A phase-II study based on dose adjustment according to UGT1A1 polymorphism: is irinotecan underdosed in first-line FOLFIRI regimen for mCRC?

PURPOSE: Irinotecan has considerable importance in the treatment of metastatic colorectal cancer (mCRC). UDP-glucoronyltransferase (UGT) 1A1 is responsible for the inactivation of SN-38, a metabolite of irinotecan. Depending on UGT1A1 polymorphism, the activity of the UGT enzyme can be reduced leading to more frequent occurrence of adverse events related to irinotecan. The present study aimed to assess the safety and efficacy of different doses of irinotecan adjusted according to UGT1A1 polymorphism. METHODS: Thirty-four patients treated with FOLFIRI as first-line treatment for mCRC were included in this study. The irinotecan dosage was adapted on the basis of UGT1A1 polymorphisms: *1/*1 (370 mg/m2); *1/*28 (310 mg/m2), and *28/*28 (180 mg/m2). The incidence of grades 3 and 4 toxicities (neutropenia, febrile neutropenia, and diarrhoea) was recorded. Response was assessed according to the RECIST 1.1 criteria. RESULTS: On the basis of UGT1A1 genotyping, 20 patients were *1/*1 (58.8%), 12 were *1/*28 (35.3%) and 2 were *28/*28 (5.9%). Seven patients experienced at least one severe toxicity, i.e., 21% of the population, amounting to eleven adverse events. Concerning the response rate, 15 patients (44%) had partial or complete response. CONCLUSION: This study demonstrates that mCRC patients treated with FOLFIRI can tolerate a higher dose of irinotecan than the standard dose, i.e., > 180 mg/m2, on the basis of their UGT1A1 genotype, without increased toxicities. TRIAL REGISTRATION: NCT01963182 (registered on 16/10/2013, Clermont-Ferrand, France).

Real-World Outcomes of First-Line FOLFIRI Plus Bevacizumab with Irinotecan Dose Escalation versus FOLFOXIRI Plus Bevacizumab in BRAFV600E-Mutant Metastatic Colorectal Cancer: The Preliminary Data from a Single-Center Observational Study.

Background and Objectives: Approximately 5-10% of all patients with metastatic colorectal cancer (mCRC) harbor a BRAFV600E mutation. These patients exhibit distinct metastatic patterns, poor prognosis, and heterogenous survival outcomes. The findings from the TRIBE study indicated that the administration of FOLFOXIRI plus bevacizumab as first-line treatment extended the median duration of overall survival (OS). In this study, we explored the effects of UGT1A1 polymorphism on the outcomes of irinotecan dose escalation versus FOLFOXIRI plus bevacizumab in patients with BRAFV600E-mutant mCRC. Materials and Methods: We retrospectively reviewed the medical records of 25 patients who had received a diagnosis of BRAFV600E-mutant mCRC between October 2015 and August 2022. All patients underwent UGT1A1 genotyping before receiving bevacizumab plus FOLFIRI. The primary end point was progression-free survival (PFS), and secondary endpoints were OS and adverse events (AEs). The two treatment arms were compared in terms of 6-month PFS and 12-month OS. Results: Over a median follow-up duration of 15.0 (interquartile range, 10.0-30.5) months, no significant differences were noted between the treatment arms in severe AEs (SAEs), 6-month PFS, or 12-month OS (all p < 0.05). Regarding AEs, the FOLFIRI plus bevacizumab regimen was associated with a lower incidence of anorexia than was the FOLFOXIRI plus bevacizumab regimen (p = 0.042). Conclusions: Our findings indicate that FOLFIRI plus bevacizumab with irinotecan dose escalation is an effective first-line treatment regimen for patients with BRAFV600E-mutant mCRC. This regimen leads to acceptable clinical outcomes with manageable AEs. However, the effects on survival and safety outcomes could only be speculated, and further studies are needed because of the sample size, the follow-up for the OS evaluation, and the non-uniformity in all the variables considered in the two groups.

Predictive Value of ABCC2 and UGT1A1 Polymorphisms on Irinotecan-Related Toxicities in Patients with Cancer.

