Trial Outcomes & Findings for ROBUST III- Re-Establishing Flow Via Drug Coated Balloon For The Treatment Of Urethral Stricture Disease (NCT NCT03499964)

Last Updated: 2025-10-15

Results Overview

The percentage of subjects deemed to be stricture free will be compared between arms. Stricture free subjects are those for which a 16F flexible cystoscope or 14F Foley catheter is able to be passed through the treated stricture without significant resistance.

Recruitment status

ACTIVE_NOT_RECRUITING

Study phase

Target enrollment

127 participants

Primary outcome timeframe

6 months

Results posted on

2025-10-15

Participant Flow

Participant milestones

Participant milestones
Measure	Optilume Treatment The treatment arm will be the Urotronic Optilume Drug Coated Balloon (DCB). Optilume Drug Coated Balloon (DCB): The Optilume Drug Coated Balloon (DCB) is a guidewire compatible catheter with a tapered atraumatic tip. The distal end of the catheter has an inflatable balloon coated with a proprietary coating containing the drug paclitaxel that facilitates the drug's transfer to the urethral wall upon inflation.	Control Treatment The control arm will be treated by a urethral dilation method considered to be best standard of care for the study site and subject. A control treatment may be either a rod, uncoated balloon or DVIU. Control Treatment: A control subject may be dilated with either a rod, uncoated balloon or DVIU until the desired result is reached, based on standard of care for the clinical site and treating physician
Overall Study STARTED	79	48
Overall Study COMPLETED	68	21
Overall Study NOT COMPLETED	11	27

Reasons for withdrawal

Reasons for withdrawal
Measure	Optilume Treatment The treatment arm will be the Urotronic Optilume Drug Coated Balloon (DCB). Optilume Drug Coated Balloon (DCB): The Optilume Drug Coated Balloon (DCB) is a guidewire compatible catheter with a tapered atraumatic tip. The distal end of the catheter has an inflatable balloon coated with a proprietary coating containing the drug paclitaxel that facilitates the drug's transfer to the urethral wall upon inflation.	Control Treatment The control arm will be treated by a urethral dilation method considered to be best standard of care for the study site and subject. A control treatment may be either a rod, uncoated balloon or DVIU. Control Treatment: A control subject may be dilated with either a rod, uncoated balloon or DVIU until the desired result is reached, based on standard of care for the clinical site and treating physician
Overall Study Lack of Efficacy	6	26
Overall Study Adverse Event	1	0
Overall Study Death	1	0
Overall Study Withdrawal by Subject	2	1
Overall Study Lost to Follow-up	1	0

Baseline Characteristics

ROBUST III- Re-Establishing Flow Via Drug Coated Balloon For The Treatment Of Urethral Stricture Disease

