Uridine Diphosphate Glucuronosyltransferase 1A1 Genotyping Research Articles

Individual Irinotecan Therapy Under the Guidance of Pre-Treated UGT1A1*6 Genotyping in Gastric Cancer.

Background: Severe delayed diarrhea and hematological toxicity limit the use of irinotecan. Uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) is a critical enzyme in irinotecan metabolism. The study aims to investigate the safety and efficacy of irinotecan under the guidance of the pre-treatment UGT1A1 genotype in the second-line treatment of gastric cancer. Methods: This study involved 110 patients. Irinotecan was injected intravenously every 3 weeks, and the dose of irinotecan was determined by polymorphism of the UGT1A1 gene, which was divided into three groups (125 mg/m2: GG type; 100 mg/m2: GA type; 75 mg/m2: AA type). The primary end point was overall survival (OS), the secondary end points were progression-free survival (PFS) and safety. Results: One hundred and seven patients received irinotecan treatment and three patients with AA type received paclitaxel treatment. Among 107 patients, there were no significant differences in PFS (4.8 m vs 4.9 m vs 4.4 m; p = 0.5249) and OS (9.3 m vs 9.3 m vs NA; p = 0.6821) among patients with GG/GA/AA subtypes after dose adjustment. For the patient with homozygosity mutation, treatment was switched to paclitaxel. There were no significant differences in PFS and OS among patients with different alleles or after dose adjustment (p > 0.05). There was a significant difference in the risk of delayed diarrhea (p = 0.000), leukopenia (p = 0.003) and neutropenia (p = 0.000) in patients with different UGT1A1*6 genotypes, while no difference in patients with different UGT1A1*28 genotypes. Additionally, grade 3/4 diarrhea, neutropenia, and leukopenia were significantly more common in AA genotype patients compared to GG (2%, 19%, 24%) or GA (23%, 31%, 31%) genotype patients. Conclusion: Individual irinotecan treatment shows encouraging survival and tolerability outcomes in patients with GG/GA subtype. Irinotecan may be not suitable for patients with AA subtype.

Abstract 5250: Association between UGT1A1 gene polymorphism and safety and efficacy of irinotecan monotherapy as the second-line treatment for advanced gastric cancer

Abstract Objective: Uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) is a key enzyme in irinotecan metabolism. However, the relationship between UGT1A1 genotype and the safety and efficacy of irinotecan monotherapy in the treatment of Chinese advanced gastric cancer remains unclear. Methods: A total of 110 patients were enrolled. Intravenous irinotecan was administered every 3 weeks. Irinotecan dose was selected according to the polymorphism of UGT1A1 gene, which was divided into 3 groups: UGT1A1*6 wild-type (GG type): 125mg/m2, d1, d8; UGT1A1*6 mutant heterozygosity (GA type) 100mg/m2, d1, d8; UGT1A1*6 homozygosity mutation (AA type) 75mg/m2, d1, d8 or paclitaxel 125mg/m2, d1, d8. UGT1A1 genotypes were determined by direct sequencing or next-generation sequencing of genomic DNA extracted from peripheral blood. Results: Among 110 patients of the subjects, the genotypes of UGT1A1*28 were wild-type in 78 patients (70.91%), mutant heterozygosity in 28 (25.45%) and mutant homozygosity in 4 (3.64%). UGT1A1*6 were GG in 67 cases (60.91%), GA in 35 cases (31.82%), and AA in 8 cases (7.27%). There were two heterozygous mutations in 3 patients, and no homozygous mutation was detected. A total of 10 cycles of irinotecan were administered, with a median of five cycles per patient. There was no significant difference in the risk of delayed diarrhea and granulocytopenia in patients with different UGT1A1*28 genotypes (P>0.05), while there was significant difference in the risk of delayed diarrhea and granulocytopenia in patients with different UGT1A1*6 genotypes (P<0.05). The dose intensity of irinotecan was different in patients with different subtypes of UGT1A1*6 gene, and the dose intensity of heterozygous mutant patients was lower than that of wild-type patients. However, there were no significant differences in PFS and OS among patients with different subtypes after dose adjustment and program adjustment (P>0.05). Conclusion: UGT1A1*6 gene polymorphism was significantly associated with diarrhea and neutropenia induced by irinotecan. The safety and effectiveness of antitumor therapy might be significantly improved by individualized drug administration according to the results of UGT1A1*6 gene polymorphism. Citation Format: Huifang Lv, Yunduan He, Caiyun Nie, Beibei Chen, Jianzheng Wang, Weifeng Xu, Jing Zhao, Xiaobing Chen, Junling Zhang. Association between UGT1A1 gene polymorphism and safety and efficacy of irinotecan monotherapy as the second-line treatment for advanced gastric cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5250.

