Cost evaluation of irinotecan-related toxicities associated with the UGT1A1*28 patient genotype

The adoption of a pre-emptive UGT1A1*28 genotyping to increase irinotecan safety in clinical practice is still limited. This is the first actual study of costs associated to the management of irinotecan-related toxicity, and their association with UGT1A1*28 genotype. A retrospective analysis of the cost of toxicity management was conducted on 243 metastatic colorectal cancer patients enrolled in a clinical trial and treated with standard of care FOLFIRI. The mean predicted cost per patient was higher for *28/*28 (4,886€), versus *1/*1 (812€), (regression coefficient 1.79, 95%CI=1.31-2.28; P<0.001) and for *1/*28 (1,119€) versus *1/*1 (regression coefficient 0.32, 95%CI=0.04-0.60; P=0.024). This is consistent with a different grade 4 toxicity profile among the three genotypes, and a higher frequency of costly interventions like hospitalization among patients with the *28 allele. A differential toxicity management cost by *28 genotype is herein demonstrated, representing a first step towards a demonstration of the test clinical utility. This article is protected by copyright. All rights reserved.