Background: There is extensive interindividual variability in response and tolerance to anticancer drugs. This heterogeneity provides a major limitation to the "rational" use of cytotoxic drugs, and it becomes a major problem in oncology giving a narrow therapeutic window with a vital risk. Among these anticancer drugs, irinotecan can cause dose-limiting toxicities, commonly diarrhea and neutropenia. Interaction among pathways of activation/inactivation (UGT1A1) and hepatobiliary transport of irinotecan and its metabolites could, in part, explain its interindividual variability. The objective of this study was to perform an exploratory analysis to evaluate the correlation between the genetic polymorphisms of UGT1A1 and ABCC2 with the different toxicities associated with irinotecan treatment. Materials and Methods: Seventy-five patients with solid cancers were included, all were administered an irinotecan-based regimen in both Mission Bay Medical Center; and Zuckerberg San Francisco General Hospital from May 2016 to December 2016. The patients' genotyping was performed for both the UGT1A1*28 polymorphism, and the ABCC2 - 1549G>A, and ABCC2 - 1249G>A single nucleotide polymorphism. Comparisons among qualitative data were assessed using the χ2-test, and Fisher's exact test in the case of small group sizes. Results: Diarrhea was observed in 40 patients (53.3%), among them only 9 patients had high grades diarrhea (grades III and IV). Grades III/IV of nausea were more frequently associated with the ABCC2-1549 AA genotype (83.3% p = 0.004) in patients with colorectal cancer. In pancreatic cancer, a significant absence of diarrhea grades III-IV was noted in patients with the ABCC2 1249 GG genotype compared to the other ABCC2 1249 genotypes.

Clinical and genetic risk factors associated with neonatal severe hyperbilirubinemia: a case-control study based on the China Neonatal Genomes Project.

Objective: We aimed to investigate the clinical and genetic risk factors associated with neonatal severe unconjugated hyperbilirubinemia. Methods: This was a retrospective, 1:1 matched, case-control study. We included 614 neonates diagnosed with severe unconjugated hyperbilirubinemia (serum total bilirubin level ≥425 µmol/L or serum total bilirubin concentration that met exchange transfusion criteria) from the China Neonatal Genomes Project in Children's Hospital of Fudan University. Clinical exome sequencing data were analyzed using a data analysis pipeline of Children's Hospital of Fudan University. The factors associated with severe unconjugated hyperbilirubinemia were assessed using univariable and multivariable logistic regression analyses. Interaction analyses were examined between clinical and genetic risk factors. Results: ABO/Rh incompatibility hemolysis (odds ratio [OR] 3.36, 95% confidence interval [CI] 2.32-4.86), extravascular hemorrhage (OR 2.95, 95% CI 2.24-3.89), weight loss (OR 5.46, 95% CI 2.88-10.36), exclusive breastmilk feeding (OR 3.56, 95% CI 2.71-4.68), and the homozygous mutant of UGT1A1 211G>A (OR 2.35, 95% CI 1.54-3.59) were all identified as factors significantly associated with severe unconjugated hyperbilirubinemia. The presence of UGT1A1 211G>A mildly increased the risk of severe unconjugated hyperbilirubinemia caused by ABO/Rh incompatibility hemolysis (OR 3.98, 95% CI 2.19-7.23), although the effect is not statistically significant. Conclusion: ABO/Rh incompatibility hemolysis, extravascular hemorrhage, weight loss, exclusive breastmilk feeding, and the homozygous mutant of UGT1A1 211G>A were found to be risk factors for severe unconjugated hyperbilirubinemia. Clinical factors remain the most crucial and preventable determinants in managing severe unconjugated hyperbilirubinemia, with a minimal genetic contribution. The establishment of preconception care practices and the reinforcement of screening for the aforementioned risk factors are essential steps for preventing severe unconjugated hyperbilirubinemia.

Determination of the UGT1A1 polymorphism as guidance for irinotecan dose escalation in metastatic colorectal cancer treated with first-line bevacizumab and FOLFIRI (PURE FIST).

