Open-Label Extension Study of Ubenimex in Patients With Pulmonary Arterial Hypertension (WHO Group 1)

This study is a Phase 2, open-label, multicenter, extension study to evaluate long-term safety and efficacy of ubenimex in patients with PAH (WHO Group 1) who complete Study EIG-UBX-001 (Study EIG-UBX-001 is a Phase 2, randomized, double-blind, placebo-controlled clinical trial) and meet the eligibility criteria for Study EIG-UBX-002. The primary objective for this study is: \- to obtain long-term safety and tolerability data for ubenimex (150 mg administered three times daily \[TID\]) in patients with PAH (WHO Group 1).