Clinical Pharmacogenetics Implementation Consortium guidelines for dihydropyrimidine dehydrogenase genotype and fluoropyrimidine dosing.
TL;DR: Evidence from the published literature supporting this association and dosing recommendations for fluoropyrimidines based on DPYD genotype are summarized and provided.
Abstract: The fluoropyrimidines are the mainstay chemotherapeutic agents for the treatment of many types of cancers. Detoxifying metabolism of fluoropyrimidines requires dihydropyrimidine dehydrogenase (DPD, encoded by the DPYD gene), and reduced or absent activity of this enzyme can result in severe, and sometimes fatal, toxicity. We summarize evidence from the published literature supporting this association and provide dosing recommendations for fluoropyrimidines based on DPYD genotype (updates at http://www.pharmgkb.org).
Citations
More filters
TL;DR: Current programs that use preemptive genotyping to optimize the pharmacotherapy of patients are discussed and key processes for implementation are highlighted, including clinical decision support.
Abstract: Although the field of pharmacogenetics has existed for decades, practioners have been slow to implement pharmacogenetic testing in clinical care. Numerous publications describe the barriers to clinical implementation of pharmacogenetics. Recently, several freely available resources have been developed to help address these barriers. In this review, we discuss current programs that use preemptive genotyping to optimize the pharmacotherapy of patients. Array-based preemptive testing includes a large number of relevant pharmacogenes that impact multiple high-risk drugs. Using a preemptive approach allows genotyping results to be available prior to any prescribing decision so that genomic variation may be considered as an inherent patient characteristic in the planning of therapy. This review describes the common elements among programs that have implemented preemptive genotyping and highlights key processes for implementation, including clinical decision support.
366 citations
Netherlands Cancer Institute1, University of Bern2, University of East Anglia3, St Thomas' Hospital4, First Faculty of Medicine, Charles University in Prague5, Bosch6, University of Tübingen7, Wellcome Trust Centre for Human Genetics8, Technische Universität München9, University of Amsterdam10, Utrecht University11
TL;DR: This systematic review and meta-analysis found that DPYD variants c.1679T>G and c.1236G>A/HapB3 are clinically relevant predictors of fluoropyrimidine-associated toxicity, and upfront screening for these variants, in addition to the established variants DPYD*2A andc.2846A>T, is recommended to improve the safety of patients with cancer treated with fluoropyridines.
Abstract: Summary Background The best-known cause of intolerance to fluoropyrimidines is dihydropyrimidine dehydrogenase (DPD) deficiency, which can result from deleterious polymorphisms in the gene encoding DPD ( DPYD ), including DPYD *2A and c.2846A>T. Three other variants— DPYD c.1679T>G, c.1236G>A/HapB3, and c.1601G>A—have been associated with DPD deficiency, but no definitive evidence for the clinical validity of these variants is available. The primary objective of this systematic review and meta-analysis was to assess the clinical validity of c.1679T>G, c.1236G>A/HapB3, and c.1601G>A as predictors of severe fluoropyrimidine-associated toxicity. Methods We did a systematic review of the literature published before Dec 17, 2014, to identify cohort studies investigating associations between DPYD c.1679T>G, c.1236G>A/HapB3, and c.1601G>A and severe (grade ≥3) fluoropyrimidine-associated toxicity in patients treated with fluoropyrimidines (fluorouracil, capecitabine, or tegafur-uracil as single agents, in combination with other anticancer drugs, or with radiotherapy). Individual patient data were retrieved and analysed in a multivariable analysis to obtain an adjusted relative risk (RR). Effect estimates were pooled by use of a random-effects meta-analysis. The threshold for significance was set at a p value of less than 0·0167 (Bonferroni correction). Findings 7365 patients from eight studies were included in the meta-analysis. DPYD c.1679T>G was significantly associated with fluoropyrimidine-associated toxicity (adjusted RR 4·40, 95% CI 2·08–9·30, p A/HapB3 (1·59, 1·29–1·97, p A and fluoropyrimidine-associated toxicity was not significant (adjusted RR 1·52, 95% CI 0·86–2·70, p=0·15). Analysis of individual types of toxicity showed consistent associations of c.1679T>G and c.1236G>A/HapB3 with gastrointestinal toxicity (adjusted RR 5·72, 95% CI 1·40–23·33, p=0·015; and 2·04, 1·49–2·78, p DPYD *2A and c.2846A>T were also significantly associated with severe fluoropyrimidine-associated toxicity (adjusted RR 2·85, 95% CI 1·75–4·62, p Interpretation DPYD variants c.1679T>G and c.1236G>A/HapB3 are clinically relevant predictors of fluoropyrimidine-associated toxicity. Upfront screening for these variants, in addition to the established variants DPYD *2A and c.2846A>T, is recommended to improve the safety of patients with cancer treated with fluoropyrimidines. Funding None.
