Clinical Data
Two clinical investigations of the ZIDA Wearable Neuromodulation System were conducted in the United States at a single center to obtain clinical information to demonstrate whether the device is substantially equivalent to the predicate device, the Urgent PC Neuromodulation System. The initial investigation enrolled 23 out of a planned 50 patient study but was stopped to amend the clinical protocol to obtain effectiveness information. After the protocol was amended, the second trial was launched enrolling 40 subjects. In total, 63 subjects, were randomized 1:1 to treatment with the device or sham-treatment with the device not activated.
The primary objective of the first study was to assess the Quality of Life (QoL) of subjects treated with the ZIDA device. The second study sought to determine whether the ZIDA device was substantially equivalent in terms of safety and effectiveness to the Urgent PC device in treating overactive bladder (OAB) symptoms of urinary urgency, urinary frequency, and urge incontinence. Subjects were diagnosed with OAB based on meeting the criteria defined by the International Continence Society, i.e., subjects with an average urinary frequency: ≥8 voids and ≥1 urgency episode (with or without incontinence) per 24 hours and who had a normal urinalysis and a score of 60 or higher on the Incontinence impact questionnaire-OAB-q Short Form, 4-week recall were considered eligible for the study. Subjects were provided the device and instructed to have once-weekly treatments of 30 minutes with the device for 12 consecutive weeks. The ZIDA device was self-administered by the subject at home. Participants reported 100% compliance with all weekly treatments for 12 weeks on both arms in both studies. In the second study, treatment success was defined as at least a 50% reduction in urinary urgency voids with or without incontinence or at least a 30% reduction in the frequency of daytime or nighttime voids from baseline to week 12. The treatment success rate in the ZIDA device arm was 80%, as compared to the treatment success rate of 39% in the sham control arm. Hence, the primary endpoint of the study was considered met. Subjects on the ZIDA device had a greater decrease in the number of urgent episodes from baseline to Week 12 as compared to subjects on sham control; a greater decrease in the number of incontinence episodes from baseline to Week 12 compared to sham control, and a greater decrease in the total number of voids per day from baseline to Week 12 compared to sham control. The study results from the second study based on the bladder diaries (urinary frequency, urinary urgency, and urinary incontinence) for the ZIDA device were similar to the results based on the bladder diaries reported in the studies evaluating the predicate Urgent PC device.
Two adverse events (AEs) were reported over the course of the first study, both in the sham control arm and both considered unrelated to the device. Five AEs were reported over the course of the second study: two subjects, both in the active ZIDA device arm, reported a mild AE of urinary tract infection which was not considered related to the study treatment; and two subjects, also both in the active ZIDA device arm, reported an expected mild AE of pain in the foot during or immediately after treatment that resolved within half an hour of treatment cessation.
In both the first and second studies, quality of life was improved in subjects treated with the ZIDA device compared to those in the sham control arms. In the second study, subjects in the ZIDA device arm reported greater satisfaction with the ZIDA device and improvement of OAB symptoms than subjects in the sham control arm. Subjects in the ZIDA device group were more likely to recommend the device compared to those in the sham control group.
In summary, the clinical information obtained in the 2 studies indicates that the ZIDA device is substantially equivalent, in improving symptoms of urinary incontinence, urinary urgency, and total urinary frequency well as improving quality of life for subjects with overactive bladder, to the predicate device Urgent PC Neuromodulation System.
Safety
Seven adverse events (AEs) were reported over the course of the two studies during the follow up visit calls, 3 in the sham arm and 4 in the ZIDA device arm. One subject in the sham control arm reported suspected COVID-19 symptoms and general poor health and dropped out of the study at the end of Week 4. Three subjects, two in the ZIDA device arm and one in the sham arm, reported a mild AE of urinary tract infection which was not considered related to the study treatment. One subject in the sham control arm reported a trauma related infection: leg sore on right leg on center of shin bone that was not considered related to treatment. Two subjects, both in the ZIDA device arm, reported a mild AE of pain in the foot during or after treatment that resolved after half an hour on Week 1 or Week 4 of treatment. These AEs were considered related to treatment. Subjects reported 100% compliance with all weekly treatments on both treatment arms while on study in both studies.