AIM: Uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) polymorphism plays a crucial role in the increased susceptibility of patients to irinotecan and its toxicity. This study is a multicenter, randomised clinical trial comparing the clinical outcomes and adverse events (AEs) in metastatic colorectal cancer (mCRC) patients treated with bevacizumab plus FOLFIRI with or without UGT1A1 genotyping and irinotecan dose escalation as the first-line therapy. METHODS: The control group received conventional biweekly FOLFIRI plus bevacizumab without UGT1A1 genotyping, whereas the study group received the same regimen with irinotecan dose escalation based on UGT1A1 genotyping. The primary end-point was progression-free survival (PFS), and secondary end-points were overall response rate (ORR), disease control rate (DCR), overall survival (OS), AEs and metastasectomy rate. RESULTS: Over a median follow-up of 26.0 months (IQR, 17.0-35.0 months), study group (n = 107) was superior to the control group (n = 106) in PFS, OS, ORR, DCR, and metastasectomy rate (all P < 0.05). Furthermore, there were no significant differences in AEs ≥ grade III between the two groups, even with the 1.36-fold increase in the relative dose intensity of irinotecan in the study group. Dose escalation of irinotecan, an independent factor of ORR (P < 0.001) and DCR (P = 0.006), improved PFS in mCRC patients with wild-type and mutant KRAS (P = 0.007 and P = 0.019, respectively). CONCLUSION: The current study revealed that mCRC patients, regardless of KRAS gene status, with UGT1A1 genotyping can tolerate escalated doses of irinotecan and potentially achieve a more favourable clinical outcome without significantly increased toxicities. CLINICAL TRIAL REGISTRATION: NCT02256800.

Uridine diphosphate glucuronosyl transferase 1A (UGT1A1) promoter polymorphism in young patients with sickle cell anaemia: report of the first cohort study from Nigeria.

BACKGROUND: (TA) n repeat sequence (rs8175347) of UGT1A1 gene promoter polymorphism is associated with serum bilirubin levels and gallstones among different sickle cell anaemia (SCA) populations. There are no data on UGT1A1 polymorphisms and their impact on Nigerian SCA patients. In this study, we determined the distribution of the UGT1A1 (TA) n genotypes among a group of young Nigerian SCA patients and healthy controls. In addition, the influence of UGT1A1 (TA) n genotypes on the laboratory and clinical events among the patients was determined. METHODS: The distribution of the UGT1A1 (TA) n genotypes among 101 young Nigerian SCA patients and 64 normal appropriate controls were determined and studied. The UGT1A1 (TA) n genotypes were further classified into subgroups and used to differentiate the clinical events and laboratory parameters of the patients. RESULTS: Four (TA) n alleles:(TA)5, 6, 7, and 8 were found. These were associated with 10 genotypes: TA5/5, 5/6, 5/7, 5/8, 6/6, 6/7, 6/8, 7/7, 7/8, 8/8. The normal (wild-type)-(TA) 6/6), low- (TA) 7/7, 7/8, 8/8), intermediate- (TA) 5/7, 5/8, 6/7, 6/8), and high-activity (TA) 5/5, 5/6,) genotypes were found in 24.8, 24.8, 41.5, and 8.9% patients and 20.3, 15.6, 61, and 3.1% controls respectively. The general genotype distribution of the patients and control group were not significantly different. There were significant differences in serum bilirubin and lactate dehydrogenase (LDH) of the patients when differentiated by the UGT1A1 (TA) n genotypes (p<0.05). Asymptomatic gallstones were found in 5.9% of patients and were significantly of the low-activity genotypes sub-group 5 (20%) vs 1(1.3%) p = 0.0033. Although, bilirubin and fetal hemoglobin (HbF) of patients with gallstones were significantly different from those without gallstone, only the serum bilirubin was associated with UGT1A1 (TA) n genotypes on multivariate analysis (p < 0.0001). CONCLUSION: This study highlights the contribution of UGT1A1 polymorphisms, a non-globin genetic factor, to the laboratory and clinical manifestations of young Nigerian SCA patients for the first time. It also shows that children with co-inheritance of low UGT1A1 (TA) n affinity genotypes may be at risk of gallstone, hence the need to follow them up.

