I'm not a medical professional but looking at the chart its...

I'm not a medical professional but looking at the chart its possible the high range of the chart is the natural maximum placebo effect which both xanamem and the placebo would be capped by assuming xanemem is useless. Now, one would expect xanemem and placebo to perform the same if xanemem were useless, but perhaps since the baseline of the placebo started so far below it had less resistance to reach the natural high and so outperformed xanemem. Unfortunately this would suggest xanemem is close to useless, however the xanemem benefits do remain beyond the placebo in the follow up, and so so in many other metrics, but the trial is not long enough to make any conclusions. Or, hopefully, the placebo results are a total anomaly