NeuroRx, Inc announced that it has initiated a pivotal Phase 2b/3 study for NRX-101 for the treatment of patients with Severe Bipolar Depression and Acute Suicidal Ideation and Behavior (ASIB).    NRX-101 has been granted Breakthrough Therapy Designation and Fast Track Designation by the U.S. FDA. The drug is designed to address bipolar depression with suicidal ideation, an indication for which there is no currently approved drug and for which the only FDA-approved treatment remains electrocon...