“They would only do so if there was a very good indication that 75% and 42 days would not only meet stat sig but would overcome the lower power of the lesser patient population.”

The DSMC likely wanted to see 42 day mortality for 292 patients (75%) in order to compare the results to 28 day mortality at 75%. The request to see 42 day data was separate from the sample size reassessment (power). Below is verbatim what the DSMC wrote in there not to CYDY at the 50% interim analysis, as read by NP on October 20th, 2020.

“The DSMC recommendation was to continue the trial as planned but to conduct another interim analysis when 75% of the planned subjects have been randomized and have been under study for 42 days, or withdrawn, which ever occurs first. Sample size reassessment will be considered at that interim analysis.”