API Rolapitant

Rolapitant More Info

Rolapitant is a potent, long-acting, and highly selective neurokinin-1 (NK1) receptor antagonist used primarily for the prevention of chemotherapy-induced nausea and vomiting (CINV). It is approved for clinical use in multiple regions including the United States, the European Union, and Japan.

Mechanism of Action

Rolapitant exerts its antiemetic effect by competitively blocking the binding of substance P—a key neurotransmitter involved in mediating nausea and vomiting signals—to NK1 receptors in the central nervous system (CNS), particularly in the vomiting center of the medulla oblongata and the chemoreceptor trigger zone (CTZ). Unlike some other antiemetics, its high selectivity for NK1 receptors minimizes off-target effects on other receptor classes (e.g., serotonin 5-HT3 or dopamine D2 receptors).

Clinical Applications

Prevention of CINV

Rolapitant is indicated for use in adults to prevent acute and delayed nausea and vomiting associated with initial and repeat courses of highly emetogenic chemotherapy (HEC) or moderately emetogenic chemotherapy (MEC). It is typically administered as part of a combination antiemetic regimen, often alongside a 5-HT3 receptor antagonist and dexamethasone.

Pharmacokinetic Characteristics

It has an exceptionally long elimination half-life of approximately 180 hours (7.5 days), allowing for a single oral dose per chemotherapy cycle.

The drug is well-absorbed after oral administration, with peak plasma concentrations reached within 4 hours. It is extensively metabolized by the cytochrome P450 3A4 (CYP3A4) enzyme system.

Dosage and Administration

The recommended adult dose is 180 mg taken orally, once within 2 hours before the start of chemotherapy. No dose adjustment is needed for mild to moderate hepatic or renal impairment.

Rolapitant is available as film-coated tablets for oral use.

Safety Profile

Rolapitant is generally well-tolerated. The most common adverse reactions reported in clinical trials include:

Fatigue

Constipation

Headache

Dyspepsia

Serious adverse events are rare. It is contraindicated in patients with a known hypersensitivity to rolapitant or any of the excipients in the formulation. Drug interactions should be monitored, especially with strong CYP3A4 inhibitors or inducers, as they may alter rolapitant plasma concentrations.