cytochrome P450 family 3 subfamily A member 4

Overview

Cytochrome P450 family 3 subfamily A member 4, commonly abbreviated CYP3A4, is a major human drug-metabolizing enzyme in the cytochrome P450 superfamily. It plays a central role in the oxidative metabolism of a wide range of endogenous compounds and xenobiotics, including many clinically used drugs. As a hepatic and intestinal enzyme, CYP3A4 is one of the most important determinants of drug clearance, interindividual variability in exposure, and susceptibility to drug–drug interactions.

Functionally, CYP3A4 operates within the broader cytochrome P450 catalytic system and requires electrons supplied by P450 oxidoreductase (POR) for its catalytic cycle. In biomedical research, CYP3A4 is frequently used as a marker of metabolic capacity and as a key target in studies of pharmacokinetics, enzyme inhibition, and drug safety. It is also closely studied alongside related enzymes such as CYP3A5, CYP2C19, CYP2B6, and CYP1A2, as well as transporters such as ABCB1, because these proteins collectively shape drug disposition and therapeutic response.

Focus of Latest Publications

Recent studies have continued to emphasize CYP3A4 as a central determinant of drug disposition and interaction liability across multiple therapeutic areas.

A population-based study on opioid toxicity examined concomitant use of macrolide antibiotics with fentanyl, hydromorphone, or oxycodone. The study context highlighted that these opioids are metabolized by CYP3A4, supporting the mechanistic basis for concern that CYP3A4 inhibition by macrolides could increase opioid exposure and toxicity risk. This reinforces the enzyme’s role in clinically important drug–drug interactions involving analgesics.

Several studies focused on CYP3A4-mediated metabolism of targeted anticancer and kinase-inhibitor therapies. In work on vebreltinib, in vitro data indicated that the drug is primarily metabolized by CYP3A4, and the study was designed to characterize interaction potential with strong CYP3A4 modulators such as rifampin and itraconazole in healthy participants. Similarly, golvatinib was found to be metabolized principally by CYP3A4, and donafenib N-oxide formation was identified as being catalyzed primarily by CYP3A4 in phenotyping assays using chemical inhibitors and recombinant enzymes. These findings place CYP3A4 at the center of metabolic liability for several newer oncology agents.

CYP3A4 was also examined in relation to established and emerging therapies with known interaction sensitivity. venetoclax, described in the publication context as a selective BCL-2 inhibitor predominantly metabolized by CYP3A4, was studied in the setting of interactions with posaconazole and voriconazole, both strong azole inhibitors. Another study evaluated siponimod using clinical data and updated physiologically based pharmacokinetic modeling, including the impact of the CYP3A4 inhibitor clarithromycin on siponimod metabolism. In a separate clinical pharmacology study, midazolam was used as a sensitive CYP3A4 substrate in healthy participants to assess potential interactions with bemnifosbuvir.

Natural products and herbal medicines were also investigated for CYP3A4 effects. A study of Tinospora crispa stem extracts and borapetoside C assessed CYP3A4 inhibitory activity in a HepaRG cell model, a validated system for CYP450 inhibition testing. Another systems pharmacology study of sanguinarine identified CYP1A2, CYP2C19, CYP3A4, and CYP2D6 as principal Phase I enzymes involved in its metabolism. In addition, vindoline, derived from Catharanthus roseus, was reported to exhibit minimal CYP3A4 inhibition and no detectable acute toxicity in vivo, suggesting a favorable interaction profile in the context of anticancer research.

CYP3A4 also appeared in pharmacogenomic and biomarker-oriented research. A candidate-gene study in a Japanese cohort examined CYP3A-related SNPs using the 4β-hydroxycholesterol/cholesterol ratio as a biomarker, with CYP3A4 and CYP3A5 described as major drug-metabolizing enzymes requiring electrons supplied by POR. Another study on clopidogrel resistance in recurrent ischemic stroke genotyped patients for multiple genes including CYP3A4, CYP3A5, CYP2C19, CYP2C9, CYP2B6, CYP1A2, ABCB1, and CES1A1, reflecting the broader interest in CYP3A4 within combined pharmacogenetic models.

Beyond human clinical and translational studies, CYP3A4 was used as a marker of hepatic metabolic competence in engineered liver systems. An organoid-based study reported elevated expression of CYP3A4, CYP2C9, and CYP1A2 in hiPSC-derived liver organoids, indicating maturation toward a drug-metabolizing phenotype. Such systems are relevant for toxicity screening and metabolism studies, especially when evaluating compounds with CYP3A4 liability.

