ABSTRACT
An overview of ventricular arrhythmia drug trials is very instructive in terms of the types of trials a sponsor might perform and the types of results that might occur.
First, it is important to divide trials into those for acute problems and those for chronic conditions. They are very different. As Ray said, for chronic antiarrhythmic drug development, we should have a placebo as a comparator. In acute trials, when patients are in marked distress, it is very hard to use placebo, but I think that lidocaine, an active drug commonly used for acute arrhythmias, has little more than placebo effect. An article in the American Journal of Cardiology by Pacifico and colleagues from Baylor shows that, in acute ventricular tachycardia, lidocaine works in 8% of cases. Another population with ventricular tachycardia was studied in the Netherlands in Heinz Wellens laboratory to compare procainamide with lidocaine, and found procainamide to be considerably more effective than lidocaine. Nonetheless, at least in the U.S., lidocaine is still the first-line drug. It is given in emergencies before anything else. However, lidocaine has such a low efficacy and relatively high toxicity that it might be a good comparator in an acute drug trial.