Effectiveness
In the second study, treatment success was defined as at least a 50% reduction in urinary urgency voids with or without incontinence or at least a 30% reduction in the frequency of daytime or nighttime voids from baseline to week 12. The treatment success rate in the ZIDA device arm was 80%, significantly larger than the treatment success rate of 39% in the sham control arm (p=0.02). Hence, the primary endpoint of the study was met. As presented in the table, subjects on the ZIDA device had a significantly larger decrease in number of urgent episodes from baseline to Week 12 compared to subject on sham control (p=0.03), a significantly larger decrease in the number of incontinence episodes from baseline to Week 12 compared to sham control (p=0.004), and a larger decrease in the total number of voids per day from baseline to Week 12 compared to sham control (p=0.06). In the first study, the subjects did not complete a bladder diary and therefore this information was not available.
In both the first and second studies, quality of life was significantly improved from baseline to Week 12 in subjects on the ZIDA device compared to those on the sham control as measured by the OAB-q SF. Hence, the key secondary endpoint in the second study and the primary endpoint of the first study were met.
When combining the subjects from both studies, change in quality of life from baseline to Week 12 was similar in each treatment arm for Caucasian subjects and Hispanic subjects. Quality of life was significantly improved in both Caucasian subjects and Hispanic subjects from baseline to Week 12 in subjects on the ZIDA device compared to those on the sham control as measured by the OAB-q SF. Therefore, the results in this study can be generalized to both Caucasian and Hispanic individuals.
In summary, the ZIDA device is safe and effective in reducing urinary incontinence, urinary urgency, and total urinary frequency of daytime and nighttime voids as well as improving quality of life for subjects with overactive bladder. The ZIDA device was self-administered by the subject at home and was reported to be easy to use with 100% treatment compliance for 12 weeks.
Table. Baseline and Week 12 Bladder Diary and Quality of Life Results by Treatment Arm
| ZIDA Device (N=21*) | Sham Control (N=19*) | |
|---|---|---|
| Variable | Mean (Std) Median (Min, Max) | Mean (Std) Median (Min, Max) |
Total Daily VoidsBaselineWeek 12 Change from Baseline to W12% Reduction Baseline to W12 | 11.7 (3.6) 9.9 (4.4) -2.0 (1.7) 18% (0.1) 10.2 (8.2, 21.3) 8.3 (5.7, 22.7) -2.1 (-5.7, 1.3) 19% (-7%, 40%) | 11.7 (3.6) 9.9 (4.4) -2.0 (1.7) 18% (0.1) 10.2 (8.2, 21.3) 8.3 (5.7, 22.7) -2.1 (-5.7, 1.3) 19% (-7%, 40%) |
Urgent Daily VoidsBaselineWeek 12 Change from Baseline to W12% Reduction Baseline to W12 | 5.2 (3.7) 2.1 (2.3) -3.3 (2.7) 62% (0.3) 3.8 (1, 14.2) 1.1 (0, 7.8) -2.8 (-9.7, 1.2) 71% (-18%, 100%) | 4.7 (2.9) 3.6 (3.2) -1.3 (3.4) 13% (0.8) 4 (1, 10.2) 2.8 (0.5, 11.7) -1.1 (-6.3, 6.8)40% (-175%, 83%) |
Urgent Daily VoidsBaselineWeek 12 Change from Baseline to W12% Reduction Baseline to W12 | 1.2 (0.8) 0.3 (0.3)-1.0 (0.7) 71% (0.3) 7 (35%) 1.3 (0, 3) 0.2 (0, 1) -1.2 (-2.2, 0) 79% (0%, 100%) | 1 (0.7)0.6 (0.7) -0.4 (0.6) 40% (0.4) 4 (22%) 1 (0, 2.3)0.3 (0, 2.2) -0.2 (-1.8, 0.3) 33% (-20%, 100%) |
Treatment Success (Urgency)Treatment Success (Incontinence)Treatment Success (Total Voids) | 16 (80%) 15 (75%) 5 (25%) | 7 (39%)6 (33%) 0 (0%) |
Quality of Life OAB-q SFBaseline Week 6 Week 12 Reduction** from Baseline to W12 | 74.3 (10) 53.1 (12.7) 45.6 (13.1) 29.1 (16.5) 73 (61, 102) 52 (29, 76) 46.5 (21, 68) 26 (2, 77) | 77.4 (11.1) 66.5 (11) 59.8 (14.4) 17.7 (12.8) 73 (63, 102)65 (47, 88) 58 (33, 84) 19 (-8, 35) |
*At Week 12 one sham control subject and one ZIDA device subject did not have bladder diary data. These subjects are excluded from Week 12 data. At Week 6 and 12 one sham subject did not have QOL data and at Week 12, one ZIDA device subject did not have QOL data.
**Change from baseline to Week 12 was calculated for each subject. Negative scores indicated a reduction in total QOL scores. Lower total QOL scores indicates improvement in QOL. The table presents the average reduction in QOL scores from baseline to Week 12.