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Optilume Treatment n=79 Participants The treatment arm will be the Urotronic Optilume Drug Coated Balloon (DCB). Optilume Drug Coated Balloon (DCB): The Optilume Drug Coated Balloon (DCB) is a guidewire compatible catheter with a tapered atraumatic tip. The distal end of the catheter has an inflatable balloon coated with a proprietary coating containing the drug paclitaxel that facilitates the drug's transfer to the urethral wall upon inflation.	Control Treatment n=48 Participants The control arm will be treated by a urethral dilation method considered to be best standard of care for the study site and subject. A control treatment may be either a rod, uncoated balloon or DVIU. Control Treatment: A control subject may be dilated with either a rod, uncoated balloon or DVIU until the desired result is reached, based on standard of care for the clinical site and treating physician	Total n=127 Participants Total of all reporting groups
Age, Continuous	58.7 Years STANDARD_DEVIATION 15.5 • n=5 Participants	60.6 Years STANDARD_DEVIATION 16.0 • n=7 Participants	59.4 Years STANDARD_DEVIATION 15.7 • n=5 Participants
Sex: Female, Male Female	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Sex: Female, Male Male	79 Participants n=5 Participants	48 Participants n=7 Participants	127 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	3 Participants n=5 Participants	3 Participants n=7 Participants	6 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	75 Participants n=5 Participants	45 Participants n=7 Participants	120 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	1 Participants n=5 Participants	0 Participants n=7 Participants	1 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants
Race (NIH/OMB) Asian	3 Participants n=5 Participants	2 Participants n=7 Participants	5 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	1 Participants n=5 Participants	0 Participants n=7 Participants	1 Participants n=5 Participants
Race (NIH/OMB) Black or African American	9 Participants n=5 Participants	6 Participants n=7 Participants	15 Participants n=5 Participants
Race (NIH/OMB) White	65 Participants n=5 Participants	39 Participants n=7 Participants	104 Participants n=5 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	1 Participants n=5 Participants	0 Participants n=7 Participants	1 Participants n=5 Participants
Region of Enrollment Canada	4 participants n=5 Participants	2 participants n=7 Participants	6 participants n=5 Participants
Region of Enrollment United States	75 participants n=5 Participants	46 participants n=7 Participants	121 participants n=5 Participants
Stricture Etiology Iatrogenic	21 Participants n=5 Participants	16 Participants n=7 Participants	37 Participants n=5 Participants
Stricture Etiology Idiopathic	42 Participants n=5 Participants	22 Participants n=7 Participants	64 Participants n=5 Participants
Stricture Etiology Inflammatory	1 Participants n=5 Participants	2 Participants n=7 Participants	3 Participants n=5 Participants
Stricture Etiology Traumatic	14 Participants n=5 Participants	7 Participants n=7 Participants	21 Participants n=5 Participants
Stricture Etiology Unknown	1 Participants n=5 Participants	1 Participants n=7 Participants	2 Participants n=5 Participants
Anatomic Stricture Location Bulbar Urethra	71 Participants n=5 Participants	45 Participants n=7 Participants	116 Participants n=5 Participants
Anatomic Stricture Location Penile Urethra	8 Participants n=5 Participants	2 Participants n=7 Participants	10 Participants n=5 Participants
Anatomic Stricture Location Unknown	0 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants
Stricture Length	1.63 cm STANDARD_DEVIATION 0.76 • n=5 Participants	1.72 cm STANDARD_DEVIATION 0.73 • n=7 Participants	1.67 cm STANDARD_DEVIATION 0.75 • n=5 Participants
Prior Dilations	3.0 Dilations STANDARD_DEVIATION 1.73 • n=5 Participants	3.0 Dilations STANDARD_DEVIATION 7.7 • n=7 Participants	3.0 Dilations STANDARD_DEVIATION 4.78 • n=5 Participants

PRIMARY outcome

Timeframe: 6 months

Population: Only subjects with cystoscopy completed at 6 month visit or with known repeat intervention were included in this analysis

Outcome measures

Outcome measures
Measure	Optilume Treatment n=67 Participants The treatment arm will be the Urotronic Optilume Drug Coated Balloon (DCB). Optilume Drug Coated Balloon (DCB): The Optilume Drug Coated Balloon (DCB) is a guidewire compatible catheter with a tapered atraumatic tip. The distal end of the catheter has an inflatable balloon coated with a proprietary coating containing the drug paclitaxel that facilitates the drug's transfer to the urethral wall upon inflation.	Control Treatment n=41 Participants The control arm will be treated by a urethral dilation method considered to be best standard of care for the study site and subject. A control treatment may be either a rod, uncoated balloon or DVIU. Control Treatment: A control subject may be dilated with either a rod, uncoated balloon or DVIU until the desired result is reached, based on standard of care for the clinical site and treating physician
Percentage of Subjects Stricture Free	50 Participants	11 Participants

PRIMARY outcome

Timeframe: 3 months

Rate of Major Device or Procedure Related complications

Outcome measures

Outcome measures
Measure	Optilume Treatment n=79 Participants The treatment arm will be the Urotronic Optilume Drug Coated Balloon (DCB). Optilume Drug Coated Balloon (DCB): The Optilume Drug Coated Balloon (DCB) is a guidewire compatible catheter with a tapered atraumatic tip. The distal end of the catheter has an inflatable balloon coated with a proprietary coating containing the drug paclitaxel that facilitates the drug's transfer to the urethral wall upon inflation.	Control Treatment n=48 Participants The control arm will be treated by a urethral dilation method considered to be best standard of care for the study site and subject. A control treatment may be either a rod, uncoated balloon or DVIU. Control Treatment: A control subject may be dilated with either a rod, uncoated balloon or DVIU until the desired result is reached, based on standard of care for the clinical site and treating physician
Safety: Rate of Major Device or Procedure Related Complications	0 Participants	0 Participants

SECONDARY outcome

Timeframe: 6 months

Population: Patients with a measured Qmax at baseline and 6 months. Subjects that underwent repeat treatment for a recurrent stricture had the last observed Qmax value prior to repeat treatment utilized (worst case imputation).

Change in peak urinary flow rate (Qmax) from baseline to 6 months post treatment. Positive values indicate an increase in Qmax from baseline to 6 months, while negative values indicate a decrease in Qmax.

