Irinotecan Hikma (Irinotecan Hydrochloride Trihydrate)

Irinotecan Hikma is used in oncology to target rapidly dividing cancer cells in several solid‑tumour indications.

• Metastatic colorectal cancer: improves overall survival when combined with fluoropyrimidine‑based regimens.
• Advanced gastric cancer: contributes to tumour response as part of multi‑agent chemotherapy.
• Advanced pancreatic cancer: used in combination protocols to enhance disease control.
• Non‑small cell lung cancer (advanced): added to standard regimens to increase response rates.

• Irinotecan is a pro‑drug that is converted intracellularly to the active metabolite SN‑38. SN‑38 binds to the DNA‑topoisomerase I complex, stabilising it and preventing religation of single‑strand DNA breaks during replication and transcription. This inhibition leads to accumulation of DNA damage, ultimately triggering apoptosis in rapidly proliferating tumor cells.

Irinotecan may cause a range of adverse reactions, which are grouped by frequency and severity.

Common Side Effects

• Neutropenia: reduced white blood cell count, increasing infection risk.
• Diarrhea: often mild to moderate, may require antidiarrheal therapy.
• Nausea and vomiting: typical chemotherapy‑related symptoms.
• Alopecia: temporary hair loss.
• Fatigue: generalized tiredness during treatment.
• Anemia: decreased red blood cell count.

Serious or Rare Side Effects

• Febrile neutropenia: fever with low neutrophils, a medical emergency.
• Severe colitis or watery diarrhea leading to dehydration.
• Hepatic dysfunction: elevated liver enzymes or bilirubin.
• Allergic reactions: rash, urticaria, or anaphylaxis.
• Severe abdominal pain or intestinal perforation.
• Thromboembolic events: blood clots in veins or arteries.

Before initiating therapy, clinicians should assess patient-specific risk factors and monitor for toxicity.

• Hematologic monitoring: perform regular complete blood counts to detect neutropenia.
• Hepatic function: evaluate liver enzymes and bilirubin prior to each cycle.
• Bowel assessment: screen for pre‑existing gastrointestinal disorders that could worsen with irinotecan.
• Concomitant myelosuppressants: avoid or adjust doses when used with other bone‑marrow‑suppressing agents.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze or shake.

Irinotecan interacts with several drug classes that can alter its efficacy or safety.

Major Interactions (Avoid)

• Strong CYP3A4 inducers (e.g., rifampin, carbamazepine): may reduce SN‑38 exposure.
• UGT1A1 inhibitors (e.g., atazanavir, indinavir): increase SN‑38 levels and risk of severe neutropenia.
• Concurrent high‑dose myelosuppressive chemotherapy: can exacerbate bone‑marrow toxicity.

Moderate Interactions (Monitor Closely)

• Moderate CYP3A4 inhibitors (e.g., erythromycin, fluconazole): may modestly raise irinotecan concentrations.
• Anticoagulants (e.g., warfarin): monitor INR as hepatic effects can alter metabolism.
• Antacids containing magnesium or aluminum: may affect absorption of oral formulations (not applicable to IV but noted for completeness).