260 citations
TL;DR: These data highlight three advantages of preemptive genotyping: the vast majority of patients carry at least one pharmacogenetic variant; data are available at the point of care; and there is a substantial reduction in testing burden compared with a reactive strategy.
Abstract: Since September 2010, more than 10,000 patients have undergone preemptive, panel-based pharmacogenomic testing through the Vanderbilt Pharmacogenomic Resource for Enhanced Decisions in Care and Treatment program. Analysis of the genetic data from the first 9,589 individuals reveals that the frequency of genetic variants is concordant with published allele frequencies. Based on five currently implemented drug-gene interactions, the multiplexed test identified one or more actionable variants in 91% of the genotyped patients and in 96% of African American patients. Using medication exposure data from electronic medical records, we compared a theoretical "reactive," prescription-triggered, serial single-gene testing strategy with our preemptive, multiplexed genotyping approach. Reactive genotyping would have generated 14,656 genetic tests. These data highlight three advantages of preemptive genotyping: (i) the vast majority of patients carry at least one pharmacogenetic variant; (ii) data are available at the point of care; and (iii) there is a substantial reduction in testing burden compared with a reactive strategy.
252 citations
TL;DR: The aim of this paper is to compare both initiatives and explore differences between the published guidelines, with the objective to achieve harmonization.
Abstract: Both the Clinical Pharmacogenetics Implementation Consortium (CPIC) and Dutch Pharmacogenetics Working Group provide therapeutic recommendations for well-known gene-drug pairs. Published recommendations show a high rate of concordance. However, as a result of different guideline development methods used by these two consortia, differences between the published guidelines exist. The aim of this paper is to compare both initiatives and explore these differences, with the objective to achieve harmonization.
186 citations
Cites background or methods from "Clinical Pharmacogenetics Implement..."
...DPYD The CPIC provides fluoropyrimidine dosing recommendations for normal/high, intermediate, and deficient dihydropyrimidine dehydrogenase activity phenotypes based on DPYD genotypes.(14) In contrast, the DPWG uses an activity-score (AS) to accommodate the increasing number of DPYD allelic variants and their difference in function (See Table 3)....
[...]
...In contrast, the CPIC mentions this variant without assigned status, similar to the IVS10-15TC variant.(14) CYP2D6 Both consortia classify the CYP2D6*36 allele as a variant allele; however, there is a difference in the interpretation of the functionality of this allele between the two consortia....
[...]
...The CPIC reports that there is a clear association of the *13 allele with reduced clearance of capecitabine and 5-fluorouracil in addition to evidence from case reports.(14) In contrast, the DPWG concludes that the evidence supporting a decreased activity of the *13 allele is limited and only described in case reports....
[...]
...DPYD 1 fluoropyrimidines As mentioned previously, the DPWG uses an AS for DPYD whereas the CPIC uses phenotypes of normal/high, intermediate, and deficient activity (soon to be changed to normal, intermediate, and poor metabolizers, respectively, in the next DPYD guideline update based on the results of the CPIC term standardization project).(14,51) The gene activity model scores alleles with a reduced function as 0....
[...]
TL;DR: Dose adjustment of 5-FU is feasible, and PK-based dosing can significantly improve clinical outcomes by reducing toxicities and improving efficacy, there is growing evidence to show.
Abstract: Purpose
For over 50 years, 5-FU has played a critical role in the systemic chemotherapy of cancer patients. 5-FU serves as the main backbone of combination chemotherapy for patients with colorectal cancer in both the adjuvant and metastatic disease settings. Herein, we review the current status of 5-FU therapeutic drug monitoring (TDM) and discuss its potential role in the clinical practice setting.
151 citations
References
More filters
TL;DR: Recommendations were developed for 53 drugs associated with genes coding for CYP2D6, CYP3A5, and HLA‐B*5701, and factor V Leiden (FVL).
Abstract: Currently, there are very few guidelines linking the results of pharmacogenetic tests to specific therapeutic recommendations. Therefore, the Royal Dutch Association for the Advancement of Pharmacy established the Pharmacogenetics Working Group with the objective of developing pharmacogenetics-based therapeutic (dose) recommendations. After systematic review of the literature, recommendations were developed for 53 drugs associated with genes coding for CYP2D6, CYP2C19, CYP2C9, thiopurine-S-methyltransferase (TPMT), dihydropyrimidine dehydrogenase (DPD), vitamin K epoxide reductase (VKORC1), uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1), HLA-B44, HLA-B*5701, CYP3A5, and factor V Leiden (FVL).
877 citations
TL;DR: The slow rate at which pharmacogenetic tests are being adopted in clinical practice is partly due to the lack of specific guidelines on how to adjust medications on the basis of the genetic test results.