UGT1A1 polymorphisms in rectal cancer associated with the efficacy and toxicity of preoperative chemoradiotherapy using irinotecan.

The purpose of the present study was to assess the efficacy and toxicity of preoperative chemoradiotherapy using irinotecan against locally advanced lower rectal cancer according to UDP-glucuronosyltransferase 1A1 (UGT1A1) polymorphisms. Between 2009 and 2016, 46 patients with resectable rectal cancer (T3-T4, N0-N2, M0) received preoperative chemoradiotherapy consisting of 80 mg/m2 per day tegafur/gimeracil/oteracil (S-1; days 1-5, 8-12, 22-26, and 29-33), 60 mg/m2 per day irinotecan (days 1, 8, 22, and 29), and 45 Gy radiation (1.8 Gy/day, 5 days per week for 5 weeks). Six to eight weeks after completing chemoradiotherapy, total mesorectal excision was carried out. Patients with UGT1A1 polymorphisms were divided into WT (n = 26), heterozygous (n = 15), and homozygous (n = 5) groups, the latter including double heterozygosities. We evaluated associations between clinical characteristics, including UGT1A1 polymorphisms, and chemoradiotherapy efficacy and toxicity. Incidence rates of grade 3+ neutropenia and diarrhea were 17.0% and 30.4%, respectively. Relative dose intensity was 89.3%. Pathological complete response rate (grade 3) was 26.1%, and the good response (grade 2/3) rate was 84.8%. UGT1A1 polymorphisms were significantly associated with neutropenia and pathological good responses, but not with diarrhea. UGT1A1 polymorphism was the only predictive factor for pathological good responses. Our results indicate that UGT1A1 polymorphism is a predictive factor to determine the clinical efficacy of preoperative chemoradiotherapy and hematological toxicity induced by chemoradiotherapy using irinotecan in locally advanced rectal cancer patients.

UGT1A1 polymorphisms with irinotecan-induced toxicities and treatment outcome in Asians with Lung Cancer: a meta-analysis.

Previous studies of irinotecan pharmacogenetics have shown that the UGT1A1*28 polymorphism has an effect on irinotecan (IRI)-induced toxicities in Caucasians. Yet compared with the UGT1A1*6 mutation, the UGT1A1*28 occurs at a much lower frequency in the Asians. Whether UGT1A1*6 and UGT1A1*28 are associated with IRI-induced neutropenia, diarrhea and IRI-based chemotherapy tumor response (TR) in Asians with lung cancer remains controversial. In this meta-analysis, we found a higher risk of neutropenia and diarrhea with IRI-based chemotherapy in Asians with lung cancer carrying the UGT1A1*6 polymorphism. However, UGT1A1*28 showed a weak correlation with diarrhea, but no significant correlation with neutropenia. Neither UGT1A1*6 nor UGT1A1*28 is associated with IRI-based chemotherapy TR. These data suggest that the UGT1A1*28 polymorphism may not be a suitable biomarker to predict IRI-induced toxicities and chemotherapy TR in Asians, while UGT1A*6 polymorphism is associated with a higher risk of IRI-induced neutropenia and diarrhea, but not IRI-based chemotherapy TR.

Clinical significance of UGT1A1 polymorphism and expression of ERCC1, BRCA1, TYMS, RRM1, TUBB3, STMN1 and TOP2A in gastric cancer.

