The goal of this clinical trial is to learn if ACP-211 can help treat adults with major depressive disorder (MDD) who have not improved with antidepressant therapy (ADT), including those with treatment resistant depression (TRD). The main questions the study aims to answer are: * Does ACP-211 work better than a placebo (a look-alike capsule with no medicine) to reduce symptoms of depression? * What adverse events do participants have when taking ACP-211?
Phase 2 trials begin testing efficacy in a larger patient group (100–300). This is often where biotech binary events occur — positive Phase 2 data can significantly advance a company's pipeline narrative, while failures can be terminal for a program.
Currently recruiting: the trial is enrolling patients. A data readout is not expected until after enrollment closes and the follow-up period is complete.
ACADIA Pharmaceuticals (ACAD) is the sponsoring company for this trial. BiotechSign currently grades this company B (77/100) based on composite catalyst signals across its full pipeline. This trial is one data point in that overall catalyst picture.