scholarly journals Clinical Relevance of Novel Polymorphisms in the Dihydropyrimidine Dehydrogenase (DPYD) Gene in Patients with Severe Fluoropyrimidine Toxicity: A Spanish Case-Control Study

Pharmaceutics ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2036
Author(s):  
Paula Soria-Chacartegui ◽  
Gonzalo Villapalos-García ◽  
Luis A. López-Fernández ◽  
Marcos Navares-Gómez ◽  
Gina Mejía-Abril ◽  
...  

Among cancer patients treated with fluoropyrimidines, 10–40% develop severe toxicity. Polymorphism of the dihydropyrimidine dehydrogenase (DPYD) gene may reduce DPD function, the main enzyme responsible for the metabolism of fluoropyrimidines. This leads to drug accumulation and to an increased risk of toxicity. Routine genotyping of this gene, which usually includes DPYD *HapB3, *2A, *13 and c.2846A > T (D949V) variants, helps predict approximately 20–30% of toxicity cases. For DPD intermediate (IM) or poor (PM) metabolizers, a dose adjustment or drug switch is warranted to avoid toxicity, respectively. Societies such as the Spanish Society of Pharmacogenetics and Pharmacogenomics (SEFF), the Dutch Pharmacogenetics Working Group (DPWG) or the Clinical Pharmacogenetics Implementation Consortium (CPIC) and regulatory agencies (e.g., the Spanish Medicines Agency, AEMPS) already recommend DPYD routine genotyping. However, the predictive capacity of genotyping is currently still limited. This can be explained by the presence of unknown polymorphisms affecting the function of the enzyme. In this case-control work, 11 cases of severe fluoropyrimidine toxicity in patients who did not carry any of the four variants mentioned above were matched with 22 controls, who did not develop toxicity and did not carry any variant. The DPYD exome was sequenced (Sanger) in search of potentially pathogenic mutations. DPYD rs367619008 (c.187 A > G, p.Lys63Glu), rs200643089 (c.2324 T > G, p.Leu775Trp) and rs76387818 (c.1084G > A, p.Val362Ile) increased the percentage of explained toxicities to 38–48%. Moreover, there was an intronic variant considered potentially pathogenic: rs944174134 (c.322-63G > A). Further studies are needed to confirm its clinical relevance. The remaining variants were considered non-pathogenic.

2020 ◽  
Vol 10 (3) ◽  
pp. 113 ◽  
Author(s):  
Valeria Conti ◽  
Emanuela De Bellis ◽  
Valentina Manzo ◽  
Francesco Sabbatino ◽  
Francesco Iannello ◽  
...  

Fluoropyrimidines (FP) are mainly metabolised by dihydropyrimidine dehydrogenase (DPD), encoded by the DPYD gene. FP pharmacogenetics, including four DPYD polymorphisms (DPYD-PGx), is recommended to tailor the FP-based chemotherapy. These polymorphisms increase the risk of severe toxicity; thus, the DPYD-PGx should be performed prior to starting FP. Other factors influence FP safety, therefore phenotyping methods, such as the measurement of 5-fluorouracil (5-FU) clearance and DPD activity, could complement the DPYD-PGx. We describe a case series of patients in whom we performed DPYD-PGx (by real-time PCR), 5-FU clearance and a dihydrouracil/uracil ratio (as the phenotyping analysis) and a continuous clinical monitoring. Patients who had already experienced severe toxicity were then identified as carriers of DPYD variants. The plasmatic dihydrouracil/uracil ratio (by high-performance liquid chromatography (HPLC)) ranged between 1.77 and 7.38. 5-FU clearance (by ultra-HPLC with tandem mass spectrometry) was measured in 3/11 patients. In one of them, it reduced after the 5-FU dosage was halved; in the other case, it remained high despite a drastic dosage reduction. Moreover, we performed a systematic review on genotyping/phenotyping combinations used as predictive factors of FP safety. Measuring the plasmatic 5-FU clearance and/or dihydrouracil/uracil (UH2/U) ratio could improve the predictive potential of DPYD-PGx. The upfront DPYD-PGx combined with clinical monitoring and feasible phenotyping method is essential to optimising FP-based chemotherapy.


2013 ◽  
Vol 31 (4_suppl) ◽  
pp. 447-447
Author(s):  
Jennifer Saam ◽  
Karla Bowles ◽  
Laurie Korst ◽  
Kendel Kline ◽  
Benjamin Roa ◽  
...  