Abstract: The slow rate at which pharmacogenetic tests are being adopted in clinical practice is partly due to the lack of specific guidelines on how to adjust medications on the basis of the genetic test results. One of the goals of the Clinical Pharmacogenetics Implementation Consortium (CPIC) of the National Institutes of Health’s Pharmacogenomics Research Network (http://www.pgrn.org) and the Pharmacogenomics Knowledge Base (PharmGKB, http://www.pharmgkb.org) is to provide peer-reviewed, updated, evidence-based, freely accessible guidelines for gene/drug pairs. These guidelines will facilitate the translation of pharmacogenomic knowledge from bench to bedside.
848 citations
TL;DR: 5-Fluorouracil, first introduced as a rationally synthesised anticancer agent 30 years ago, continues to be widely used in the management of several common malignancies including cancer of the colon, breast and skin.
Abstract: 5-Fluorouracil, first introduced as a rationally synthesised anticancer agent 30 years ago, continues to be widely used in the management of several common malignancies including cancer of the colon, breast and skin. This drug, an analogue of the naturally occurring pyrimidine uracil, is metabolised via the same metabolic pathways as uracil. Although several potential sites of antitumour activity have been identified, the precise mechanism of action and the extent to which each of these sites contributes to tumour or host cell toxicity remains unclear. Several assay methods are available to quantify 5-fluorouracil in serum, plasma and other biological fluids. Unfortunately, there is no evidence that plasma drug concentrations can predict antitumour effect or host cell toxicity. The recent development of clinically useful pharmacodynamic assays provides an attractive alternative to plasma drug concentrations, since these assays allow the detection of active metabolites of 5-fluorouracil in biopsied tumour or normal tissue. 5-Fluorouracil is poorly absorbed after oral administration, with erratic bioavailability. The parenteral preparation is the major dosage form, used intravenously (bolus or continuous infusion). Recently, studies have demonstrated the pharmacokinetic rationale and clinical feasibility of hepatic arterial infusion and intraperitoneal administration of 5-fluorouracil. In addition, 5-fluorouracil continues to be used in topical preparations for the treatment of malignant skin cancers. Following parenteral administration of 5-fluorouracil, there is rapid distribution of the drug and rapid elimination with an apparent terminal half-life of approximately 8 to 20 minutes. The rapid elimination is primarily due to swift catabolism of 5-fluorouracil in the liver. As with all drugs, caution should be used in administering 5-fluorouracil in various pathophysiological states. In general, however, there are no set recommendations for dose adjustment in the presence of renal or hepatic dysfunction. Drug interactions continue to be described with other antineoplastic drugs, as well as with other classes of agents.
847 citations
TL;DR: A markedly prolonged elimination half-life was observed with no evidence of FUra catabolites in plasma or cerebrospinal fluid and with 89.7% of the administered dose being excreted into the urine as unchanged FURA.
Abstract: Severe neurotoxicity due to 5-fluorouracil (FUra) has previously been described in a patient with familial pyrimidinemia. We now report the biochemical basis for both the pyrimidinemia and neurotoxicity in a patient we have recently studied. After administration of a "test" dose of FUra (25 mg/m2, 600 microCi[6-3H]FUra by intravenous bolus) to a patient who had previously developed neurotoxicity after FUra, a markedly prolonged elimination half-life (159 min) was observed with no evidence of FUra catabolites in plasma or cerebrospinal fluid and with 89.7% of the administered dose being excreted into the urine as unchanged FUra. Using a sensitive assay for dihydropyrimidine dehydrogenase in peripheral blood mononuclear cells, we demonstrated complete deficiency of enzyme activity in the patient and partial deficiency of enzyme activity in her father and children consistent with an autosomal recessive pattern of inheritance. Patients who are deficient in this enzyme are likely to develop severe toxicity after FUra administration.
485 citations
TL;DR: In this article, a prospective study on a large set of cancer patients in an attempt to evaluate the incidence of complete or partial dihydropyrimidine dehydrogenase deficiency as found in peripheral mononuclear cells (PMNC) was conducted.
Abstract: PURPOSEWe conducted a prospective study on a large set of cancer patients in an attempt to evaluate the incidence of complete or partial dihydropyrimidine dehydrogenase (DPD) deficiency as found in peripheral mononuclear cells (PMNC).PATIENTS AND METHODSOne hundred eighty-five unselected consecutive cancer patients were included. The population consisted of 152 men (mean age, 62.1 years; range, 35 to 90) and 33 women (mean age, 59.2 years; range, 36 to 77). Sixty-eight were head and neck patients treated by a 5-day continuous infusion of fluorouracil (FU; starting dose, 1 g/m2/d, with dose adaptation based on pharmacokinetics) for which DPD activity was measured 2 to 3 days before FU administration (94 cycles analyzed). PMNC-DPD activity was measured by a radio-enzymatic assay using carbon-14-FU.RESULTSDPD activity in the entire population showed a unimodal distribution, which globally fits a gaussian distribution. Mean and median DPD activity values were 0.222 and 0.211 nmol/min/mg protein, respectively ...
388 citations