P-95 Bevacizumab, irinotecan and biweekly trifluridine/tipiracil for pretreated metastatic colorectal cancer: MODURATE, a phase Ib study

Treatment of refractory metastatic colorectal cancer (mCRC) with trifluridine/tipiracil yields some survival benefits. Trifluridine/tipiracil combined with bevacizumab or irinotecan suggested enhanced therapeutic effects in preclinical models. A phase Ib study combining standard trifluridine/tipiracil regimens with irinotecan resulted in better antitumor activity, accompanied by a high degree of febrile neutropenia. This phase Ib study of trifluridine/tipiracil, irinotecan, and bevacizumab in previously treated mCRC was conducted at two centers, Shizuoka Cancer Center and Aichi Cancer Center in Japan, and consisted of dose escalation (3+3 design) and expansion cohorts. Key eligibility criteria included histologically confirmed colorectal adenocarcinoma, failure or intolerant to fluoropyrimidine and oxaliplatin, no prior therapy with trifluridine/tipiracil and irinotecan, age of 20–75 years, and ECOG PS of 0–1. Patients received trifluridine/tipiracil (25–35 mg/m2 twice daily on days 1–5), irinotecan (150–180 mg/m2; day 1), and bevacizumab (5 mg/kg; day 1) every 2 weeks. The recommended phase II dose (RPTD) in the dose escalation cohort was administered to at least 15 patients in both cohorts. A total of 28 patients from two centers were enrolled between August 2016 and January 2020, comprising 18 in dose escalation cohort and 10 additional patients in expansion cohort. Five dose-limiting toxicities were observed in dose escalation cohort. RPTD was defined as trifluridine/tipiracil 35 mg/m2, irinotecan 150 mg/m2, and bevacizumab 5 mg/kg. Of the 16 patients who received RPTD, patients characteristics were as follows; median age (range), 64 (38-73) years; male/female, 11/5; PS 0/1, 13/3; right-/left-sided tumor, 1/15; median number of metastatic site (range), 2 (1-5); RAS mutant/wild-type, 9/7; uridine diphosphate glucuronosyltransferase 1A1 genotype wild/single hetero/double hetero or homo, 7/8/1; prior history of bevacizumab/anti-EGFR antibody, 6/4. The most common grade 3/4 adverse events were neutropenia (86%) and leukopenia (63%) without febrile neutropenia. No treatment-related death was observed. Dose reduction, delay, and discontinuation occurred in 94%, 94%, and 6% of patients, respectively. At a median follow-up time (range) of 417 (346–611) days, the overall response rate was 19%, with 3 patients achieving a partial response. The disease control rate was 75%, with an additional 9 patients exhibiting stable disease for >4 months duration in 5 patients. The median progression-free survival and overall survival were 7.1 (95% confidence interval [CI], 3.7–not reached [NR]) months and 21.7 (95% CI, 11.3–NR) months, respectively. Biweekly administration of trifluridine/tipiracil, irinotecan, plus bevacizumab may decrease febrile neutropenia with moderate antitumor activity in previously treated mCRC patients. Further investigation of this combination therapy is required.

Comparison of UGT1A1 Polymorphism as Guidance of Irinotecan Dose Escalation in RAS Wild-Type Metastatic Colorectal Cancer Patients Treated With Cetuximab or Bevacizumab Plus FOLFIRI as the First-Line Therapy.

Uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) polymorphism plays a crucial role in the increased susceptibility and toxicity of patients to irinotecan. This retrospective, observational study compared the clinical outcomes and adverse events (AEs) in RAS wild-type metastatic colorectal cancer (mCRC) patients treated with cetuximab or bevacizumab plus FOLFIRI with UGT1A1 genotyping and irinotecan dose escalation as the first-line therapy. In total, 173 patients with mCRC with RAS wild-type were enrolled. Among them, 98 patients were treated with cetuximab, whereas 75 patients were treated with bevacizumab. All patients received irinotecan dose escalation based on UGT1A1 genotyping. We compared the progression-free survival (PFS), overall survival (OS), objective response rates (ORRs), disease control rates (DCRs), metastatectomy, and severe adverse events (SAEs) between the two groups. The clinical effects of primary tumor sidedness and target therapy crossover were further analyzed. Over a median follow-up of 23.0 months [interquartile range (IQR), 15.0–32.5 months], no significant differences were observed between the cetuximab and bevacizumab groups in PFS [18.0 months vs. 14.0 months; 95% confidence interval (CI), 0.517–1.027; hazard ratio (HR), 0.729; p = 0.071], OS (40.0 months vs. 30.0 months; 95% CI, 0.410–1.008; HR, 0.643; p = 0.054), ORR (65.3% vs. 62.7%; p = 0.720), DCR (92.8% vs. 86.7%; p = 0.175), metastatectomy (36.7% vs. 29.3%; p = 0.307), and SAEs (p = 0.685). Regardless of primary tumor sidedness and target therapy crossover, no significant differences were noted in efficacy and safety between the two groups (all p > 0.05). Our results revealed that patients with wild-type RAS mCRC, regardless of biologics, with UGT1A1 genotyping can tolerate escalated doses of irinotecan and potentially achieve a more favorable clinical outcome without significantly increased toxicity.

Regorafenib plus FOLFIRI with irinotecan dose escalated according to uridine diphosphate glucuronosyltransferase 1A1genotyping in previous treated metastatic colorectal cancer patients:study protocol for a randomized controlled trial

