Cytochrome P450 activity in rheumatoid arthritis patients during continuous IL-6 receptor antagonist therapy.

BACKGROUND: Inflammation suppresses cytochrome P450 (CYP) enzyme activity, and single-dose interleukin 6 receptor antagonists (anti-IL-6R) reverse this effect. Here, we assess the impact of continuous anti-IL-6R therapy in patients with rheumatoid arthritis. METHODS: In a clinical pharmacokinetic trial, the Basel cocktail was administered before and after 3 and 12 weeks of anti-IL-6R therapy to assess CYP enzyme activity (registered in the ClinicalTrials.gov database (identifier NCT04842981) on April 13th, 2021). In a retrospective study, the 4ß-hydroxycholesterol/cholesterol ratio was measured as a biomarker for CYP3A4 activity before and after 3 and 6 months of anti-IL-6R therapy. The control group was patients initiating a tumor necrosis factor alfa (TNF-α) inhibitor. RESULTS: In the clinical pharmacokinetic trial (n = 3), midazolam metabolic ratio (CYP3A4) was inconclusive due to the limited sample size. Midazolam AUC and Cmax indicate a weak impact on CYP3A4 activity after 3 weeks of anti-IL-6R therapy compared to baseline (AUC geometric mean ratio (GMR): 0.80, 95% CI: 0.64-0.99 and Cmax GMR: 0.58, 95% CI: 0.37-0.91), which returns to baseline levels after 12 weeks of therapy (AUC GMR 1.02, 95% CI: 0.72-1.46 and Cmax GMR 1.03, 95% CI 0.72-1.47). No effect on the 4ß-hydroxycholesterol/cholesterol ratio was observed in the retrospective study. CONCLUSION: Based on sparse data from three patients, continuous anti-IL-6R therapy seems to cause an acute but transient increase in CYP3A4 activity in rheumatoid arthritis patients, which may be due to a normalization of the inflammation-suppressed CYP activity. Further studies are warranted to understand the mechanism behind this putative transient effect. Trial registration Registered in the ClinicalTrials.gov database (identifier NCT04842981) on April 13th, 2021.

Multifactorial intervention to prevent cardiovascular disease in patients with early rheumatoid arthritis: protocol for a multicentre randomised controlled trial.

INTRODUCTION: Cardiovascular morbidity is a major burden in patients with rheumatoid arthritis (RA). In this study, we compare the effect of a targeted, intensified, multifactorial intervention with that of conventional treatment of modifiable risk factors for cardiovascular disease (CVD) in patients with early RA fulfilling the 2010 American College of Rheumatology European League Against Rheumatism (ACR/EULAR) criteria. METHODS AND ANALYSIS: The study is a prospective, randomised, open label trial with blinded end point assessment and balanced randomisation (1:1) conducted in 10 outpatient clinics in Denmark. The primary end point after 5 years of follow-up is a composite of death from cardiovascular causes, non-fatal myocardial infarction, non-fatal stroke and cardiac revascularisation. Secondary outcomes are: the proportion of patients achieving low-density lipoprotein cholesterol <2.5 mmol/L, glycated haemoglobin <48 mmol/mol, blood pressure <140/90 mm  Hg for patients without diabetes and <130/80 mm Hg for patients with diabetes and normoalbuminuria (urinary albumin creatinine ratio <30 mg/g) after 1 year of follow-up and the proportion of patients in each treatment group achieving low RA disease activity after 1 year, defined as a disease activity score C-reactive protein (DAS28-CRP) <3.2 and a DAS28-CRP score <2.6 after 12, 24 and 60 months. Furthermore, all hospitalisations for acute and elective reasons will be adjudicated by the event committee after 12, 24 and 60 months. Three hundred treatment-naive patients with early RA will be randomly assigned (1:1) to receive either conventional treatment administered and monitored by their general practitioner according to national guidelines (control group) or a stepwise implementation administered and monitored in a quarterly rheumatological nurse-administered set-up of behaviour modification and pharmacological therapy targeting (1) hyperlipidaemia, (2) hypertension, (3) hyperglycaemia and (4) microalbuminuria (intervention group). ETHICS AND DISSEMINATION: This protocol is approved by the local ethics committee (DK-S-2014007) and The Danish Health and Medicines Authority. Dissemination will occur through presentations at National and International conferences and publications in international peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT02246257.