The National Prescribing Centre has published MeReC Extra 43 (PDF) which contains an update on the current evidence regarding the clinical significance of the interaction between clopidogrel and proton pump inhibitors (PPIs) and details from two new studies in chronic obstructive pulmonary disease (COPD).
The antithrombotic effect of clopidogrel has been shown to be attenuated by PPIs at a pharmacokinetic level however the clinical significance of this interaction remains in debate. This MeReC reports results from a large observation study and an analysis of two randomised controlled trials (RCTs). These studies did not find a statistically significant increase in the rate of cardiovascular events in patients taking the combination. Clinicians are advised to continue to follow the current recommendations while this interaction is researched further.
This MeReC also discusses recent research in COPD. A systematic review of the risks and benefits of combination treatment with an inhaled corticosteroid (ICS) and long-acting beta-agonist (LABA) compared with a long-acting beta-agonist alone. The review found that there was no reduction of severe exacerbations, all-cause, respiratory or cardiovascular mortality associated with the combination treatment when compared to LABA alone. Combination therapy was associated with some adverse events including fungal, viral and bacterial infections of the respiratory tract, for example pneumonia.
Finally, a short term RCT compared the addition of a combination ICS/LABA (budesonide/formeterol) to tiotropium alone. The study design has several limitations and therefore the results need careful interpretation, clinicians are advised that practice should not change based upon this study alone.
Action: Clinicians who see patients with vascular disease or COPD will find this information useful and informative.