SynthesisEuropean journal of clinical pharmacology2020
Influence of CYP2C9 and CYP2A6 on plasma concentrations of valproic acid: a meta-analysis.
Synthesis in European journal of clinical pharmacology, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 10 papers, 1 of them a synthesis that pooled it.
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
10 citing papers in PubMed, 1 synthesis or guideline pooled it, 19 citations in OpenAlex.
- Pharmacogenetic Variants and Plasma Concentrations of Antiseizure Drugs: A Systematic Review and Meta-Analysis.JAMA network open · 2024Pooled it
- Determinants and Machine Learning Prediction of Subtherapeutic Sodium Valproate Concentrations in Epilepsy Management in Xinjiang, China.European journal of drug metabolism and pharmacokinetics · 2026Article
- Sodium Valproate-Associated Thrombocytopenia in Antiepileptic Drug Polypharmacy: A Case Report and Review of the Literature.The American journal of case reports · 2025Review
- Ethnic Aspects of Valproic Acid P-Oxidation.Biomedicines · 2024Review
- The role of candidate pharmacogenetic variants in determining valproic acid efficacy, toxicity and concentrations in patients with epilepsy.Frontiers in pharmacology · 2024Article
- Pre-treatment risk predictors of valproic acid-induced dyslipidemia in pediatric patients with epilepsy.Frontiers in pharmacology · 2024Article
- Evaluation ofPharmacogenomics and personalized medicine · 2024Article
- Therapeutic and Toxic Effects of Valproic Acid Metabolites.Metabolites · 2023Review
- Pharmacogenetics of Carbamazepine and Valproate: Focus on Polymorphisms of Drug Metabolizing Enzymes and Transporters.Pharmaceuticals (Basel, Switzerland) · 2021Review
- Research Progress of Pharmacogenomics in Drug-Induced Liver Injury.Frontiers in pharmacology · 2021Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
6 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
purposeCytochrome P450 (CYP) is involved in the metabolism of valproic acid (VPA). Specifically, CYP2C9 and CYP2A6 are the main enzymes responsible for VPA metabolism. However, the correlation between plasma VPA concentrations and CYP2C9 and CYP2A6 gene variations is uncertain. This meta-analysis aimed to investigate the relationship between CYP2C9 and CYP2A6 variants and plasma concentrations of VPA.
methodsThe PubMed, Web of Science, and EMBASE databases were searched for qualifying studies published until July 2019. Cohort studies that included standardized plasma VPA concentrations and CYP2C9 and CYP2A6 genotypes were reviewed. The mean difference and 95% confidence intervals (CIs) were evaluated to assess the strength of the relationship. Data analysis was performed using Review Manager (version 5.3) and RStudio (version 3.6).
resultsIn total, we analyzed data from six studies involving 807 patients. We found that CYP2C9*3 was associated with standardized plasma VPA concentration; *3 allele carriers had a 0.70-μg/mL higher concentration per mg/kg than non-carriers (95% CI 0.25, 1.15; P = 0.002). We also found a significant association between the CYP2A6*4 and standardized trough VPA concentration; patients with the *4 allele had a 0.48-μg/mL higher concentration per mg/kg than patients without the *4 allele (95% CI 0.10, 0.86; P = 0.01).
conclusionThis meta-analysis demonstrated that CYP2C9*3 and CYP2A6*4 genetic variants affect plasma VPA concentrations. For epilepsy patients with these genotypes, dose adjustment may be necessary to ensure VPA's therapeutic effect.
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