Clinical and technical evidence

A literature search was carried out for this briefing in accordance with the interim process and methods statement. This briefing includes the most relevant or best available published evidence relating to the clinical effectiveness of the technology. Further information about how the evidence for this briefing was selected is available on request by contacting mibs@nice.org.uk.

Published evidence

Four studies are summarised in this briefing: 1 blinded control trial, 1 single-arm pilot study, 2 retrospective observational studies, involving a total of 522 men with LUTS presumed secondary to BPH.

Table 2 summarises the clinical evidence as well as its strengths and limitations.

Overall assessment of the evidence

The evidence includes 1 blinded controlled trial involving multiple centres in the US (Rezum II trial). This trial intends to follow up patients for 5 years, and the most recent published findings at 3 years, McVary et al. (2018), are summarised in table 2. This study showed that, compared with a sham device or control procedure, Rezum showed significantly better symptom control 3 months after treatment and that the improvements over baseline are maintained at 3 years. One observational study (Dixon et al. [2015]) found no impairment of sexual function after Rezum treatment.

Table 2 Summary of selected studies

McVary et al. (2018)

Study size, design and location

197 men aged 50 and over with IPSS≥13, a prostate volume of 30cc to 80cc, Qmax≤15 ml/s, and a measured PVR urine<250 ml; prospective multicentre blinded control trial, US.

Intervention and comparator(s)

Intervention: Rezum.

Control: Sham or control procedure with rigid cystoscopy.

Key outcomes

Primary outcome: IPSS reduction at 3 months, −11.3 +/−7.6 Rezum compared to −4.3 +/−6.9 control, p<0.0001. Statistically significant (p<0.0001) improvements in IPSS compared to control were further seen at 6, 12, 24 and 36 months' follow-up compared to baseline.

There was a statistically significant improvement (p<0.0001) in QoL scores (IPSS QoL, BPHII, ICS IS, and OAB HQoL), as well as Qmax, at 3 months for Rezum compared to the control group, and at 6, 12, 24 and 36 months compared to baseline.

No significant difference was seen in measures of ejaculatory function and erectile function between Rezum, with the exception of ejaculatory function at 36 months, p=0.0033.

Strengths and limitations

The study reports a large number of outcomes to 3 years' follow-up from a trial that intends to follow patients for up for 5 years. However it is powered for the primary outcome at 3 months. Control patients were unblinded at 3 months, and if they elected to continue were crossed over into the intervention arm. The study is funded by the company, and one of the authors declared a financial interest in the company.

Dixon et al. (2015)

Study size, design and location

65 men aged 45 and over with IPSS ≥15, a prostate volume of 20 ml to 120 ml, Qmax ≤15 ml/s, and a measured PVR urine<300 ml; multicentre (Dominican Republic, Czech Republic, and Sweden) single-arm pilot studies.

Intervention and comparator(s)

Intervention: Rezum.

No control.

Key outcomes

Statistically significant (p<0.001) clinical improvements over baseline at 1, 3, 6, and 12 months were reported for IPSS (decreased by 6.8, 13.4, 13.1, and 12.5 points respectively) and Qmax (increased by 2.0, 4.7, 4.3, and 4.6 ml/sec respectively) equating to a 56% improvement in IPSS and an 87% improvement in Qmax. QoL also improved (p<0.001) at collection points over 12 months. There were no significant changes in sexual function measures, meaning sexual function was maintained. 125 adverse events were recorded in 45 patients, most of which were minor (Clavien Dindo grade 1), of short duration and related to endoscopic instrumentation.

Strengths and limitations

Treatment approach and dosimetry varied from the first patients at the first site (Dominican Republic) to the final patients in Sweden. This and the lack of a control make the results harder to interpret. The study was sponsored by the company, and all but 1 of the authors were paid consultants or study investigators funded by the company.

Darson et al. (2017)

Study size, design and location

131 patients, multicentre, retrospective observational study of consecutive patients with moderate to severe (IPSS 8 to 35) LUTS at 2 large medical practices in US.

Intervention and comparator(s)

Intervention: Rezum.

No comparator.

Key outcomes

There were significant improvements (reductions) in IPSS scores (p<0.0001) from baseline values at 1, 3, 6 and 12 months, in QoL (IPSS question 8) scores, and PVR volumes. These results were found for all patients and when split into moderate (IPSS 8 to 19) and severe (IPSS 20 to 35) subgroups. The differences from baseline for Qmax and voided volume were not statistically significant (p>0.05), except for Qmax 3 to 6 months, all patients and moderate LUTS.

Strengths and limitations

The study confirms the findings from randomised studies, but is limited by the lack of a control. Three of the authors, including the lead author, have acted as consultants for the company.

Mollengarden et al. (2017)

Study size, design and location

129 patients, retrospective observational study involving a single surgeon and practice in Texas, US.

Intervention and comparator(s)

Intervention: Rezum.

No comparator.

Key outcomes

There were statistically significant improvements (p<0.001) in IPSS and Qmax at 15 to 45 days, 46 to 90 days, and 91 to 180 days post-operation; and in PVR (p<0.05) over the same periods. These results were largely consistent across the sub groups evaluated: whether or not a median lobe was treated, whether the prostate was greater or less than 60 cc, whether preoperative PVR was greater or <200 ml, and whether preoperative LUTS were mild, moderate, or severe.

The most common adverse even was urinary tract infection (17.1%), followed by urinary retention (14%).

Strengths and limitations

The study includes 25 patients who were also involved in the Rezum II trial, see McVary et al. (2015). The lack of a standardised follow-up, and the retrospective analysis design meant that there was a noticeable loss to follow-up and variation in collection rates for different outcomes.

Abbreviations: BPHII, Benign Prostatic Hyperplasia Impact Index; HQoL, health-related quality of life; ICS IS, International Incontinence Society Incontinence Scale; IPSS, International Prostate Symptom Score; LUTS, lower urinary tract symptoms; OAB, overactive bladder; PVR, post-void residual; Qmax, peak urinary flow; QoL, quality of life.

Recent and ongoing studies

  • Rezum FIM Optimization. Clinical trials identifier: NCT02940392. Status: Active, not recruiting, no results posted. Indication: individuals with BPH symptoms, 15 enrolled. Devices: Rezum system, estimated completion date: June 2018.

  • Rezum I Pilot Study for BPH. Clinical trials identifier: NCT02943070. Status: Active, not recruiting, no results posted. Indication: individuals with BPH symptoms, 50 enrolled. Devices: Rezum system, estimated completion date: December 2018.