BackgroundRegorafenib is an oral multikinase inhibitor for metastatic colorectal cancer (mCRC) previously treated with fluoropyrimidines, irinotecan, oxaliplatin, monoclonal antibodies targeting vascular endothelial growth factor, and monoclonal antibodies targeting epidermal growth factor receptor. A dose reduction from 160 mg to 120 mg regorafenib reduces regorafenib-associated adverse events (AEs). Dose adjustment of irinotecan in a 5-fluorouracil/leucovorin/irinotecan (FOLFIRI) regimen on the basis of an individual uridine diphosphate glucuronosyl transferase 1A1 (UGT1A1) genotype provides optimal oncological outcomes with acceptable AEs. The aim of this study is to address the efficacy and safety of a dose-adjusted combination of regorafenib and FOLFIRI for patients with mCRC.MethodsA prospective, multicenter, randomized in a 2:1 ratio, controlled, clinical trial with two parallel arms will be conducted to compare irinotecan dose-escalated FOLFIRI according to UGT1A1 genotyping plus 120 mg regorafenib with 120 mg regorafenib alone in previously treated patients with mCRC. The primary endpoint is progression-free survival, and the secondary endpoints are overall survival, disease control rate, time to progression, and duration of treatment. Safety assessments will also be recorded.DiscussionDose adjustment for regorafenib and irinotecan makes treatment-related AEs tolerable and makes the concomitant treatment practicable. This study will provide initial evidence regarding the efficacy and safety of a new combination of chemotherapy and a targeted agent for mCRC.Trial registrationClinicalTrials.gov, NCT03880877. Prospectively registered on 19 March 2019.

A UGT1A1 genotype-guided dosing study of modified FOLFIRINOX in previously untreated patients with advanced gastrointestinal malignancies.

FOLFIRINOX (5-fluorouracil [5-FU], leucovorin, irinotecan, oxaliplatin) is an effective but toxic therapy for pancreatic cancer. UGT1A1 (UDP glucuronosyltransferase 1A1) eliminates the active metabolite of irinotecan. Polymorphisms reduce UGT1A1 activity, leading to toxicity. The primary objective was to determine the dose-limiting toxicity (DLT) rate in cycle 1 of modified FOLFIRINOX (mFOLFIRINOX) using genotype-guided dosing of irinotecan for the most common UGT1A1 genotypes (*1/*1, *1/*28) in advanced gastrointestinal malignancies, with expansion in pancreatic and biliary tract cancers. 5-FU (2400 mg/m2 over 46 hours), leucovorin (400 mg/m2 ), oxaliplatin (85 mg/m2 ), and irinotecan were given every 14 days. Irinotecan doses of 180, 135, and 90 mg/m2 were administered for UGT1A1 genotypes *1/*1, *1/*28, and *28/*28, respectively. Prophylactic pegfilgrastim was omitted in cycle 1 for cohort 1 (tolerability by genotype), but was given in cohort 2 (tolerability by tumor type). Doses were tolerable if the upper limit of a 2-sided 80% confidence interval for DLT rate was ≤33%. In cohort 1, DLTs (most commonly febrile neutropenia, fatigue, diarrhea) occurred in 2/15 (13%), 3/16 (19%), and 4/10 (40%) patients with *1/*1, *1/*28, and *28/*28 genotypes, respectively. In cohort 2, 6/19 (32%) pancreatic and 4/19 (21%) biliary tract cancer patients experienced DLTs (most commonly fatigue, diarrhea, nausea/vomiting). In cohort 2, upper confidence limits of DLT rates exceeded 33%. Response rates were 38% in pancreatic and 21% in biliary tract cancers. On the basis of our prespecified criteria, tolerability of UGT1A1 genotype-guided mFOLFIRINOX was not established in pancreatic and biliary tract cancers. However, this regimen was effective.

Oncologic Outcomes in Metastatic Colorectal Cancer with Regorafenib with FOLFIRI as a Third- or Fourth-Line Setting

BACKGROUND: To evaluate the efficacy and toxicities of regorafenib plus irinotecan, dose-escalated on the basis of uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) genotyping, in previously heavily treated metastatic colorectal cancer (mCRC) and the prognostic values of EGFR expression, KRAS mutations, and tumor sidedness. METHODS: Forty-one patients with mCRC with disease progression after treatment with fluoropyrimidines, oxaliplatin, irinotecan, anti-VEGF, and anti-EGFR MoAbs were subjected to UGT1A1 genotyping and received regorafenib combined with FOLFIRI with dose-escalated irinotecan. RESULTS: The median follow-up period was 10.0 months (1.3-23.5 months). The overall disease control rate was 58.5%, whereas the median progression-free survival (PFS) and overall survival (OS) were 6.0 months and 12.0 months, respectively. KRAS mutations were significantly associated with positive EGFR expression (P = .026). KRAS mutations significantly correlated with a shorter OS than KRAS wild-type (6.0 vs. 14.4 months, P = .014) but had no significant association with PFS. Positive EGFR expression had an inverse correlation with PFS (2.5 vs. 14.0 months, P = .039) and OS (9.6 vs. 19.7 months, P = .044). Moreover, left-sided tumors associated with superior PFS (2.0 vs. 7.0 months, P < .0001) and OS (4.0 vs. 13.0 months, P < .0001), and tumor sidedness was an independent prognostic factor by the multivariate analysis. CONCLUSION: Regorafenib and FOLFIRI concomitant therapy with dose-escalated irinotecan seemed to be potentially practicable with satisfactory oncological results. KRAS mutations and EGFR expression might be predictors of poor oncological outcomes; however, left-sided mCRCs would be more beneficial for concomitant regorafenib and FOLFIRI therapy.