Outcome measures

Outcome measures
Measure	Optilume Treatment n=67 Participants The treatment arm will be the Urotronic Optilume Drug Coated Balloon (DCB). Optilume Drug Coated Balloon (DCB): The Optilume Drug Coated Balloon (DCB) is a guidewire compatible catheter with a tapered atraumatic tip. The distal end of the catheter has an inflatable balloon coated with a proprietary coating containing the drug paclitaxel that facilitates the drug's transfer to the urethral wall upon inflation.	Control Treatment n=44 Participants The control arm will be treated by a urethral dilation method considered to be best standard of care for the study site and subject. A control treatment may be either a rod, uncoated balloon or DVIU. Control Treatment: A control subject may be dilated with either a rod, uncoated balloon or DVIU until the desired result is reached, based on standard of care for the clinical site and treating physician
Change in Qmax (Peak Flow Rate)	8.8 mL/Sec Standard Deviation 9.2	4.1 mL/Sec Standard Deviation 7.2

SECONDARY outcome

Timeframe: 12 months

The proportion of subjects considered to be therapeutic responders, defined as an improvement of greater than or equal to 50% in the International Prostate Symptom Score \[IPSS\] without repeat intervention, in the Optilume DCB arm at 12 months will be compared to a performance goal of 50%. The IPSS was developed to measure symptom severity for bladder outlet obstruction, with a range of 0 (no symptoms) to 35 (worst possible symptoms).

Outcome measures

Outcome measures
Measure	Optilume Treatment n=59 Participants The treatment arm will be the Urotronic Optilume Drug Coated Balloon (DCB). Optilume Drug Coated Balloon (DCB): The Optilume Drug Coated Balloon (DCB) is a guidewire compatible catheter with a tapered atraumatic tip. The distal end of the catheter has an inflatable balloon coated with a proprietary coating containing the drug paclitaxel that facilitates the drug's transfer to the urethral wall upon inflation.	Control Treatment The control arm will be treated by a urethral dilation method considered to be best standard of care for the study site and subject. A control treatment may be either a rod, uncoated balloon or DVIU. Control Treatment: A control subject may be dilated with either a rod, uncoated balloon or DVIU until the desired result is reached, based on standard of care for the clinical site and treating physician
IPSS Percent Responder (50% Improvement in IPSS Score)	39 Participants	—

Adverse Events

Optilume Treatment

Serious events: 9 serious events

Other events: 51 other events

Deaths: 1 deaths

Control Treatment

Serious events: 8 serious events

Other events: 38 other events

Deaths: 0 deaths

Serious adverse events

Other adverse events

Other adverse events
Measure	Optilume Treatment n=79 participants at risk The treatment arm will be the Urotronic Optilume Drug Coated Balloon (DCB). Optilume Drug Coated Balloon (DCB): The Optilume Drug Coated Balloon (DCB) is a guidewire compatible catheter with a tapered atraumatic tip. The distal end of the catheter has an inflatable balloon coated with a proprietary coating containing the drug paclitaxel that facilitates the drug's transfer to the urethral wall upon inflation.	Control Treatment n=48 participants at risk The control arm will be treated by a urethral dilation method considered to be best standard of care for the study site and subject. A control treatment may be either a rod, uncoated balloon or DVIU. Control Treatment: A control subject may be dilated with either a rod, uncoated balloon or DVIU until the desired result is reached, based on standard of care for the clinical site and treating physician
Renal and urinary disorders Urethral Stenosis	11.4% 9/79 • Number of events 9 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.	41.7% 20/48 • Number of events 20 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.
Renal and urinary disorders Dysuria	8.9% 7/79 • Number of events 7 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.	2.1% 1/48 • Number of events 1 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.
Renal and urinary disorders Urinary Retention	7.6% 6/79 • Number of events 7 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.	8.3% 4/48 • Number of events 4 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.
Renal and urinary disorders Bladder Spasm	5.1% 4/79 • Number of events 4 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.	2.1% 1/48 • Number of events 2 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.
Infections and infestations Urinary Tract Infection	8.9% 7/79 • Number of events 16 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.	10.4% 5/48 • Number of events 8 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.
Infections and infestations Bacteriuria	6.3% 5/79 • Number of events 6 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.	4.2% 2/48 • Number of events 2 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.
Respiratory, thoracic and mediastinal disorders Cough	5.1% 4/79 • Number of events 4 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.	4.2% 2/48 • Number of events 2 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.
Respiratory, thoracic and mediastinal disorders Bronchitis	0.00% 0/79 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.	6.2% 3/48 • Number of events 3 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.
Injury, poisoning and procedural complications Post-Procedure Hematuria	11.4% 9/79 • