Yeah the FDA is also being pretty lenient about allowing single-arm trials for gene therapy for this reason. The effect size needs to be obvious, but there's n

Yeah the FDA is also being pretty lenient about allowing single-arm trials for gene therapy for this reason. The effect size needs to be obvious, but there's no reason to subject 3/6 deaf children to being a control if the risk is relatively low and the odds of success are high. (also, for many of theses diseases, there's no plan B -- if it's not fixed in early childhood, you can never interpret sound).