Another trial stopped early because of benefit is EMPHASIS-HF (Eplerenone in Mild Patients Hospitalisation And SurvIval Study in Heart Failure) which looked at the aldosterone inhibitor, eplerenone, in mild heart-failure patients.
According to Pfizer, an interim analysis of the trial showed that patients treated with eplerenone in addition to current standard of care experienced a significant reduction in risk of cardiovascular death or heart failure hospitalisation compared with those in the placebo arm of the trial.
The company says it is now working to ensure that all patients are informed of this decision, and an amendment to the protocol will be requested to allow all consenting patients to start treatment with eplerenone in an open-label extension of the study, after completing a close-out visit ending the double-blind, placebo-controlled phase.
Eplerenone is currently approved for hypertension and for use in addition to optimal medical therapy early after acute myocardial infarction in patients with congestive heart failure.
The routine use of oxygen in the treatment of myocardial infarction (MI) patients is questioned in a new analysis in the Cochrane Database of Systematic Reviews.
The authors, led by Dr Juan Cabello (Hospital General Universitario de Alicante, Spain) and Professor Tom Quinn (University of Surrey, Guildford) say there is no conclusive evidence from randomised controlled trials to support the routine use of inhaled oxygen in patients with acute MI, and the available clinical trial data suggest that oxygen might actually be harmful.
A definitive randomised controlled trial is urgently required given the mismatch between trial evidence suggestive of possible harm from routine oxygen use and recommendations for its use in clinical practice guidelines, they add.
For the review, published on June 16, 2010, the authors pooled the results of three randomised trials involving 387 MI patients. Results showed that oxygen use was associated with a relative risk of death of 2.88 in an intention-to-treat analysis and 3.03 in patients with confirmed MI. While suggestive of harm, the small number of deaths (14) meant that this could be a chance occurrence, they point out.
They note that as long ago as 1950, it was demonstrated that the administration of pure oxygen not only failed to reduce the duration of angina pain but also prolonged the electrocardiographic changes indicative of an MI, adding that: “It is surprising that a definitive study to rule out the possibility that oxygen may do more harm than good has not been done”.