NorthWest Biotherapeutics Inc (NWBO)

[exwannabe]

It was a partial screening halt at the time. Years, literally years later, we learned (via the 2.3 to 1 published ratio) they almost certainly stopped enrolling anymore placebos once the partial screening halt was placed into effect. A suspicion many longs had prior to learning the final treatment arms ratio.

It was a halt on new patient screening. As MI_DNDN correctly noted, it would be unethical to have patients sign a consent form if there had been a futility rec, so the FDA called it an ethical issue to do so. NWBO tried for over a year to get the FDA to change their minds, but failed. Eventually NWBO changed the trial to call it over. As this change to the IND no longer had an ethical issue with patients signing the consent, the FDA lifted the hold.

As far as the imbalance, that is an unknown. NWBO is on public record saying no other change to trial happened other than shutting down new patient screening. And for the FDA to screw with the trial design in such a way would be insane. Far better for the trial to just shut down the pipeline and toss the patients into the CA arm. That would not have created the bias that a non-randomized late cohort would.