447 Background: Dihydropyrimidine dehydrogenase (DPYD) is the major enzyme that metabolizes 5-Fluoruracil (5-FU), a component of many chemotherapy regimens. Patients with a DPYD gene mutation have higher 5-FU plasma levels, leading to a 50-60% risk of a grade 3-4 toxicity. DPYD mutations have an estimated prevalence of 3-5% in the general population, but full sequencing is rarely performed in published studies. Analyses of the largest set of full DPYD gene sequencing test results from a commercial laboratory database are presented. Methods: A set of 3,083 patients was analyzed. Patient demographics (age, gender, ethnicity) and pre-test grade 3-4 toxicity status (none, 5-FU related, other) were obtained from the test request form. Descriptive analyses were performed to estimate mutation prevalence overall, and by toxicity and ancestry classifications, as well as to characterize mutations of interest. A subset of 24 patients tested for DPYD mutations in response to high 5-FU exposure levels was also analyzed. Results: The overall DPYD mutation prevalence was 7.3%. Mutations were present in 4.7% and 10.3% of patients experiencing none and at least one 5-FU related toxicity pre-test, respectively. Among patients with toxicities pre-test, the prevalence increased from 7.8% to 31.6% for those experiencing a single to all four toxicity types. Among 5-FU related toxicities, mutation prevalence was highest (18.5%) for hematopoietic events. The previously reported founder mutation IVS14+1G>A had a relative prevalence 42.7%, but 30.9% of these mutations were seen in patients not reporting a Western/Northern European ancestry. Among the subset of patients with high 5-FU exposure levels, 29% had a DPYD mutation showing a genetic causality. Conclusions: 5-FU in chemotherapy regimens remains widespread, yet DPYD gene testing utilization remains minimal. Most testing occurs post-treatment in response to a severe toxicity rather than pre-treatment, which would permit physicians to adapt treatment and reduce toxicity risk. Compared to previous studies, this study using full sequencing data from 3083 patients provides robust estimates of DPYD mutation prevalence and helps characterize DPYD mutations of particular interest.


2008 ◽  
Vol 26 (13) ◽  
pp. 2131-2138 ◽  
Author(s):  
Matthias Schwab ◽  
Ulrich M. Zanger ◽  
Claudia Marx ◽  
Elke Schaeffeler ◽  
Kathrin Klein ◽  
...  

Purpose To assess the predictive value of polymorphisms in dihydropyrimidine dehydrogenase (DPYD ), thymidylate synthase (TYMS ), and methylene tetrahydrofolate reductase (MTHFR ) and of nongenetic factors for severe leukopenia, diarrhea, and mucositis related to fluorouracil (FU) treatment. Patients and Methods A multicenter prospective clinical trial included 683 patients with cancer treated with FU monotherapy. Toxicity was documented according to World Health Organization grades. DPYD, TYMS, and MTHFR genotypes were determined, and DPYD was resequenced in patients with severe toxicity. Results Grade 3 to 4 toxicity occurred in 16.1% of patients. The sensitivity of DPYD*2A genotyping for overall toxicity was 5.5% (95%CI, 0.02 to 0.11), with a positive predictive value of 0.46 (95% CI, 0.19 to 0.75; P = .01). Inclusion of additional DPYD variants improved prediction only marginally. Analysis according to toxicity type revealed significant association of DPYD with mucositis and leukopenia, whereas TYMS was associated with diarrhea. Genotype, female sex, mode of FU administration, and modulation by folinic acid were identified as independent risk factors by multivariable analysis. A previously unrecognized significant interaction was found between sex and DPYD, which resulted in an odds ratio for toxicity of 41.8 for male patients (95% CI, 9.2 to 190; P < .0001) but only 1.33 (95% CI, 0.34 to 5.2) in female patients. Homozygosity for the TYMS enhancer region double repeat allele increased risk for toxicity 1.6-fold (95% CI, 1.08 to 2.22; P = .02). Conclusion DPYD, TYMS, and MTHFR play a limited role for FU related toxicity but a pronounced DPYD gene/sex-interaction increases prediction rate for male patients. Toxicity risk assessment should include sex, mode of administration, and folinic acid as additional predictive factors.


2021 ◽  
pp. 1-8
Author(s):  
Regina Sá ◽  
Tiago Pinho-Bandeira ◽  
Guilherme Queiroz ◽  
Joana Matos ◽  
João Duarte Ferreira ◽  
...  

