FOLFIRI and Altuzan (Bevacizumab) Treatment Regimen for Colon Cancer
Reading tools
In this article
FOLFIRI + Bevacizumabcombines irinotecan/5-FU/folinic acid chemotherapy in metastatic colorectal cancer (mCRC) with the anti-VEGF antibody Bevacizumab . Multicenter trials have demonstrated benefits in progression-free survival (PFS) and overall survival (OS) for this 1st-line/subsequent-line strategy. The goal is simultaneous suppression of tumor proliferation and angiogenesis.
What Is FOLFIRI + Bevacizumab, and How Does It Work?
- Irinotecan: Converted in the liver by CYP3A4 into the active metabolite SN-38; inhibits topoisomerase-I, causing single-strand DNA breaks and stopping the cell cycle.
- 5-Fluorouracil: Inhibits thymidylate synthase to block DNA synthesis and disrupts RNA synthesis.
- Folinic Acid: Stabilizes 5-FU binding to thymidylate synthase, increasing 5-FU efficacy.
- Bevacizumab: Neutralizes Vascular Endothelial Growth Factor A (VEGF-A), inhibiting new tumor vessels (neoangiogenesis), reducing vascular permeability, and potentially increasing chemotherapy penetration.
Treatment Goals
- Reduce tumor burden and extend life (OS, PFS benefit).
- Control symptoms (pain, bleeding, obstruction) and improve performance status.
- In suitable cases, increase the chance of conversion/resectability (particularly limited liver metastases).
- For long-term control, maintenance (5-FU±Bevacizumab) and appropriate sequencing strategies.
Indication and Guideline Position
- mCRC 1st line: An anti-VEGF-based combination selected according to clinical and molecular context, regardless of RAS/BRAF status. (Compare with anti-EGFR therapy in left-sided RAS-wild-type disease; anti-VEGF is often more rational in right-sided/RAS-mutated cases.) Strongly recommended as 1st-line metastatic colorectal cancer treatment.
- Later lines: FOLFIRI-bev may be positioned within the sequence according to previous regimens and toxicity.
- Guidelines: NCCN (v.2025) and ESMO (2022) recommend it with strong evidence.
SGK Reimbursement (Türkiye)
- Colorectal cancer is an indication in which Bevacizumab and FOLFIRI components are reimbursed by SGK.
- Reimbursement requires meeting conditions regarding the report/indication wording, treatment line, ECOG, and metastatic disease for eligibility.
- Bevacizumab is marketed as: Altuzan, Zibarev, Mvası, Bevax
Dose and Administration Order (14 days; 1 cycle = 14 days)
- Bevacizumab: 5 mg/kg intravenous infusion, generally before chemotherapy (initial administration 90 minutes, subsequent infusions 30–60 minutes).
- Irinotecan: 180 mg/m² intravenous infusion over 90 minutes (day 1).
- Leucovorin: 400 mg/m² intravenous infusion over 2 hours (day 1, may be coadministered through a Y-set).
- 5-Fluorouracil (bolus): 400 mg/m² intravenously (day 1).
- 5-Fluorouracil (infusion): 2400–3000 mg/m² through a portable pump over 46 hours.
Premedication & Support: Moderately emetogenic → 5-HT3 antagonist + dexamethasone ± NK1. Acute cholinergic syndrome (irinotecan): keep atropine 0.25–1 mg SC/IV available. Delayed diarrhea requires a high-dose loperamide protocol (initially 4 mg, then 2 mg every 2 hours; until symptom-free for 12 hours).
Pretreatment Checks and Monitoring Between Visits
- Laboratory: Complete blood count, creatinine/eGFR, AST/ALT/ALP/bilirubin, electrolytes. Urine protein (dipstick) ± 24-hour protein (for Bev).
- Vitals: Blood pressure (before Bev), weight, performance (ECOG).
- UGT1A1 assessment: With prior severe 5-FU/irinotecan toxicity or jaundice/hyperbilirubinemia, UGT1A1*28 testing may be considered; *28/*28 cases may start lower (e.g., 120–150 mg/m²).
- Imaging: Baseline CT/MRI; every 8–12 weeks for response.
- Monitoring: Blood count + biochemistry + blood pressure before each cycle; repeat proteinuria testing every 1–2 cycles.
Administration Precautions
- Irinotecan-related acute cholinergic symptoms (abdominal cramps, sweating, hypersalivation): during infusion, rapid control with atropine.
- Delayed diarrhea: Early, aggressive loperamide; fluid support for dehydration/electrolyte loss.
- Pump management: 46-hour 5-FU infusion; education on line care, flow checks, blockage, and skin irritation.
- Hypertension and proteinuria: BP <140/90 before Bevacizumab; periodic 24-hour measurement with proteinuria.
- Surgical planning: Between Bevacizumab and invasive procedures, allow ≥6 weeks as an interval.
