Trial reportBritish journal of clinical pharmacology2015
The effect of atorvastatin treatment on serum oxysterol concentrations and cytochrome P450 3A4 activity.
Trial report in British journal of clinical pharmacology, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers, 1 of them a synthesis that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
13 citing papers in PubMed, 1 synthesis or guideline pooled it, 24 citations in OpenAlex.
- Statins for women with polycystic ovary syndrome not actively trying to conceive.The Cochrane database of systematic reviews · 2023Pooled it
- Trial
- Results of a Doravirine-Atorvastatin Drug-Drug Interaction Study.Antimicrobial agents and chemotherapy · 2017Trial
- Atorvastatin regulates hepatic transcriptome PXR dependently but distinct from pregnenolone 16α-carbonitrile and does not induce PXR-mediated liver steatosis.Archives of toxicology · 2026Article
- Is It Safe to Use Tranexamic Acid for Chronic Subdural Hematoma: A Systematic Review and Meta-Analysis.Asian journal of neurosurgery · 2025Review
- Article
- Does atorvastatin therapy change the anti-Xa activity in xabans-treated patients with atrial fibrillation?Pharmacology research & perspectives · 2021Observational
- Caffeine-clozapine interaction associated with severe toxicity and multiorgan system failure: a case report.BMC psychiatry · 2021Article
- 4Frontiers in pharmacology · 2020Article
- Onset timing of statin-induced musculoskeletal adverse events and concomitant drug-associated shift in onset timing of MAEs.Pharmacology research & perspectives · 2018Article
- Evaluation of 4β-Hydroxycholesterol and 25-Hydroxycholesterol as Endogenous Biomarkers of CYP3A4: Study with CYP3A-Humanized Mice.The AAPS journal · 2018Article
- Effect of Fenofibrate Medication on Renal Function.Korean journal of family medicine · 2017Article
- Comparative performance of oral midazolam clearance and plasma 4β-hydroxycholesterol to explain interindividual variability in tacrolimus clearance.British journal of clinical pharmacology · 2016Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
9 authors at 3 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
aimsAtorvastatin is known to both inhibit and induce the cytochrome P450 3A4 (CYP3A4) enzyme in vitro. Some clinical studies indicate that atorvastatin inhibits CYP3A4 but there are no well-controlled longer term studies that could evaluate the inducing effect of atorvastatin. We aimed to determine if atorvastatin induces or inhibits CYP3A4 activity as measured by the 4β-hydroxycholesterol to cholesterol ratio (4βHC : C).
methodsIn this randomized, double-blind, placebo-controlled 6 month study we evaluated the effects of atorvastatin 20 mg day(-1) (n = 15) and placebo (n = 14) on oxysterol concentrations and determined if atorvastatin induces or inhibits CYP3A4 activity as assessed by the 4βHC : C index. The respective 25-hydroxycholesterol and 5α,6α-epoxycholesterol ratios were used as negative controls.
resultsTreatment with atorvastatin decreased 4βHC and 5α,6α-epoxycholesterol concentrations by 40% and 23%, respectively. The mean 4βHC : C ratio decreased by 13% (0.214 ± 0.04 to 0.182 ± 0.04, P = 0.024, 95% confidence interval (CI) of the difference -0.0595, -0.00483) in the atorvastatin group while no significant change occurred in the placebo group. The difference in change of 4βHC : C between study arms was statistically significant (atorvastatin -0.032, placebo 0.0055, P = 0.020, 95% CI of the difference -0.069, -0.0067). The ratios of 25-hydroxycholesterol and 5α,6α-epoxycholesterol to cholesterol did not change.
conclusionsThe results establish atorvastatin as an inhibitor of CYP3A4 activity. Furthermore, 4βHC : C is a useful index of CYP3A4 activity, including the conditions with altered cholesterol concentrations.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.