Earlier quoted context omitted.
> When the DSMC met on Aug 5, 2021, it recommended that the TOGETHER trial stop randomly assigning patients to the fluvoxamine group, as this comparison had met the prespecified superiority criterion for the primary endpoint (prespecified superiority threshold 97·6%). This... is not how it's supposed to work.
Actually, it is. This is an adaptive clinical trial, meaning its part of the protocol to change when pre-set criteria are met. This is stated in the paper. There's a whole body of work on the ethics and statistics of adaptive clinical trials and when to stop them early if promising results are found. https://en.wikipedia.org/wiki/Adaptive_clinical_trial
> He also cautioned against “play the winner” designs that increase the number of patients being randomized to arms that show the best results in an interim analysis. “That is most often used in early phase trials, like a Phase I or early Phase II trial where you’re really trying to identify the best dose level; such trials tolerate bias pretty well,” Sietsema said. “But you wouldn’t use a play- the-winner model in a Phase III trial because the potential for bias could lead to a wrong decision and the FDA would object.”
That sums up my concerns pretty well. This is being presented as a phase III clinical trial demonstrating safety and efficacy. For the level of effect they are testing for, I don't see how an adaptive trial is appropriate here.