Kar-XT adds trospium to xanomeline to substantially improve the second agent’s tolerability, enabling its use to reduce both positive and negative symptoms in schizophrenia. Allopregnanolone, an oral version of brexanolone, is being investigated in MDD. The dextromethorphan and bupropion combo, AXS-05, seeks to offer a new antidepressant option and hydroxynorketamine promises MDD treatment without ketamine’s dissociative effects and abuse potential.