Intravenous treprostinil infusion via a fully implantable pump for pulmonary arterial hypertension

Objectives Parenteral prostanoids infused via external pumps are well-established pulmonary arterial hypertension (PAH) treatments. However, local side-effects and systemic infections restrict their use. The purpose of this study was to investigate the safety of a fully implantable treprostinil infusion pump (LENUS Pro (R)) in patients with PAH. Methods Thirty patients with PAH undergoing pump implantation (with stable PAH therapy for >= 3 weeks preimplantation) were included in this prospective, multicenter, observational study (NCT01979822). Primary endpoints were predefined adverse events (AEs) during implantation, in-hospital and/ or during 6-month follow-up. Refill-related AEs were a secondary endpoint. Results Twenty-nine patients completed 6-month followup (one underwent lung transplantation). During implantation, one pneumothorax (not requiring drainage) occurred. Four patients had an in-hospital AE (including one catheter revision). During 6-month follow-up, AEs were most frequent at the first refill (10); the most common AE was seroma around the pump. No infections occurred. One pump required replacement because of a defective septum caused by use of a non-approved refill needle (associated with extravasation). Apart from the extravasation, no refillrelated AEs were recorded. Post hoc efficacy analyses showed significant improvements in functional class [ number in functional class I/II/III/IV: 0/5/21/2 (baseline) versus 3/8/17/0 (6 months); p = 0.012] and 6-min walk distance (mean +/- standard deviation: 407 +/- 122 m versus 445 +/- 127 m; n = 17; p = 0.014). Conclusions This study supports use of a fully implantable treprostinil infusion pump in patients with PAH requiring parenteral prostanoids. Refills should be performed by specialized healthcare professionals at patients' homes or at experienced centers using approved equipment.