I was thinking about this when the discussion about dosing amount. If the DSMC was asking for a 42 day readout and the dosing was limited to 2, what would they expect to see? The placebo patients may have fared worse and there could be more deaths and the Leronlimab group might have continued to recover? I would think the 2 doses happen in the first 2 weeks and then the patients are just observed for the protocol 28 days (2 weeks after 2nd dose), for the added 42 days the only difference would be longer observation.
My honest opinion is that because the DSMC did not change anything about the trial except the possible 75% enrollment and 42 day readout that the dosing was working. If it was not they would call the trial futile, or recommend changing the protocol, which they did not.