Association of nephrotoxicity during platinum-etoposide doublet therapy with UGT1A1 polymorphisms in small cell lung cancer patients

ObjectivesEtoposide is a key agent in the treatment of small cell lung cancer (SCLC). Uridine diphosphate (UDP)–glucuronosyltransferase 1A1 (UGT1A1) is thought to be largely responsible for the glucuronidation of etoposide as well as that of irinotecan, suggesting that polymorphisms of UGT1A1 might be predictive of etoposide toxicity. We therefore examined the relation between UGT1A1 polymorphisms and toxicity profile during platinum-etoposide doublet therapy in SCLC patients. Materials and MethodsSCLC patients who underwent platinum-etoposide doublet therapy and molecular testing for UGT1A1 genotype were reviewed for the occurrence of adverse events during treatment. ResultsA total of 41 SCLC patients received platinum-etoposide doublet therapy and were genotyped for UGT1A1*6 and UGT1A1*28 alleles. These alleles were detected in 15 (36.6%) patients, with the genotypes of *6/–, *6/*6, *28/–, *28/*28, or *6/*28 being observed in 9 (22.0%), 2 (4.9%), 2 (4.9%), 1 (2.4%), and 1 (2.4%) patients, respectively. The presence of these alleles was significantly associated with an increase in serum creatinine concentration of grade ≥2 (incidence of 66.7% for patients with the alleles versus 11.5% for those without, P < 0.001). Multivariate analysis also showed that these UGT1A1 alleles were significantly associated with therapy-induced nephrotoxicity (odds ratio of 19.30, 95% confidence interval of 2.50–149.00, P < 0.005). Although the differences did not achieve statistical significance, the incidence of other severe toxicities including febrile neutropenia was also slightly higher in patients with the UGT1A1*6 or UGT1A1*28 alleles than in those without them. ConclusionOur results reveal an association between UGT1A1 polymorphisms and toxicity of platinum-etoposide doublet therapy in SCLC patients, suggesting that close monitoring for toxicity, especially nephrotoxicity, is warranted for patients with such variant alleles receiving this treatment.

Influence of UGT1A1 polymorphism on etoposide plus platinum-induced neutropenia in Japanese patients with small-cell lung cancer.

The association between UGT1A1 polymorphism and etoposide-induced toxicities is still not clear. The aim of this study was to assess the association between uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) gene polymorphism and severe hematologic toxicities in Japanese patients receiving etoposide plus platinum chemotherapy for small-cell lung cancer. This retrospective analysis included patients with small-cell lung cancer who had received their first-line chemotherapy with etoposide plus cisplatin or carboplatin, between October 2008 and April 2018, at the University of Fukui Hospital. The relationship between UGT1A1 polymorphisms and first-cycle neutropenia as well as thrombocytopenia was evaluated. A total of 55 patients were enrolled. The incidence of grade 4 neutropenia during the first cycle of etoposide-based chemotherapy was higher in patients with homozygous (hmz) polymorphisms for UGT1A1*28 and *6 (*28/*28, *6/*6, and *6/*28) than in patients with wild-type (wt) (*1/*1) and heterozygous (htz) (*1/*28 and *1/*6) polymorphisms (88% vs 43% P = 0.03). The incidence of febrile neutropenia and grade 4 thrombocytopenia, however, was not significantly different. Multivariate analysis suggested that grade 4 neutropenia associated significantly with an hmz UGT1A1 genotype [odds ratio (OR) 11.3; P = 0.04] and administration of granulocyte colony-stimulating factor (G-CSF) before the neutrophil counts dropped to < 500 cells/µL (OR; P = 0.01). UGT1A1*28 and UGT1A1*6 mutations might be regarded as predictors for etoposide-induced grade 4 neutropenia.

Effect of UDP-Glucuronosyltransferase (UGT) 1A Polymorphism (rs8330 and rs10929303) on Glucuronidation Status of Acetaminophen.

Interindividual variability in polymorphic uridine diphosphate-glucuronosyltransferase 1A1 (UGT1A1) ascribed to genetic diversity is associated with relative glucuronidation level among individuals. The present research was aimed to study the effect of 2 important single nucleotide polymorphisms (SNPs; rs8330 and rs10929303) of UGT1A1 gene on glucuronidation status of acetaminophen in healthy volunteers (n = 109). Among enrolled volunteers, 54.13% were male (n = 59) and 45.87% were female (n = 50). The in vivo activity of UGT1A1 was investigated by high-performance liquid chromatography-based analysis of glucuronidation status (ie, acetaminophen and acetaminophen glucuronide) in human volunteers after oral intake of a single dose (1000 mg) of acetaminophen. The TaqMan SNP genotyping assay was used for UGT1A1 genotyping. The wild-type genotype (C/C) was observed the most frequent one for both SNPs (rs8330 and rs10929303) and associated with fast glucuronidator phenotypes. The distribution of variant genotype (G/G) for SNP rs8330 was observed in 5% of male and 8% of the female population; however, for SNP rs10929303, the G/G genotype was found in 8% of both genders. A trimodal distribution (fast, intermediate, and slow) based on phenotypes was observed. Among the male participants, the glucuronidation phenotypes were observed as 7% slow, 37% intermediate, and 56% fast glucuronidators; however, these findings for the females were slightly different as 8%, 32%, and 60% respectively. The k-statistics revealed a compelling evidence for good concordance between phenotype and genotype with a k value of 1.00 for SNP rs8330 and 0.966 for SNP rs10929303 in our population.

Regorafenib Plus FOLFIRI With Irinotecan Dose Escalated According to Uridine Diphosphate Glucuronosyltransferase 1A1 Genotyping in Patients With Metastatic Colorectal Cancer.

