Indication

Sunitinib (Sunitix) 25 mg is prescribed for the treatment of several cancers, including advanced renal cell carcinoma (RCC), gastrointestinal stromal tumors (GIST), and pancreatic neuroendocrine tumors (pNET).

Pharmacology

Sunitinib effectively inhibits multiple receptor tyrosine kinases (RTKs), such as vascular endothelial growth factor receptors (VEGFRs), platelet-derived growth factor receptors (PDGFRs), and stem cell factor receptor (KIT). This inhibition impedes tumor growth, angiogenesis, and metastasis, contributing to its anticancer properties.

Dosage and Administration

The recommended dose of Sunitinib (Sunitix) 25 mg is tailored based on the cancer type and individual patient response. Typically, it is taken orally once daily, either continuously or in cycles of four weeks on treatment followed by two weeks off treatment. The capsules should be swallowed whole with water, preferably at the same time each day, with or without food.

Interaction

Sunitinib may interact with various medications, including potent CYP3A4 inhibitors and inducers, as well as drugs affecting gastric pH. Co-administration of these agents may influence sunitinib’s plasma levels, potentially impacting its effectiveness or causing adverse effects. Therefore, a thorough review of the patient’s medication history is essential before initiating sunitinib therapy.

Side Effects

Common side effects associated with sunitinib treatment include fatigue, diarrhea, nausea, vomiting, hypertension, hand-foot syndrome (palmar-plantar erythrodysesthesia), stomatitis, and skin discoloration. Additionally, patients may experience hematological issues such as neutropenia, thrombocytopenia, and anemia.

Precautions and Warnings

Close monitoring of blood pressure, liver function, thyroid function, and cardiac function is necessary during sunitinib therapy. Patients should promptly report any new or worsening symptoms, including bleeding, signs of infection, or cardiovascular problems. Caution is advised when administering sunitinib to patients with pre-existing heart conditions or impaired liver or kidney function.

Overdose Effects

In cases of overdose, supportive care should be administered, and symptomatic treatment initiated as required. There is no specific antidote for sunitinib overdose, so patients should be carefully monitored for adverse reactions, and management should be individualized to address their symptoms accordingly.