do not open pouch until ready for use.

Source: Aprepitant (Emend) — US FDA prescribing information, 2024-07-05, DailyMed. Summarised and shortened; the full label governs. Iranian registration, indications and labelling may differ.