The EXPANDER-1 trial

Abstract

Purpose: To demonstrate the safety and feasibility of the Urocross Expander System (formerly branded as XFLO Expander System), an implantable nitinol tissue expander to trea t patients with lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH). Materials and methods: Men of 50 years or older were eligible to participate in the international, prospective, three-arm, open-label EXPANDER-1 trial if they had a prostate volume between 30 and 80 cc, prostatic urethra length between 20 and 60/80 mm, international prostate symptom score (IPSS) > 13, peak urinary flow (Qmax) < 12 mL/s, post-void residual (PVR) urine volume < 250 mL and quality of life (QoL) score ≥ 3. Patients had pre-assigned implant indwell times (1, 6, and 12 months for Arm-1, Arm-2 and Arm-3 respectively) with follow-up through 6 months (Arm-1) and 3 years (Arm-2 and Arm-3) post-retrieval. Results: Outcome from treated subjects with their 6-month post-retrieval will be presented in this manuscript, as data collection from longer-term follow-up is ongoing. As of May 24, 2021, 39 and 22 men (mean age: 65), respectively, had implants successfully deployed and retrieved without any complications. No cases of implant encrustation were observed. Device- and procedure-related adverse events were predominantly mild to moderate in severity. Three SAEs were reported. Only one patient required catheterization post-implant for more than three days. Improvements in clinical parameters such as IPSS, QoL, PVR and Qmax as well as sexual function were observed. Conclusions: Preliminary results demonstrate that the Urocross Expander System is a feasible and safe procedure for treating BPH/LUTS. A strong signal of efficacy justifies further evaluation of this PRostatic Urethral Expansion (PURE) procedure. Negative features of earlier generations of prostatic implants such as biocompatibility, migrations and encrustation have possibly been overcome.