Klertis (Sunitinib)

Klertis (sunitinib) acts on multiple receptor tyrosine kinases involved in tumor growth and angiogenesis, making it useful in several solid‑tumor indications.

• Renal cell carcinoma: slows disease progression and may extend survival in adults with advanced disease.
• Gastrointestinal stromal tumor: inhibits tumor growth in patients with unresectable or metastatic disease.
• Advanced renal cell carcinoma: provides disease control when prior therapies have failed.

• Sunitinib inhibits a spectrum of receptor tyrosine kinases, including VEGFR‑1/2/3, PDGFR‑α/β, KIT, FLT3 and CSF‑1R. By blocking these pathways it reduces angiogenesis, tumor cell proliferation and survival, leading to anti‑tumor activity in cancers that depend on these signaling cascades.

Sunitinib is associated with a range of adverse reactions that vary in frequency and severity.

Common Side Effects

• Fatigue: persistent tiredness affecting daily activities.
• Nausea and vomiting: gastrointestinal upset often occurring early in therapy.
• Diarrhea: loose stools that may require supportive care.
• Hypertension: elevated blood pressure needing monitoring.
• Hand‑foot syndrome: redness and swelling of palms and soles.
• Stomatitis: inflammation of the mouth lining.

Serious or Rare Side Effects

• Cardiac dysfunction: reduced left‑ventricular ejection fraction.
• Neutropenia: low neutrophil count increasing infection risk.
• Hepatotoxicity: elevated liver enzymes indicating liver injury.
• Thromboembolic events: blood clots in veins or arteries.
• Severe skin reactions: Stevens‑Johnson syndrome or toxic epidermal necrolysis.
• Pulmonary hemorrhage: bleeding within the lungs.

Before initiating therapy, clinicians should assess baseline organ function and comorbidities.

• Blood pressure monitoring: check and control hypertension throughout treatment.
• Liver function tests: perform baseline and periodic assessments.
• Cardiac evaluation: obtain baseline ECG or echocardiogram in at-risk patients.
• Hematologic monitoring: regular complete blood counts to detect cytopenias.
• Store at ambient temperature: keep below 25 °C, retain in original packaging, protect from moisture and direct sunlight.

Sunitinib may interact with other medicines that affect its metabolism or increase toxicity.

Major Interactions (Avoid)

• Strong CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin): may raise sunitinib exposure.
• Strong CYP3A4 inducers (e.g., rifampin, carbamazepine): may reduce efficacy.
• QT‑prolonging agents (e.g., quinidine, amiodarone): increase risk of cardiac arrhythmias.

Moderate Interactions (Monitor Closely)

• Anticoagulants (e.g., warfarin): heightened bleeding risk.
• Antihypertensives (e.g., ACE inhibitors): may require dose adjustments.
• CYP2C9 substrates (e.g., phenytoin): possible altered plasma levels.
• CYP2C19 inhibitors (e.g., fluoxetine): modest increase in exposure.
• St. John's wort: may lower drug concentrations.