Hello!
I have a special study design and I need you advice. The study has a screening, then all subjects start to take drug A during the Run-in period. Then, before randomization, subjects are tested for a randomization criterion.
If they fail, the subjects do a special visit Run-in early termination (only for them) and are discontinued.
If they passed, they are randomized to A+B or A+C and they continue the study. The 2 study treatments to be compared are B and C.
My question is : Should we consider 2 or 3 Arms? I’ve seen examples when they would consider 2 arms and the subjects not randomized are assigned ARMCD=NOTASSGN. But as I need to create a special visit set for this arm because of the Run-in early termination visit, I am not clear it applies to my design.
Thank you for your help!