Irinotecan

Pharmacogenomic Information in the Context of the FDA-Approved Drug Label*

The FDA recommends, but does not require, genetic testing prior to initiating treatment with irinotecan.

Excerpt from the irinotecan drug label:

"When administered in combination with other agents, or as a single-agent, a reduction in the starting dose by at least one level of CAMPOSTAR should be considered for patients known to be homozygous for the UGT1A1*28 allele..."

Patients homozygous for the UGT1A1*28 allele, a genetic polymorphism present in approximately 10% of the North American population that leads to reduced UGT1A1 enzyme activity, are at increased risk for neutropenia resulting from treatment with irinotecan. Individuals heterozygous for the UGT1A1 allele may be at increased risk for neutropenia. UGT1A1 catalyzes the conjugation of the highly active irinotecan metabolite SN-38 to the less-active SN-38 glucuronide.

For the complete drug label text with sections containing pharmacogenetic information highlighted, see the Irinotecan drug label PDF.

Pharmacogenomic Diagnostic Testing

The information below is provided for educational purposes only and does not constitute an endorsement of any listed test or manufacturer.

Drug PGx Diagnostic Test¹ Gene Variants Assayed FDA Document²
irinotecan Invader UGT1A1 Molecular Assay UGT1A1 UGT1A1*28 CLIA Document and 510(K) PMN Number K051824

¹ Entries in this column link to test manufacturer's website.
² Information in this column was found using searches of the entire FDA website (http://www.fda.gov/search.html), searches of the FDA CDRH CLIA database (http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfClia/Search.cfm), or searches of the FDA CDRH Premarket Approval Database (http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfPMA/pma.cfm).

Table updated 4/15/2009.

Related PharmGKB Resources:

Drug information: Irinotecan
Variants listed in drug label: UGT1A1*28
Very Important Pharmacogene (VIP) pages: UGT1A1 VIP
Allele frequency information: Not available
Gene pages: UGT1A1
Gene Variants pages: UGT1A1 variants
Pathways: Irinotecan Pathway, Irinotecan Pathway (Cancer)
Datasets: Irinotecan datasets
Genetics information: All variant annotations mentioning irinotecan
Literature: Publications related to irinotecan PGx

*Disclaimer: The contents of this page have not been endorsed by the FDA and are the sole responsibility of PharmGKB.

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