Irinotecan Kabi (Irinotecan Hydrochloride Trihydrate)

• Irinotecan Kabi is a Topoisomerase I inhibitor used primarily in colorectal cancer therapy.
• Metastatic colorectal cancer: improves overall survival when combined with fluoropyrimidine‑based chemotherapy.
• Small cell lung cancer (second‑line): provides tumor control after failure of first‑line regimens.
• Advanced pancreatic cancer (clinical trials): investigated as part of combination protocols to enhance response rates.

• Irinotecan is converted intracellularly to SN‑38, a potent inhibitor of topoisomerase I. By stabilising the enzyme‑DNA cleavable complex, it prevents relaxation of super‑coiled DNA, thereby blocking DNA replication and transcription in rapidly dividing cancer cells and leading to cell death.

Irinotecan Kabi is associated with a range of adverse reactions.

Common Side Effects

• Nausea and vomiting: frequent gastrointestinal upset during and after infusion.
• Diarrhea: may be severe and require antidiarrheal therapy.
• Neutropenia: reduced white‑blood‑cell count increasing infection risk.
• Fatigue: generalised tiredness often reported by patients.

Serious or Rare Side Effects

• Febrile neutropenia: fever with low neutrophil count, a medical emergency.
• Severe colitis: intense inflammation of the colon leading to dehydration.
• Hypersensitivity reactions: rash, bronchospasm, or anaphylaxis during infusion.
• Hepatic toxicity: elevated liver enzymes indicating liver injury.
• Pulmonary toxicity: interstitial pneumonitis or fibrosis in rare cases.

• Prior to initiating Irinotecan therapy, several safety considerations are recommended.
• Dose adjustment in hepatic impairment: reduce dose based on liver function tests.
• Monitor blood counts regularly: weekly complete blood count during treatment cycles.
• Assess renal function: evaluate creatinine clearance before each dose.
• Avoid in patients with known hypersensitivity to irinotecan or formulation excipients.
• Pregnancy and breastfeeding: safety not established; use only if benefits outweigh risks.
• Store at 2‑8 °C: keep refrigerated, protect from light, do not freeze or shake.

Irinotecan may interact with other medicines, requiring careful management.

Major Interactions (Avoid)

• Strong CYP3A4 inducers (e.g., rifampin): markedly reduce irinotecan exposure.
• UGT1A1 inhibitors (e.g., atazanavir): increase SN‑38 levels and toxicity.
• Concurrent myelosuppressive agents: amplify risk of severe bone‑marrow suppression.

Moderate Interactions (Monitor Closely)

• Anticholinergic drugs: may worsen constipation associated with irinotecan.
• Warfarin: monitor INR as irinotecan can affect anticoagulant control.
• Fluoropyrimidines (e.g., 5‑FU): increase gastrointestinal toxicity when used together.