BACKGROUND: Individualized therapeutic regimen is a recently intensively pursued approach for targeting diseases, in which the search for biomarkers was considered the first and most important. Thus, the goal of this study was to investigate whether the UGT1A1, ERCC1, BRCA1, TYMS, RRM1, TUBB3, STMN1 and TOP2A genes are underlying biomarkers for gastric cancer, which, to our knowledge, has not been performed. METHODS: Ninety-eight tissue specimens were collected from gastric cancer patients between May 2012 and March 2015. A multiplex branched DNA liquidchip technology was used for measuring the mRNA expressions of ERCC1, BRCA1, TYMS, RRM1, TUBB3, STMN1 and TOP2A. Direct sequencing was performed for determination of UGT1A1 polymorphisms. Furthermore, correlations between gene expressions, polymorphisms and clinicopathological characteristics were investigated. RESULTS: The expressions of TYMS, TUBB3 and STMN1 were significantly associated with the clinicopathological characteristics of age, gender and family history of gastric cancer, but not with differentiation, growth patterns, metastasis and TNM staging in patients with gastric cancer. No clinical characteristics were correlated with the expressions of ERCC1, BRCA1, RRM1 and TOP2A. Additionally, patients carrying G allele at -211 of UGT1A1 were predisposed to developing tubular adenocarcinoma, while individuals carrying 6TAA or G allele respectively at *28 or -3156 of UGT1A1 tended to have a local invasion. CONCLUSIONS: The UGT1A1 polymorphism may be useful to screen the risk population of gastric cancer, while TYMS, TUBB3 and STMN1 may be potential biomarkers for prognosis and chemotherapy guidance.

Case-controlled study on indirect hyperbilirubinemia in exclusively breast fed neonates and mutations of the bilirubin Uridine Diphosphate-Glucuronyl transferase gene 1A1.

OBJECTIVE: This study aims to investigate the association of neonatal indirect hyperbilirubinemia in exclusively breast-fed infants with UGT1A1 (Uridine Diphosphate-Glucuronyl transferase 1A1) polymorphism. METHODS: 50 neonates were classified into 2 groups: 1) 30 full term neonates with indirect hyperbilirubinemia (gestational age (GA) 39.5 ± 1.2 weeks); 2) 20 apparently healthy full-term neonates. Group 1 was further subdivided based on percentage of body weight lost: (A) less than 10%; (B) 10% or more. RESULTS: There was a statistically significant decrease in weight at sample collection and significant increase in indirect bilirubin level in patients group compared to control group, there was statistically significant difference as regard to genotype frequency [G/G, G/A, A/A], and allele frequency (A,G) between patients and control group. There was statistically significant increase in indirect bilirubin level in G/A - A/A genotypes. By comparing subgroup (A) and subgroup (B), there was statistically significant increase in total bilirubin level in subgroup (B). There was statistically high significant difference regarding genotype frequency (G/G, G/A, A/A) and allele frequency (G, A) between subgroup A and B. Multiple stepwise regression analysis was done using hyperbilirubinemia as a dependent factor and body weight loss, genotype (G/A) and allele (A) as independent factors. Body weight loss, genotype (G/A) and allele (A) was found to be significant independent predictors for hyperbilirubinemia. CONCLUSION: The results of the present study revealed that UGT1A1 polymorphism can be used as a novel predictor for neonatal hyperbilirubinemia in breast fed full term neonates.

Imatinib-induced hyperbilirubinemia with UGT1A1 (*28) promoter polymorphism: first case series in patients with gastrointestinal stromal tumor.

Imatinib, an orally administered protein-tyrosine kinase inhibitor (TKI) is indicated for the treatment of chronic myeloid leukemia (CML) and gastrointestinal stromal tumor (GIST). Severe hepatotoxicity associated with imatinib is rare, and relationship to polymorphism of uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) expression and related frequency of hyperbilirubinemia or toxicity are not well known. We present a case series patients who developed hyperbilirubinemia while on oral administration imatinib for treatment of GIST. Genetic testing for polymorphism of UGT1A1 showed the first patient to be homozygous for the UGT1A1 TA7 (*28) polymorphism and the second patient heterozygous for the UGT1A1 TA1 (*28) polymorphism. The first patient had to stop imatinib due to severe and persistent hyperbilirubenemia peaking >3 despite reducing imatininb to only 100 mg every other day while the second patient improved at this dose. Our case series represent the first data associating UGT1A1 polymorphism and imatinib in patients being treated for GIST. Given the prevalence of Gilbert's syndrome and the increasing use of imatinib, we encourage physicians to be aware of this possible toxicity as hepatotoxicity can be fatal if not managed in a timely fashion. This association is also timely due to recent FDA requirement for testing UGT1A1 polymorphism for nilotinib, another TKI.

