Netupitant/Palonosetron — Drug Monograph

Brand names: Akynzeo

Drug class: Supportive Care Agent

Mechanism of Action

Fixed-dose combination of netupitant (300 mg), a selective NK1 receptor antagonist, and palonosetron (0.5 mg PO or 0.25 mg IV), a second-generation 5-HT3 receptor antagonist. Provides simultaneous blockade of both serotonin (5-HT3) and substance P (NK1) pathways. Single-capsule convenience covers both acute and delayed phases of CINV in a once-per-cycle dose.

FDA Indications

• Prevention of acute and delayed nausea and vomiting associated with initial and repeat courses of highly emetogenic chemotherapy (oral capsule), in combination with dexamethasone
• Prevention of acute and delayed nausea and vomiting associated with initial and repeat courses of moderately emetogenic chemotherapy (oral capsule)
• IV formulation (fosnetupitant/palonosetron — Akynzeo IV): HEC and MEC prevention

Common Side Effects

• Headache
• Fatigue/asthenia
• Constipation
• Erythema (more common with IV formulation)
• Hiccups

Clinical Pearl

Akynzeo is the only single-capsule combination that provides both NK1 and 5-HT3 blockade in one dose. NCCN lists it as a Category 1 preferred option for HEC prophylaxis. The oral formulation contains a higher palonosetron dose (0.5 mg) than standard IV palonosetron (0.25 mg), which provides slightly extended coverage. NCCN/ASCO prefer Akynzeo for highly emetogenic regimens when simplicity and patient adherence are priorities — one pill replaces a 3-drug, 3-day antiemetic schedule.

Related Therapies & Mechanisms

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