FDA Approves Revisions to ERBITUX Labeling, Recommends K-ras Testing in Colorectal Cancer Patients
The US Food and Drug Administration (FDA) has approved revisions to the prescribing information for ERBITUX (cetuximab), a medication used to treat certain types of colorectal cancer. The revisions include a modification to the indication statement, which now includes a warning that retrospective subset analyses of metastatic or advanced colorectal cancer trials have not shown a treatment benefit for ERBITUX in patients whose tumors have K-ras mutations in codon 12 or 13. The FDA recommends that all patients with metastatic colorectal cancer be tested for K-ras gene mutations prior to treatment with an anti-EGFR monoclonal antibody therapy.
Key Takeaways:
- The FDA has approved revisions to the prescribing information for ERBITUX, including a modification to the indication statement that warns against the use of ERBITUX in patients with K-ras mutations in codon 12 or 13.
- Retrospective subset analyses of metastatic or advanced colorectal cancer trials have not shown a treatment benefit for ERBITUX in patients with K-ras mutations in codon 12 or 13.
- The FDA recommends that all patients with metastatic colorectal cancer be tested for K-ras gene mutations prior to treatment with an anti-EGFR monoclonal antibody therapy.
- An estimated 40% of patients with metastatic colorectal cancer have K-ras mutations, while the majority (approximately 60%) have a wild-type K-ras gene.
- Signal transduction through the EGFR results in activation of wild-type K-ras protein, while mutant K-ras protein is continuously active and appears independent of EGFR regulation.
- ERBITUX has been approved by the FDA for the treatment of metastatic colorectal cancer as a single agent and in combination with irinotecan or oxaliplatin.
Statistics:
- 40% of patients with metastatic colorectal cancer have K-ras mutations.
- 60% of patients with metastatic colorectal cancer have a wild-type K-ras gene.
- 90% of severe infusion reactions associated with ERBITUX occurred during the first infusion, despite premedication with antihistamines.
- 55% (199/365) of patients receiving ERBITUX had hypomagnesemia, with 6-17% experiencing severe (NCI CTC grades 3 & 4) cases.
- 88% of 1373 patients receiving ERBITUX in clinical trials developed acneform rash.
Sources:
- FDA news release, "FDA Approves Revisions to ERBITUX Labeling, Recommends K-ras Testing in Colorectal Cancer Patients"
- ImClone Systems press release, "ImClone Systems, Bristol-Myers Squibb and Lilly Recommend K-ras Testing in Colorectal Cancer Patients"
- ERBITUX Prescribing Information, "BOXED WARNINGS, INFUSION REACTIONS, PULMONARY TOXICITY, DERMATOLOGIC TOXICITIES, ELECTROLYTE DEPLETION, PREGNANCY, ADVERSE EVENTS"
- Bristol-Myers Squibb website, "About ERBITUX"
- Lilly website, "About ImClone Systems"
- Bristol-Myers Squibb website, "About Bristol-Myers Squibb"