Table 2.

Pharmacogenetics information on the UDP glucuronosyltransferase family 1 member A1 gene (UGT1A1) for irinotecan‐related adverse reactions in selected countries

Country	UGT1A1 pharmacogenomic information in package insert (section)
Taiwan	(Warning and precautions) UGT1A1*28 homozygotes should be administered the normally indicated starting dose. The haematological toxicity of the patients should be monitored
Singapore	(Warning and precautions) Patients with UGT1A1*6 or *28 homozygotes or compound heterozygotes may be at increased risk of serious adverse reactions, especially neutropenia, caused by reduced glucuronidation of SN‐38. Caution should be exercised when administering irinotecan to such patients. The haematological toxicity of the patients should be monitored
Japan	(Pharmacokinetics) UGT1A1*6/*28 – neutropenia association is mentioned in referenced papersa
USA	(Warning and precautions) UGT1A1*28 homozygotes are at increased risk of neutropenia
	(Dosage and administration) A reduction in the starting dose by at least one level should be considered for UGT1A1*28 homozygous patients
Canada	(Warning and precautions) A reduced starting dose should be considered for UGT1A1*28 homozygous patients
UK	(Pharmacodynamic properties) UGT1A1*28 homozygotes should be administered the normally indicated starting dose. A reduced starting dose should be considered for patients who have experienced haematological toxicity with previous treatment
Australia	(Precautions) Same as in the UK

^aPharmacogenetics/genomics test reimbursed by national health insurance