We analyzed the results of previously treated patients with metastatic colorectal cancer (mCRC) who received regorafenib plus FOLFIRI with the irinotecan dose escalation on the basis of uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) genotyping. Thirteen patients with previously treated mCRC were subjected to UGT1A1 genotyping between October 2013 and June 2015 and were administered regorafenib plus FOLFIRI with irinotecan dose escalation. Patients with UGT1A1*1/*1 and *1/*28 genotypes were administered 180 mg/m2 of irinotecan, whereas those with the UGT1A1*28/*28 genotype were administered 120 mg/m2 of irinotecan. For all patients, the irinotecan dose was increased by 30 mg/m2 every two cycles until grade ≥3 adverse events or severe adverse events developed, following which the dose was reverted to and maintained at the previously tolerated level. The oral regorafenib dose was adjusted to 120 mg/day daily. The median follow-up period was 10.0 months (1.0–21.0 months). The disease control rate was 69.2%, whereas the median progression-free survival and overall survival were 9.5 and 13.0 months, respectively. Our findings indicate that regorafenib plus FOLFIRI with irinotecan dose escalation based on UGT1A1 genotyping in previously treated patients with mCRC and with UGT1A1*1/*1 and UGT1A1*1/*28 genotypes is clinically effective and yields improved oncological outcomes.

Association between UGT1A1*28*28 genotype and lung cancer in the Japanese population.

Lung cancer is the leading cause of cancer death and is closely linked to tobacco smoking. Genetic polymorphisms in genes that encode enzymes involved in metabolizing tobacco carcinogens could affect an individual's risk for lung cancer. While polymorphism of UDP-glucuronosyltransferase1A1 (UGT1A1) is involved in detoxification of benzo(a)pyrene-7,8-dihydrodiol(-), a major tobacco carcinogen, the association between UGT1A1 genotype and lung cancer has not been examined. We retrieved the clinical data of 5,285 patients who underwent systemic chemotherapy at Kyoto University Hospital. A total of 765 patients (194 lung cancer patients and 671 patients with other malignancies) with UGT1A1 genotyping data were included in this analysis. We used logistic regression with recessive, dominant, and additive models to identify differences in genotype frequencies between lung cancer and other malignancies. In the recessive model, UGT1A1*28*28 genotype was significantly associated with lung cancer compared to other malignancies (odds ratio5.3, P=0.0083). Among lung cancer patients with a smoking history, squamous cell carcinoma was significantly predominant in patients with UGT1A1*28*28 compared to those with other UGT1A1 genotypes (P=0.024). This is the first study to demonstrate a significant association between the homozygous UGT1A1*28 genotype and lung cancer.

Prospective analysis of UGT1A1 promoter polymorphism for irinotecan dose escalation in metastatic colorectal cancer patients treated with bevacizumab plus FOLFIRI as the first-line setting: study protocol for a randomized controlled trial.

BackgroundIrinotecan is approved and widely administered to metastatic colorectal cancer (mCRC) patients; however, it can cause severe toxicities including neutropenia and diarrhea. The polymorphisms of genes encoding drug-metabolizing enzymes can play a crucial role in the increased susceptibility of cancer patients to chemotherapy toxicity. Therefore, we plan to explore the effect of the genetic polymorphism of uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) for irinotecan detoxification in mCRC patients. This trial will compare the clinical outcomes and side effects observed in mCRC patients treated with bevacizumab plus 5-fluorouracil/leucovorin/irinotecan (FOLFIRI) with and without UGT1A1 genotyping and irinotecan dose escalation. A total of 400 mCRC patients were randomized into a study group and a control group.Methods/DesignThis trial is a prospective, multicenter, randomized clinical trial comparing UGT1A1 promoter polymorphism for irinotecan dose escalation in mCRC patients administered with bevacizumab plus FOLFIRI as the first-line setting. The enrolled patients were randomly assigned to one of two groups, a study group and a control group, on the basis of receiving UGT1A1 genotyping or not. The study group receive a biweekly FOLFIRI regimen, with irinotecan dose escalation based on UGT1A1 genotyping; whereas the control group receive the conventional biweekly FOLFIRI regimen without UGT1A1 genotyping. The clinicopathological features, response rates, toxicity, and progression-free survival or overall survival will be compared between the two groups.DiscussionPatients with mCRC undergoing UGT1A1 genotyping may receive escalated doses of irinotecan for a potentially more favorable clinical response and outcome, in addition to comparable toxicities. Such personalized medicine based on genotyping may be feasible for clinical practice.Trial registrationNCT02256800. Date of registration: 3 October 2014. Date of first patient randomized: 16 January 2015

Correlation of UGT1A1*28 and *6 polymorphisms with irinotecan-induced neutropenia in Thai colorectal cancer patients

UDP-glucuronosyltransferase1A1 (UGT1A1) polymorphisms have been related with irinotecan toxicity. The purpose of this study was to determine the associations between UGT1A1*28 and *6 polymorphisms and irinotecan toxicity in Thai patients with metastatic colorectal cancer. 44 metastatic colorectal cancer patients received irinotecan-based chemotherapy. Hematologic toxicities were determined in the first and second cycles of treatment. The genotypes of UGT1A1*28 and *6 were analyzed by pyrosequencing technique. The frequencies of genetic testing for UGT1A1*28 and *6 polymorphisms were 22.8% (TA6/TA7; 20.5%, TA7/TA7; 2.3%) and 15.9% (GA), respectively. No patients had the homozygous UGT1A1*6 (AA). Neither UGT1A1*28 nor UGT1A1*6 polymorphisms were significantly associated with severe hematologic toxicities. However, analysis of UGT1A1*28 and *6 in combination revealed an association with severe neutropenia in the first and second cycles (P = 0.044, P = 0.017, respectively). Both UGT1A1*28 and *6 polymorphisms may have an increased risk of irinotecan-induced neutropenia in Thai colorectal cancer patients.

