Axitinib

Axitinib is an oral small-molecule tyrosine kinase inhibitor used in cancer therapy. It selectively targets vascular endothelial growth factor receptors 1, 2, and 3 (VEGFR-1, VEGFR-2, VEGFR-3) to disrupt tumor blood vessel formation and slow tumor growth.

Mechanism of action: Axitinib binds to the ATP-binding sites of VEGFRs, inhibiting signaling pathways that promote angiogenesis. By reducing vascular supply to tumors, it can help impede progression in certain cancers.

Indications and status: The drug is approved for metastatic renal cell carcinoma after failure of one prior systemic therapy. It is marketed under the brand name Inlyta and has received regulatory authorization in several regions, including the United States and the European Union.

Dosing and administration: The recommended starting dose is 5 mg taken twice daily. Dose titration may be considered at two-week intervals in 2 mg increments, up to a maximum of 15 mg twice daily, based on tolerability and adverse effects.

Pharmacokinetics and interactions: Axitinib is administered orally and is primarily metabolized by hepatic cytochrome P450 3A4. It has a relatively short half-life, and exposure can be affected by concomitant strong CYP3A4 inhibitors or inducers. Clinicians commonly adjust or hold therapy when such drugs are used.

Adverse effects and safety: Hypertension is among the most frequent and clinically important adverse effects. Other common events include diarrhea, fatigue, nausea, decreased appetite, vomiting, dysphonia, and hand-foot syndrome. Serious risks include thromboembolic events, hemorrhage, wound healing impairment, and liver enzyme elevations; ongoing monitoring and dose adjustments are recommended.

Regulatory and notes: As a VEGF-targeted agent, axitinib requires careful patient selection, monitoring of blood pressure and organ function, and awareness of drug interactions to manage safety and efficacy.