A Study to Evaluate the Long-Term Effect of TEV-48574 in Moderate to Severe Ulcerative Colitis or Crohn's Disease

The primary objective of the study is to evaluate the efficacy of 2 different maintenance dose regimens of TEV-48574 subcutaneous (sc) administered every 4 weeks (Q4W) in adult participants with inflammatory bowel disease (IBD). Secondary objectives of the study are to: * evaluate the efficacy of 2 different maintenance dose regimens of TEV-48574 sc administered Q4W in adult participants with IBD * evaluate the safety and tolerability of 2 different maintenance dose regimens of TEV-48574 sc administered Q4W in adult participants with IBD * evaluate the immunogenicity of 2 different maintenance dose regimens of TEV-48574 sc administered Q4W in adult participants with IBD The total duration for a participant in the double-blind period only is 66 weeks; and for a participant in the open-label extension (OLE) period, up to an additional 268 weeks.