This isn't anything new, but its implications are more disturbing that i realized at first
"Meta-analyses of antidepressant medications have reported only modest benefits over placebo treatment, and when unpublished trial data are included, the benefit falls below accepted criteria for clinical significance."
We've already accepted that antidepressants usually aren't very effective except in the cases of severe depression, and even then it's minimal. But any meta analysis for a medication is only going to be based off the clinical trials that were published.
The only sorts of clinical trials that get published are ones that show some sort of modest benefit. Because if it ends up that the study was a failure, nobody wants to promote the inefficacy of a product, the researchers won't get paid.
For antipsychotic medications, typically about 80% of the people discontinue treatment before the trial is over. Then they use the 20% that didn't get poisoned from it and see if the effect size reaches mild significance.
TL;DR: If you want to get your medication approved, make sure it seems like it may be mildly beneficial (even with all the side effects) by literally just disregarding any data that shows it to be ineffective or even harmful. Make billions.