 Shares of Provention Bio Inc. PRVB, -1.09 were down 3.9 in trading on Friday morning, the day after the Food and Drug Administration approved the companys treatment that can delay the onset of Type 1 diabetes in some patients. The intravenous therapy, Tzield, can delay the onset of Stage 3 Type 1 diabetes in patients with Stage 2 Type 1 diabetes. 