Most statistical frameworks treat errors symmetrically. A false positive is bad. A false negative is bad. Control one, tolerate the other, and let the math do the rest. Clinical reality is not that tidy. Approving an ineffective therapy and withholding a potentially effective one are both errors, but they do
In September 2016, the FDA approved eteplirsen for Duchenne muscular dystrophy. The advisory committee had voted 7 to 6 against accelerated approval. The FDA's own review team recommended against it. The clinical program consisted of 12 boys, and western blot analysis showed a dystrophin increase of 0.93%
Between late 2024 and late 2025, FDA approved six rare-disease therapies supported primarily by single-arm trials. None of these sponsors ran randomized controlled trials. All received traditional or accelerated approval. What separated success from rejection wasn’t luck or regulatory leniency. It was understanding what evidence compensates for the absence
