Overview Open Label Extension Study of Nalbuphine HCl ER in Patients With Prurigo Nodularis Status: Completed Trial end date: 2017-09-03 Target enrollment: Participant gender: Summary The primary objective of the study is to evaluate the overall safety of nalbuphine HCL ER tablets during a treatment period of up to 50 weeks. Phase: Phase 2/Phase 3 Details Lead Sponsor: Trevi TherapeuticsTreatments: Nalbuphine