The Association of Gilbert's Syndrome with Hyperbilirubinaemia Occurring on Any of Imatinib, Dasatinib and Nilotinib in Patients with Chronic Myeloid Leukaemia (CML)

Background: Individuals with Gilbert's syndrome present with mild, unconjugated hyperbilirubinaemia, resulting from impaired glucuronidation by reduced uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) expression. The A(TA)7TAA polymorphism responsible for the syndrome has been associated with nilotinib-induced hyperbilirubinaemia in patients with chronic myeloid leukaemia (CML). Our study extends UGT1A1 molecular analysis to a larger cohort of CML patients receiving other tyrosine kinase inhibitors (TKIs) and explores the relationship with other abnormalities of liver function.Methods: We interrogated our database of 832 patients treated with a TKI for CML at our center and identified 467 individuals who presented in first chronic phase, who had received only a TKI (prior interferon, combination experimental therapy, autologous and allogeneic transplant patients were all excluded) and for whom serial liver function results were available. We then performed PCR to identify variations in dinucleotide repeats in the UGT1A1 promoter region. Genotypes were assigned as follows: 6/6 (homozygous for (TA)6 allele; wild-type), 7/7 (homozygous for (TA)7allele) and 6/7 (heterozygous). Because individual patients may have received more than one TKI, we defined the period on treatment with each TKI as an 'episode' in order to be able to attribute abnormalities of liver function to a specific drug. Hyperbilirubinaemia was graded according to the Common Terminology Criteria for Adverse Events (CTCAE), version 4.0. Both ALT and ALP were defined as increased if they were above the upper limit of normal. To date we have completed the analysis for 340 patients comprising a total of 568 episodes of TKI therapy (imatinib 313, dasatinib 125, nilotinib 130).Results: The UGT1A1 genotype analysis showed six variants. The majority of patients displayed one of 6/6 (149 patients), 6/7 (138 patients) or 7/7 (48 patients) genotypes. Small numbers of patients with the 5/6, 5/7 and 6/8 genotypes were excluded from further analysis. Hyperbilirubinaemia was seen in patients with all three genotypes, but was more frequent in patients on nilotinib (44%), compared to imatinib (14%) and dasatinib (8%). The incidence of hyperbilirubinaemia in individuals with the 6/6 genotype was 6%, 0% and 22% for imatinib, dasatinib and nilotinib respectively, and 10%, 6% and 56% for patients with the 6/7 genotype. The frequency of hyperbilirubinaemia in those with the 7/7 genotype was significantly higher compared to the occurrence of such events in any other genotype, irrespective of treatment. However, it occurred more often in patients on nilotinib (80%), followed by imatinib (61%) and dasatinib (44%). A significantly higher number of patients with the 7/7 genotype on nilotinib reported Grade 3 hyperbilirubinaemia (25%), with no grade 3 events on imatinib and only one on dasatinib. Hyperbilirubinaemia on any single drug did not predict for this event on any subsequent drug.Further analysis of liver function tests (LFTs) and bilirubin levels divided episodes into four groups: 1. Episodes with normal bilirubin and normal LFTs (n = 273), 2. Episodes with isolated raised LFTs but normal bilirubin (n = 179), 3. Episodes with isolated hyperbilirubinaemia (n = 27) but normal LFTs and 4. Episodes with raised bilirubin and raised LFTs (n = 84). Abnormal LFTs with or without hyperbilirubinaemia were most commonly seen on nilotinib (65%) compared to imatinib (40%) and dasatinib (46%), confirming previous reports of the frequencies of transaminitis on the various TKIs. Isolated hyperbilirubnaemia was uncommon (<6%) on any of the drugs, but was more frequent in the 7/7 than the 6/6 or 6/7 genotypes for imatinib or dasatinib. Interestingly it was not seen in patients with the 7/7 genotype on nilotinib, as 80% of the 7/7 patients with hyperblirubinaemia on nilotinib had other abnormalities of liver function.Conclusion. We confirmed the increased risk of hyperbilirubinaemia in individuals with the A(TA)7TAA polymorphism when treated with nilotinib. In contrast to other reports, we found that all patients with the 7/7 genotype are susceptible to increases in bilirubin when treated with any of imatinib, dasatinib or nilotinib. Hyperbilirubinaemia most commonly occurs alongside elevations in LFTs on nilotinib, indicating a nilotinib-induced hepatotoxicity that is compounded by the additional UGT1A1 inhibition. DisclosuresMilojkovic:ARIAD Pharmaceuticals Inc.: Honoraria; Pfizer: Honoraria; BMS: Honoraria; Novartis: Honoraria. Apperley:Pfizer: Honoraria; Bristol Myers Squibb: Honoraria; Ariad: Honoraria; Novartis: Honoraria. Foroni:Bristol Myers Squibb: Research Funding; Novartis: Research Funding; Ariad: Research Funding.

Clinical observations on associations between the UGT1A1 genotype and severe toxicity of irinotecan.

