Extracorporeal Robotic HIFU for Symptomatic BPH: Initial Safety Results from a First-in-Human Study
Purpose: Benign prostatic hyperplasia (BPH) is a prevalent condition in aging men and a major cause of lower urinary tract symptoms (LUTS). Traditional endoscopic and surgical treatments, while effective, carry inherent risks of bleeding, urethral strictures, sexual dysfunction, and prolonged recovery due to the instrumentation utilized. High-intensity focused ultrasound (HIFU) enables targeted thermal ablation without tissue resection and has emerged as a potential non-invasive treatment modality for BPH.
The LOTUS-1 system (NINA Medical, Israel) is a novel investigational HIFU platform that combines real-time ultrasound-guided treatment planning, proprietary HIFU beam visualization imaging, robotic-assisted positioning, and a transperineal treatment approach designed to achieve precise transitional zone ablation while sparing sensitive surrounding structures.
We report initial procedural, safety, and early functional outcomes from the first three consecutively treated subjects, including one-month follow-up, in an ongoing prospective First-in-Human (FIH) study evaluating the safety and technical feasibility of LOTUS-1 in men with symptomatic BPH.
Materials and Methods: Three patients have been enrolled and treated in this ongoing prospective, single-arm FIH clinical investigation at the Rambam Health Care Campus, Haifa, Israel. Eligible subjects were men with moderate-to-severe lower urinary tract symptoms with baseline prostate volumes of 30 - 80 mL.
Treatment planning and HIFU delivery were performed under real-time transperineal ultrasound guidance. Periprocedural assessments included technical feasibility, procedure duration, sonication duration, and postoperative catheterization time.
Pre- and post- procedure contrast-enhanced dynamic MRI was used to assess ablations using Non-perfuse Volume (NPV) method.
Safety assessments included incidence, severity, and relationship of adverse events and serious adverse events to the device and/or procedure.
Results: The transperineal robotic HIFU procedure was successfully completed in all three subjects, with no intra-procedural technical failures, device malfunctions, or treatment discontinuations. Total procedure duration ranged from 45 to 120 minutes, with active HIFU sonication time of 2 minutes per subject.
Post procedural MRI demonstrated NPV within the targeted transitional zone.
No serious adverse events, unanticipated adverse device effects, significant bleeding, or evidence of off-target thermal injury were observed. All subjects were discharged within 24 hours without a urinary catheter and successfully passed their initial trial of voiding.
Two device-related adverse events were reported. One subject experienced Grade 1 dysuria and mild terminal haematuria beginning 2 days after treatment, resolving within 4 days with symptomatic treatment. A second subject experienced Grade 1 worsening urgency/nocturia and weak urinary stream beginning 2 days after treatment, with improvement following symptomatic therapy. No Grade ≥2 device-related adverse events have been reported to date.
Conclusions: Early results from this ongoing First-in-Human clinical investigation demonstrate the technical feasibility and favourable initial safety profile of the LOTUS-1 transperineal robotic HIFU system for the treatment of symptomatic BPH. All procedures were completed successfully without device-related serious adverse events, treatment discontinuations, or urinary catheter dependence beyond the first post-procedure day.
These preliminary findings support continued clinical evaluation approach. Further enrolment and longer-term follow-up are ongoing to characterize functional outcomes, durability of symptom relief, and the overall safety and performance profile of the LOTUS-1 system.