FDA clears trial of NanoKnife tech for enlarged prostate symptoms

AngioDynamics Inc. has received approval from the U.S. Food and Drug Administration to begin a feasibility study testing whether its NanoKnife System can relieve urinary symptoms caused by benign prostatic hyperplasia, the company announced.

The FDA approved the company's Investigational Device Exemption application to launch the study, called RELIEF, which will evaluate irreversible electroporation, a non-thermal tissue ablation method, as a potential treatment for lower urinary tract symptoms in men with the condition commonly known as an enlarged prostate.

Benign prostatic hyperplasia affects roughly 15 million men in the United States and leads to more than 300,000 surgical procedures each year, according to the company. The condition can cause urinary frequency, urgency, weak stream and incomplete bladder emptying that interfere with daily life.

Existing treatments range from medication to surgical options such as transurethral resection of the prostate, along with newer minimally invasive procedures. Company officials said the range of available approaches reflects an ongoing need for treatments that relieve symptoms while preserving sexual and urinary function.

"The NanoKnife System has an established role in the treatment of men with intermediate-risk prostate disease," said Juan Carlos Serna, AngioDynamics' senior vice president of scientific and clinical affairs, adding that physicians have reported improvements in urinary symptoms in patients following treatment with the device in earlier clinical use.

The NanoKnife System is already cleared for surgical ablation of prostate tissue. In earlier clinical use of the technology for treating intermediate-risk prostate disease, physicians observed related improvements in BPH-associated urinary symptoms, an observation that helped support the rationale for the new study.

RELIEF is designed as a prospective, single-arm study and will enroll 40 patients across as many as five clinical sites in the United States. Patients will be assessed at six months post-treatment for the study's primary endpoints and will continue to be followed for five years to evaluate secondary outcomes.

The primary effectiveness measure is the average change in International Prostate Symptom Score from baseline to six months after the procedure, while the primary safety measure is the rate and severity of device-related adverse events during that same window.

Felix Cheung, a urologic surgeon at Memorial Sloan Kettering Cancer Center, is serving as co-principal investigator for the study. Cheung said the trial was built around established measurement tools, including symptom scoring, uroflowmetry and quality-of-life assessments, along with tracking of sexual function and durability of results over the five-year follow-up period.

During the procedure, electrodes are inserted transperineally into targeted areas of the prostate using transrectal ultrasound guidance under general anesthesia. Treatment is planned to target prostate tissue on both sides of the gland while sparing surrounding structures, including the neurovascular bundles, external sphincter and urethra. The NanoKnife System works by delivering short electrical pulses that create permanent openings in cell membranes, producing precise tissue ablation without heat.

Broader momentum in minimally invasive urologic care

The push toward tissue-sparing treatment for enlarged prostate symptoms reflects a wider shift across urology toward technologies that aim to relieve symptoms while minimizing damage to surrounding anatomy. Over the past several years, a range of energy-based and mechanical approaches have moved from early trials into broader clinical use, driven largely by patient demand for options that reduce the risk of complications such as erectile dysfunction, retrograde ejaculation and incontinence that have historically accompanied more invasive surgical resection.

Water vapor therapy, which uses steam to destroy excess prostate tissue, has gained traction as an office-based option requiring minimal recovery time. Similarly, mechanical approaches that physically lift and hold enlarged prostate tissue away from the urethra have offered an alternative for men seeking to preserve ejaculatory function. Robotic-assisted waterjet ablation, which combines imaging with high-pressure water to remove tissue with precision, has also expanded into more clinical settings.

Across these technologies, researchers have increasingly emphasized long-term durability data and functional outcomes, not just short-term symptom relief, as regulators and physicians look for evidence that newer interventions can match the effectiveness of traditional surgery while reducing the side-effect burden. Experts say continued investment in five-year and longer follow-up studies, similar in structure to the design used in current device trials, suggests the field is moving toward establishing more definitive comparative evidence between minimally invasive techniques and conventional surgical standards of care.