FDA Approves Labeling Revisions for Erbitux Cetuximab in Metastatic Colorectal Cancer

Strategic Insights -

The US Food and Drug Administration (FDA) has approved revisions to the prescribing information for Erbitux (cetuximab) concerning the treatment of patients with epidermal growth factor receptor (EGFR)-expressing metastatic colorectal cancer (mCRC). The revisions include a modification to the indication, which now includes a statement that retrospective subset analyses of metastatic or advanced colorectal cancer trials have not shown a treatment benefit for Erbitux in patients whose tumors had K-ras mutations in codon 12 or 13. The labeling update also includes revisions concerning the use of Erbitux in colorectal cancer tumors with K-ras mutations in the clinical studies and clinical pharmacology sections of the product's prescribing information.

Key Takeaways:

  • The FDA has approved revisions to the prescribing information for Erbitux (cetuximab) concerning the treatment of patients with epidermal growth factor receptor (EGFR)-expressing metastatic colorectal cancer (mCRC).
  • The revised indication now includes a statement that retrospective subset analyses of metastatic or advanced colorectal cancer trials have not shown a treatment benefit for Erbitux in patients whose tumors had K-ras mutations in codon 12 or 13.
  • ImClone Systems, Bristol-Myers Squibb, and Lilly recommend that all patients should be tested for K-ras mutational status when considering treatment options for colorectal cancer patients.
  • The American Society of Clinical Oncology and the National Comprehensive Cancer Network have issued guidelines recommending that all mCRC patients be tested for K-ras gene mutations prior to treatment with an anti-EGFR monoclonal antibody therapy.
  • An estimated 40 percent of patients with mCRC have K-ras mutations, while the majority, approximately 60 percent, have a wild-type K-ras gene.
  • Signal transduction through the EGFR results in activation of wild-type K-ras protein, but in cells with activating K-ras somatic mutations, the mutant K-ras protein is continuously active and appears independent of EGFR regulation.

Statistics:

  • 40 percent of patients with mCRC have K-ras mutations.
  • 60 percent of patients with mCRC have a wild-type K-ras gene.
  • The labeling revisions include a modification to the indication, which affects approximately 40 percent of patients with mCRC.
  • The revised indication now includes a statement that retrospective subset analyses of metastatic or advanced colorectal cancer trials have not shown a treatment benefit for Erbitux in patients whose tumors had K-ras mutations in codon 12 or 13.

Sources:

  • FDA (no date)
  • ImClone Systems (no date)
  • Bristol-Myers Squibb (no date)
  • American Society of Clinical Oncology (no date)
  • National Comprehensive Cancer Network (no date)