Collectively, these publications show CYP3A4 as a recurring focus in studies of opioid safety, antifungal and antibiotic interactions, oncology drug metabolism, herbal product assessment, pharmacogenomics, and liver-model development. The enzyme’s broad substrate range and susceptibility to inhibition make it a key target in both mechanistic and clinical pharmacology.

Key Publications

• NEWApr Opioid Toxicity Following Concomitant Use of Macrolide Antibiotics with Fentanyl, Hydromorphone, or Oxycodone: A Population-Based Study. (Clinical pharmacology and therapeutics, 2026, PMID 41944476): "Fentanyl, hydromorphone, and oxycodone are metabolized by cytochrome P450 3A4 (CYP3A4)."
• NEWJul PBPK Modeling and Clinical Data Reveal Reduced Impact of CYP3A4 and CYP2C9 Inhibitors on Elimination of Siponimod. (Clinical and translational science, 2026, PMID 42364973): "The presented work includes clinical data describing the impact of the CYP3A4 inhibitor clarithromycin on siponimod metabolism and the results of updated physiologically based pharmacokinetic (PBPK) modeling."
• Jul Drug Interactions of Vebreltinib, a Novel Type I c-Met Inhibitor, Coadministration With Rifampin or Itraconazole in Healthy Participants. (Clinical and translational science, 2026, PMID 42348314): "As in vitro studies indicate that vebreltinib is primarily metabolized via cytochrome P450 (CYP) 3A4, this study aimed to characterize the drug-drug interaction (DDI) potential of vebreltinib with strong CYP3A4 modulators."
• Jun Candidate-gene-based study of CYP3A-related single-nucleotide polymorphisms using 4β-hydroxycholesterol/cholesterol ratio as biomarker in a Japanese cohort. (European journal of clinical pharmacology, 2026, PMID 42319470): "CYP3A4 and CYP3A5 are major drug‐metabolizing enzymes that require electrons supplied by P450 oxidoreductase (POR) for catalytic cycle."
• Jun Vindoline, a vinca alkaloid derived from Catharanthus roseus, targets ABCB1 to overcome docetaxel resistance in prostate cancer. (Biochemical and biophysical research communications, 2026, PMID 42000630): "Notably, vindoline exhibited minimal CYP3A4 inhibition and no detectable acute toxicity in vivo."
• Jun The association of ABCB1, CYP2C19 and CYP2C9 combined activity with clopidogrel resistance in patients with recurrent ischemic stroke. (The pharmacogenomics journal, 2026, PMID 42303966): "Patients were genotyped for CYP2C19, CYP2C9, CYP2B6, CYP3A4, CYP3A5, CYP1A2, ABCB1 and CES1A1."
• Jun Integrated systems pharmacology-based exploration of sanguinarine: Comprehensive metabolite identification, enzyme mapping, and network analysis. (Bioorganic chemistry, 2026, PMID 41844053): "Recombinant enzyme phenotyping revealed CYP1A2, 2C19, 3A4 and 2D6 as the principal Phase I enzymes."
• Jun Contribution to the quality and safety assessment of traditional herbal remedy Tinospora crispa stem using phytochemical analyses and CYP3A4 inhibition assay in HepaRG cell model. (Toxicon : official journal of the International Society on Toxinology, 2026, PMID 41850439): "The CYP3A4 inhibitory activities of the methanol extracts and of borapetoside C were measured in a HepaRG cell model, which is a validated model for studying CYP450 inhibitory effects."
• Jun Effects of Cytochrome P450 enzymes and drug-drug interaction on donafenib metabolism: in vivo, in vitro and in silico. (Bioorganic chemistry, 2026, PMID 41687527): "In vitro phenotyping assays using chemical inhibitors and recombinant CYP enzymes identified CYP3A4 as the primary enzyme catalyzing donafenib N-oxide formation."
• Jun An Effective and Systematic Strategy for Metabolic Profiling of Golvatinib In Vitro by Combining UHPLC-MS/MS and UHPLC-Q-Orbitrap-HRMS. (Journal of separation science, 2026, PMID 42210592): "Further study demonstrated that CYP3A4 was the principal enzyme involved in metabolizing golvatinib."