 So for instance, in cancer, they're able to look at the shrinkage of the tumor, and that's a predictor of whether the patient will live longer. And that allows them to bring a drug onto the market, oftentimes using only one clinical study, and much quicker than if they waited to measure survival. So is it FDA policies that you would say are mostly holding this up, or why do you think that there's such a stall on these particular medications?