Severe toxicity is commonly observed in cancer patients receiving irinotecan (CPT-11). UDP glucuronosyltransferase1A1 (UGT1A1) catalyzes the glucuronidation of the active metabolite SN-38 but the relationship between UGT1A1 and severe toxicity remains unclear. Our study aimed to assess this point to guide clinical use of CPT-11. 89 cancer patients with advanced disease received CPT-11-based chemotherapy for at least two cycles. Toxicity, including GI and hematologic toxicity was recorded in detail and UGT1A1 variants were genotyped. Regression analysis was used to analyse relationships between these variables and tumor response. The prevalence of grade III-IV diarrhea was 10.1%, this being more common in patients with the TA 6/7 genotype (5 of 22 patients, 22.7%) (p<0.05). The prevalence of grade III-IV neutropenia was 13.4%and also highest in patients with the TA 6/7 genotype (4 of 22 patients; 18.2%) but without significance (p>0.05). The retreatment total bilirubin levels were significantly higher in TA6/7 patients (mean, 12.75μmol/L) with compared to TA6/6 (mean, 9.92 μmol/L) with p<0.05. Our study support the conclusion that patients with a UGT1A1*28 allele (s) will suffer an increased risk of severe irinotecan-induced diarrhea, whether with mid-or low-dosage. However, the UGT1A1*28 allele (s) did not increase severe neutropenia. Higher serum total bilirubin is an indication that patients UGT1A1 genotype is not wild-type, with significance for clinic usage of CPT-11.

Feasibility study of irinotecan based on UGT1A1 polymorphisms for metastatic colorectal cancer: Interim report.

505 Background: Although Irinotecan prolongs survival, it causes severe diarrhea and neutropenia. Recent pharmacogenetic studies on irinotecan have revealed significant associations of UDP-glucuronosyltransferase 1A1 (UGT1A1) polymorphisms *28 and *6, the latter being specifically detected in East Asians resulting in severe toxicity. It is necessary that the dose-finding trial that decided the optimal dose according to the gene polymorphism to draw out the maximum therapeutic effect while evading the side effect. Previously, we showed UGT1A1 polymorphisms in Japanese patients (2011 ASCO-GI). Here, we present the interim report of prospective trial of the safety about FOLFIRI therapy according to each gene type of UGT1A1 for Japanese patients with advanced CRC. Methods: From 2008, 250 Japanese patients in TOKUSHIMA University were enrolled in this study. Homo group (*6/*6 and *28/*28 or a both hetero types), hetero group (It was *28 and either *6 was hetero type), and wild group (*28 and *6 were wild types) were defined. On the 30 patients with advanced CRC treated with FOLFIRI after standard chemotherapy, wild and homo groups were administered 150mg/m2 irinotecan, and homo group was 100mg/m2. The incidences of severe toxicities in each gene type of UGT1A1 and the response rate in FOLFIRI therapy were investigated. Results: In Japanese people, UGT1A1*6 polymorphisms were higher than *28 (*6 homo 3%, hetero 27% vs *28 homo 0.5%, hetero 13%). On the 30 patients with advanced CRC treated with FOLFIRI, the genotypes of UGT1A1*28 were homozygous in 1 (3%) and heterozygous in 6 (20%), *6 were homozygous in 0 and heterozygous in 8 (27%). In *6 heterozygous patients, severe toxicities (grade 3 or more) were found (38%). In *28 heterozygous patients, 1 patient (17%) showed severe toxicities. There was no decrease of irinotecan doses in each group. The number of course to PD was 7.6 (1-23). Regarding the response rate, PR, SD, PD was observed in 2 (7%), 6 (20%) and 18 patients (60%), respectively. Conclusions: In our interim report, the dosages of irinotecan based on UGT1A1 polymorphisms are safety in FOLFIRI therapy.

UGT1A1predicts outcome in colorectal cancer treated with irinotecan and fluorouracil

To evaluate effects of UDP-glucuronosyltransferase1A1 (UGT1A1) and thymidylate synthetase (TS) gene polymorphisms on irinotecan in metastatic colorectal cancer (mCRC). Two irinotecan- and fluorouracil-based regimens, FOLFIRI and IFL, were selected as second-line therapy for 138 Chinese mCRC patients. Genomic DNA was extracted from peripheral blood samples before treatment. UGT1A1 and TS gene polymorphisms were determined by direct sequencing and restriction fragment length polymorphism, respectively. Gene polymorphisms of UGT1A1*28, UGT1A1*6 and promoter enhancer region of TS were analyzed. The relationship between genetic polymorphisms and clinical outcome, that is, response, toxicity and survival were assessed. Pharmacokinetic analyses were performed in a subgroup patients based on different UGT1A1 genotypes. Plasma concentration of irinotecan and its active metabolite SN-38 and inactive metabolite SN-38G were determined by high performance liquid chromatography. Differences in irinotecan and its metabolites between UGT1A1 gene variants were compared. One hundred and eight patients received the FOLFIRI regimen, 29 the IFL regimen, and one irinotecan monotherapy. One hundred and thirty patients were eligible for toxicity and 111 for efficacy evaluation. One hundred and thirty-six patients were tested for UGT1A1*28 and *6 genotypes and 125 for promoter enhancer region of TS. Patients showed a higher frequency of wild-type UGT1A1*28 (TA6/6) compared with a Caucasian population (69.9% vs 45.2%). No significant difference was found between response rates and UGT1A1 genotype, although wild-type showed lower response rates compared with other variants (17.9% vs 24.2% for UGT1A1*28, 15.7% vs 26.8% for UGT1A1*6). When TS was considered, the subgroup with homozygous UGT1A1*28 (TA7/7) and non-3RG genotypes showed the highest response rate (33.3%), while wild-type UGT1A1*28 (TA6/6) with non-3RG only had a 13.6% response rate, but no significant difference was found. Logistic regression showed treatment duration was closely linked to clinical response. In toxicity comparison, UGT1A1*28 TA6/6 was associated with lower incidence of grade 2-4 diarrhea (27.8% vs 100%), and significantly reduced the risk of grade 4 neutropenia compared with TA7/7 (7.8% vs 37.5%). Wild-type UGT1A1*6 (G/G) tended to have a lower incidence of grade 3/4 diarrhea vs homozygous mutant (A/A) genotype (13.0% vs 40.0%). Taking UGT1A1 and TS genotypes together, lower incidence of grade 2-4 diarrhea was found in patients with non-3RG TS genotypes, when TA6/6 was compared with TA7/7 (35.3% vs 100.0%). No significant association with time to progression (TTP) and overall survival (OS) was observed with either UGT1A1 or TS gene polymorphisms, although slightly longer TTP and OS were found with UGT1A1*28 (TA6/6). Irinotecan PK was investigated in 34 patients, which showed high area under concentration curve (AUC) of irinotecan and SN-38, but low AUC ratio (SN-38G / SN-38) in those patients with UGT1A1*28 TA7/7. A distinct distribution pattern of UGT1A1 genotypes in Chinese patients might contribute to relatively low toxicity associated with irinotecan and 5-fluorouracil in mCRC patients.