Drug Interactions
- Irinotecan: CYP3A4 inhibitors (e.g., azole antifungals, macrolides) may increase toxicity. CYP3A4 inducers (e.g., rifampicin, phenytoin) may reduce efficacy.
- 5-Fluorouracil: May increase INR with warfarin. Concurrent Brivudine or Sorivudine risks fatal toxicity (contraindicated).
- Bevacizumab: Bleeding risk may increase with anticoagulants and antiplatelet agents.
Special Clinical Considerations
- Hyperbilirubinemia/cholestasis: Bilirubin 1.5–2× ULN → reduce irinotecan by 20–25%; >2× ULN → irinotecan not recommended/extreme caution.
- Older/frail patients: Consider lower-dose irinotecan or omitting the 5-FU bolus.
- Thromboembolic history: Balance Bevacizumab bleeding/thrombosis risks; individualize anticoagulation.
- Pregnancy: Bevacizumab is contraindicated; effective contraception during reproductive years.
Approach to Dose Modification
| Condition | Recommendation | Note |
|---|---|---|
| G3–4 neutropenia or febrile neutropenia | Delay cycle; irinotecan reduced by 20–25%; 5-FU bolus omit/reduce; assess G-CSF prophylaxis | Resume when ANC ≥1500/mm³ and clinically stable |
| G≥3 diarrhea (delayed) | Delay cycle; hydration + loperamide ± octreotide; after improvement, irinotecan reduced by 20% and/or omit 5-FU bolus | Monitor electrolytes; further reduction if recurrence |
| Severe mucositis/dermatitis (5-FU) | Temporarily withhold; after improvement, 5-FU reduced by 20–25% | Oral care protocol |
| Bevacizumab G≥3 hypertension | Delay until controlled; optimize antihypertensives | Consider discontinuation if refractory |
| Proteinuria ≥2 g/24 h | Bevacizumab withhold; reassess after improvement | Nephrology opinion |
| GI perforation/serious bleeding/PRES | Bevacizumab permanently discontinue | Emergency management |
Exact dose changes should be individualized according to institutional protocols and patient characteristics.
Side-Effect Frequency and Practical Management Tips
>20% Very common 10–20% Common 1–10% Less common <1% Rare/serious
Irinotecan
| Frequency | Adverse effect | Tip |
|---|---|---|
| >20% | Delayed diarrhea | High-dose loperamide algorithm; hydration; start early |
| >20% | Neutropenia | Close CBC monitoring; G-CSF prophylaxis in high-risk cases |
| 10–20% | Acute cholinergic syndrome | Atropine 0.25–1 mg SC/IV during infusion |
| 1–10% | Nausea-vomiting, alopecia, transaminases ↑ | Antiemetics + support |
| <1% | Interstitial lung disease | CT and treatment interruption for dyspnea/cough |
5-Fluorouracil
| Frequency | Adverse effect | Tip |
|---|---|---|
| >20% | Mucositis, hand–foot syndrome | Oral care; urea–salicylic creams |
| 10–20% | Diarrhea/nausea-vomiting | Early symptom management |
| 1–10% | Myelosuppression, rash | Review doses |
| <1% | Cardiotoxicity (ischemic) | Stop immediately for chest pain + cardiology assessment |
Bevacizumab
| Frequency | Adverse effect | Tip |
|---|---|---|
| >20% | Hypertension, epistaxis (mild) | BP control; local measures |
| 10–20% | Proteinuria, delayed wound healing | Dipstick/24h; ≥6-week break before surgery |
| 1–10% | Thromboembolism | Balance risk/prophylaxis |
| <1% | GI perforation, serious bleeding, PRES | Urgent assessment; permanent discontinuation |
Frequencies may vary by study and combination.
FOLFIRI + Bevacizumabis a strong option in mCRC with appropriate selection and proactive toxicity management. Early diarrhea/neutropenia control and management of Bevacizumab-specific vascular risks, alongside long-term maintenance (5-FU±Bev) and appropriate sequencing , improve treatment success.
References
1) Hurwitz H, et al. Bevacizumab with chemotherapy in mCRC. N Engl J Med. 2004.
2) Tournigand C, et al. FOLFIRI vs FOLFOX in mCRC sequencing. J Clin Oncol. 2004 & updates.
3) NCCN Clinical Practice Guidelines in Oncology: Colon/Rectal Cancer, v.2025.
4) ESMO Guidelines: Metastatic Colorectal Cancer. Ann Oncol. 2022 and updates.
5) Grothey A, et al. Maintenance strategies with FP±Bevacizumab in mCRC. J Clin Oncol. 2012 & updates.
Was this article helpful?
Your feedback helps us improve our content.
Reader comments
Share your comment
Your name and comment are published only after administrator approval. Your email address is never shown to visitors.
Be the first to comment.