Relationship between UGT1A1*6/*28 polymorphisms and severe toxicities in Chinese patients with pancreatic or biliary tract cancer treated with irinotecan-containing regimens.

PURPOSE: The aim of this retrospective study was to investigate the relationship between UGT1A1 polymorphisms and toxicities in Chinese patients with pancreatic or biliary tract cancer receiving irinotecan-containing regimens as the second- or third-line chemotherapy. PATIENTS AND METHODS: A total of 36 patients with unresectable pancreatic cancer and 12 patients with unresectable biliary tract cancer were included. Approximately 33 patients were treated with FOLFIRI regimen, a chemotherapy regimen, where FOL stands for folinic acid, F for fluorouracil, and IRI for irinotecan (irinotecan 180 mg/m(2) at day 1, CF 200 mg/m(2) at day 1-2, 5-FU 400 mg/m(2) at day 1-2, followed by continuous infusion of 5-FU 600 mg/m(2) for 22 hours at day 1-2, every 2 weeks). The other 15 patients were treated with irinotecan monotherapy (180 mg/m(2), every 2 weeks). UGT1A1*6/*28 polymorphisms were detected by direct sequencing. RESULTS: The frequencies of GG, GA, AA genotypes for UGT1A1*6 were 70.8% (n=34), 25.0% (n=12), and 4.2% (n=2), respectively. And those of TA6/TA6, TA6/TA7, TA7/TA7 for UGT1A1*28 were 79.2% (n=38), 18.8% (n=9), and 2.0% (n=1), respectively. A total of 22 patients (45.8%) had grade III-IV neutropenia, and six patients (12.5%) experienced grade III-IV diarrhea. The incidence of grade III-IV neutropenia in patients with UGT1A1*6 GA or AA genotype was 71.4%, which was significantly higher than that with GG genotype (35.3%, P=0.022). No relationship was found between grade III-IV neutropenia and UGT1A1*28 polymorphism. The statistical analysis between grade III-IV diarrhea and UGT1A1*6/*28 polymorphisms was not conducted in view of the limited number of patients. CONCLUSION: In Chinese patients with pancreatic or biliary tract cancer administered irinotecan-containing regimens, those with UGT1A1*6 variant may have a high risk of severe neutropenia.

The power of genes: a case of unusually severe systemic toxicity after localized hepatic chemoembolization with irinotecan-eluted microspheres for metastatic colon cancer.

OBJECTIVE: To report a case of systemic irinotecan toxicity following regional transarterial chemoembolization with drug-eluting beads loaded with irinotecan (DEBIRI-TACE) in a patient later found to have a homozygous mutation for UGT1A1*28. CASE SUMMARY: An 80-year-old woman presented with a cecal colon cancer with synchronous metastases to the liver. After resection of the primary tumor, the patient underwent DEBIRI-TACE with 100 mg of irinotecan to treat the residual disease in the liver. A week after this procedure, the patient developed grade 4 neutropenia, and later, alopecia. Eventually, it was found that the patient had a mutation of UDP glucuronosyltransferase 1 family polypeptide A1 (UGT1A1), which provided a reasonable explanation for the observed reaction. DISCUSSION: The toxic effects of irinotecan are well understood. Patients with genetic polymorphisms of the genes encoding for the enzyme UGT1A1 may have increased incidence of irinotecan-associated toxicities because of decreased clearance of the active metabolite SN38 via the glucuronidation pathway. To date, there have been limited publications describing systemic adverse events following TACE or DEBIRI-TACE and, based on a thorough literature search, none following these procedures in patients with UGT1A1 polymorphisms. Based on the scoring results of the Naranjo algorithm (7), we are confident in attributing the observed reaction to the patient's genetic polymorphism. CONCLUSION: Although genetic testing prior to the initiation of irinotecan therapy is not currently recommended, assessment of UGT1A1 polymorphism is warranted when severe adverse events typical of systemic therapy manifest following DEBIRI-TACE.