<b><i>Background:</i></b> Ovar was the first Portuguese municipality to declare active community transmission of SARS-CoV-2, with total lockdown decreed on March 17, 2020. This context provided conditions for a large-scale testing strategy, allowing a referral system considering other symptoms besides the ones that were part of the case definition (fever, cough, and dyspnea). This study aims to identify other symptoms associated with COVID-19 since it may clarify the pre-test probability of the occurrence of the disease. <b><i>Methods:</i></b> This case-control study uses primary care registers between March 29 and May 10, 2020 in Ovar municipality. Pre-test clinical and exposure-risk characteristics, reported by physicians, were collected through a form, and linked with their laboratory result. <b><i>Results:</i></b> The study population included a total of 919 patients, of whom 226 (24.6%) were COVID-19 cases and 693 were negative for SARS-CoV-2. Only 27.1% of the patients reporting contact with a confirmed or suspected case tested positive. In the multivariate analysis, statistical significance was obtained for headaches (OR 0.558), odynophagia (OR 0.273), anosmia (OR 2.360), and other symptoms (OR 2.157). The interaction of anosmia and odynophagia appeared as possibly relevant with a borderline statistically significant OR of 3.375. <b><i>Conclusion:</i></b> COVID-19 has a wide range of symptoms. Of the myriad described, the present study highlights anosmia itself and calls for additional studies on the interaction between anosmia and odynophagia. Headaches and odynophagia by themselves are not associated with an increased risk for the disease. These findings may help clinicians in deciding when to test, especially when other diseases with similar symptoms are more prevalent, namely in winter.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Bojing Liu ◽  
Arvid Sjölander ◽  
Nancy L. Pedersen ◽  
Jonas F. Ludvigsson ◽  
Honglei Chen ◽  
...  

AbstractTo examine whether irritable bowel syndrome (IBS) was related to the future risk of Parkinson’s disease (PD), we conducted a nested case-control study in the Swedish total population including 56,564 PD cases identified from the Swedish Patient Register and 30 controls per case individually matched by sex and year of birth. Odds ratios (ORs) with 95% confidence intervals (CIs) for having a prior diagnosis of IBS were estimated using conditional logistic regression. We furthermore conducted a cohort study using the Swedish Twin Registry following 3046 IBS patients identified by self-reported abdominal symptoms and 41,179 non-IBS individuals. Through Cox proportional hazard models, we estimated hazard ratios (HRs) and 95% CIs for PD risk. In the nested case-control study, 253 (0.4%) PD cases and 5204 (0.3%) controls had a previous IBS diagnosis. IBS diagnosis was associated with a 44% higher risk of PD (OR = 1.44, 95% CI 1.27–1.63). Temporal relationship analyses showed 53% and 38% increased risk of PD more than 5 and 10 years after IBS diagnosis, respectively. In the cohort analysis based on the Swedish Twin Registry, there was no statistically significantly increased risk of PD related to IBS (HR = 1.25, 95% CI = 0.87–1.81). Our results suggest a higher risk of PD diagnosis after IBS. These results provide additional evidence supporting the importance of the gut–brain axis in PD.


2021 ◽  
Vol 58 (5) ◽  
pp. 567-576
Author(s):  
Ronald G. Munger ◽  
Rajarajeswari Kuppuswamy ◽  
Jyotsna Murthy ◽  
Kalpana Balakrishnan ◽  
Gurusamy Thangavel ◽  
...  

Background and Objective: The causal role of maternal nutrition in orofacial clefts is uncertain. We tested hypotheses that low maternal vitamin B12 and low folate status are each associated with an increased risk of isolated cleft lip with or without cleft palate (CL±P) in a case–control study in Tamil Nadu state, India. Methods: Case-mothers of CL±P children (n = 47) and control-mothers of unaffected children (n = 50) were recruited an average of 1.4 years after birth of the index child and plasma vitamin B12, methylmalonic acid (MMA), total homocysteine (tHcy), and folate were measured at that time. Logistic regression analyses estimated associations between nutrient biomarkers and case–control status. Results: Odds ratios (ORs) contrasting biomarker levels showed associations between case-mothers and low versus high plasma vitamin B12 (OR = 2.48, 95% CI, 1.02-6.01) and high versus low plasma MMA, an indicator of poor B12 status (OR = 3.65 95% CI, 1.21-11.05). Case–control status was not consistently associated with folate or tHcy levels. Low vitamin B12 status, when defined by a combination of both plasma vitamin B12 and MMA levels, had an even stronger association with case-mothers (OR = 6.54, 95% CI, 1.33-32.09). Conclusions: Mothers of CL±P children in southern India were 6.5 times more likely to have poor vitamin B12 status, defined by multiple biomarkers, compared to control-mothers. Further studies in populations with diverse nutritional backgrounds are required to determine whether poor maternal vitamin B12 or folate levels or their interactions are causally related to CL±P.


