A medicine that may bring people with bipolar depression and acute suicidal ideation a safer, non-hallucinogenic alternative to repeated ketamine use for relapse prevention has succeeded in a small midstage study, supporting pursuit of a pivotal trial by its developer, Neurorx Inc. The Philadelphia-based company said based on its phase II data, the FDA has granted the fixed-dose cycloserine/lurasidone combination, NRX-101, a breakthrough therapy designation and a special protocol assessment for the pivotal study, expected to begin in the second half of this year.