How about just eliminating side effects. Even if it performs the same, but is safe and tolerable with no side effects, which would doctors and patients prefer?
Given the data available thus far it is highly unlikely that on average all AD patients treated with A2-73 will stabilise or even improve. Seems 2 patients did in the P2a extension at 148 weeks, whereas the rest declined some slow than the SOC posthoc comparison and a few faster.
Hard to know exactly how long a clinically meaningful improvement over SOC is sustained and for how many. I think there is good chance that overall A2-73 will beat SOC and with fewer side effects.