2021 ◽  
Vol 14 ◽  
pp. 175628482110244
Author(s):  
Muhammad Wasif M. Saif ◽  
Ruchi Hamal ◽  
Nauman Siddiqui ◽  
Antonia Maloney ◽  
Melissa Smith

Background: 5-fluorouracil (5-FU) and mitomycin-C (MMC) with radiotherapy (RT) remain an established treatment for patients with anal cancer (AC). Genetic mutations in two major metabolizing enzymes for 5-FU; dihydropyrimidine dehydrogenase ( DPYD and thymidylate synthetase ( TYMS), have been associated with clinical response and toxicity. However, their place in the treatment of AC remains undetermined. Methods: We retrospectively reviewed 21 patients with AC, including T2-4, N0-1, M0 or T1-4, N2-3, and M0 treated between 2012 and 2018. All patients were treated with 5-FU 1,000 mg/m2/day via continuous intravenous (IV) infusion 1–4 and 29–32, MMC 10 mg/m2 IV bolus days 1 and 29 plus RT. Patients who developed ⩾3 grade toxicities were tested for the DPYD and TYMS genes. Treatment was either modified with reduced doses or changed to MMC 10 mg/m2 day 1 and 29 with cisplatin 25 mg/m2/week plus RT. Toxicities and responses were collected. Results: Six out of 21 patients who developed ⩾3 grade toxicities including pancytopenia, neutropenia, thrombocytopenia, mucositis, nausea, rash, and nephritis were found to have genetic mutations: TYMS 2RG/3RC ( n = 2), 3RG/3RC ( n = 1), 2R/2R ( n = 2), T YMS 3′UTR del/Ins ( n = 2), and DPYD c.2864A > T heterozygous ( n = 1). Two patients received 5-FU at a 50% reduced dose on days 29–32; one patient refused to receive 5-FU (continued with MMC and RT); one patient received only radiation therapy due to persistent pancytopenia despite the use of growth factors; two patients received an alternative regimen consisting of MMC 10 mg/m2 on day 29 with cisplatin (CDDP) 25 mg/m2/week plus RT; and two patients received cisplatin/MMC with RT from the beginning as they were prospectively detected to have TYMS abnormalities prior to dosing the chemotherapy. These patients tolerated treatment very well with only grade 2 toxicities. All the patients (4/4) on cisplatin/MMC achieved clinical complete response (cCR), while four patients (4/15) on 5-FU/MMC reached cCR at the first assessment. Radiological response showed complete response at the end of 24 weeks assessment. Conclusions: Molecular testing for DPYD and TYMS genes can allow us to identify patients who are most likely to respond or face severe toxicity to 5-FU in a potentially curable cancer. Combining radiation with CDDP with MMC in patients with AC is feasible. A prospective study based on pharmacogenetic testing comparing MMC/cisplatin with MMC/5-FU is indicated in patients with AC.


BMC Medicine ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Paul M. McKeigue ◽  
◽  
Sharon Kennedy ◽  
Amanda Weir ◽  
Jen Bishop ◽  
...  

Abstract Background The objective of this study was to investigate the relation of severe COVID-19 to prior drug prescribing. Methods Severe cases were defined by entry to critical care or fatal outcome. For this matched case-control study (REACT-SCOT), all 4251 cases of severe COVID-19 in Scotland since the start of the epidemic were matched for age, sex and primary care practice to 36,738 controls from the population register. Records were linked to hospital discharges since June 2015 and dispensed prescriptions issued in primary care during the last 240 days. Results Severe COVID-19 was strongly associated with the number of non-cardiovascular drug classes dispensed. This association was strongest in those not resident in a care home, in whom the rate ratio (95% CI) associated with dispensing of 12 or more drug classes versus none was 10.8 (8.8, 13.3), and in those without any of the conditions designated as conferring increased risk of COVID-19. Of 17 drug classes postulated at the start of the epidemic to be “medications compromising COVID”, all were associated with increased risk of severe COVID-19 and these associations were present in those without any of the designated risk conditions. The fraction of cases in the population attributable to exposure to these drug classes was 38%. The largest effect was for antipsychotic agents: rate ratio 4.18 (3.42, 5.11). Other drug classes with large effects included proton pump inhibitors (rate ratio 2.20 (1.72, 2.83) for = 2 defined daily doses/day), opioids (3.66 (2.68, 5.01) for = 50 mg morphine equivalent/day) and gabapentinoids. These associations persisted after adjusting for covariates and were stronger with recent than with non-recent exposure. Conclusions Severe COVID-19 is associated with polypharmacy and with drugs that cause sedation, respiratory depression, or dyskinesia; have anticholinergic effects; or affect the gastrointestinal system. These associations are not easily explained by co-morbidity. Measures to reduce the burden of mortality and morbidity from COVID-19 should include reinforcing existing guidance on reducing overprescribing of these drug classes and limiting inappropriate polypharmacy. Registration ENCEPP number https://EUPAS35558


Sign in / Sign up

Export Citation Format

Share Document