Short Communication: Lack of Correlation Between UGT1A1*6, *28 Genotypes, and Plasma Raltegravir Concentrations in Japanese HIV Type 1-Infected Patients

Raltegravir is metabolized by glucuronidation via UDP-glucuronosyltransferase 1A1 (UGT1A1). We analyzed the genotypes of UGT1A1 (*6, *27, and *28) and their contribution to plasma raltegravir concentrations in 56 Japanese HIV-1-infected patients in the National Hospital Organization Nagoya Medical Center of Japan. Among the 56 patients, the UGT1A1 genotype in two patients was *6 homozygote. Heterozygous variants were found in 13 patients for *6 and in 11 patients for *28, while all of the patients were found to carry wild-type sequences at the position corresponding to the *27 allele. Plasma raltegravir concentration of a male patient with *6 homozygote (0.53 μg/ml) was modestly higher than that of patients with wild type (0.12 μg/ml) or *6 heterozygote (0.16 μg/ml). Another female patient with the *6 homozygote had a low plasma raltegravir concentration (0.03 μg/ml). Patients heterozygous for the *6 or *28 allele did not display significantly different plasma raltegravir concentrations compared to patients homozygous for the respective wild-type allele. Thus, in the present study, we showed that heterozygous reduced-function *6 and *28 alleles appear to have no significant effect on plasma raltegravir concentrations in Japanese HIV-1-infected patients. However, variability in raltegravir concentration and small patient population precluded a correlation between UGT1A1*6 homozygosity and plasma raltegravir concentration. To clarify the contribution of UGT1A1*6 or *28 polymorphisms to plasma raltegravir concentrations, further investigations on larger subject populations are required.

Regimen Selection for First-line FOLFIRI and FOLFOX Based on UGT1A1 Genotype and Physical Background is Feasible in Japanese Patients with Advanced Colorectal Cancer

We examined the feasibility of regimen selection for first-line irinotecan, 5-fluorouracil and leucovorin or oxaliplatin, 5-fluorouracil and leucovorin in Japanese patients with advanced colorectal cancer based on UDP-glucuronosyltransferase 1A1 genotype as well as physical status of patients related to diarrhea. As first-line irinotecan, 5-fluorouracil and leucovorin is a little bit superior to oxaliplatin, 5-fluorouracil and leucovorin with respect to efficacy and toxicity, patients without risk factors of irinotecan-induced toxicity were first assigned to irinotecan, 5-fluorouracil and leucovorin. Patients with UDP-glucuronosyltransferase 1A1 28/ 28, 6/ 6, 28/ 6 or 28/ 27 and those with ascites, peritoneal dissemination or diarrhea first received oxaliplatin, 5-fluorouracil and leucovorin to avoid the irinotecan-induced neutropenia and diarrhea, respectively. We retrospectively evaluated the feasibility of this strategy by assessing toxicity and total progression-free survival in first- and subsequent second-line therapies in all patients studied. In the first-line irinotecan, 5-fluorouracil and leucovorin (n = 61), Grade 4 neutropenia, febrile neutropenia and Grade 3 diarrhea occurred in 8.2, 3.3 and 3.3% of patients, respectively. In the first-line oxaliplatin, 5-fluorouracil and leucovorin (n = 26), Grade 4 neutropenia, febrile neutropenia, Grade 3 thrombocytopenia and Grade 3 neuropathy were observed in 11.5, 3.8, 3.8 and 7.7% of patients, respectively. In the second-line oxaliplatin, 5-fluorouracil and leucovorin (n = 38), Grade 3 diarrhea occurred in 2.6% of patients. In the second-line irinotecan monotherapy (n = 11), Grade 4 or febrile neutropenia occurred in 18% of patients and Grade 3 diarrhea in 9.1% of patients. In second-line S-1 (n = 9), Grade 3 anemia occurred in 2 patients. Median total progression-free survival in all 87 patients was 11.5 months. Present regimen selection strategy would be feasible, since it causes less toxicity and similar efficacy comparing to previous studies. Determination of appropriate reduced dose in the second-line irinotecan monotherapy or other standard second-line therapy for patients with high-risk to irinotecan-induced toxicity might make this strategy more effective.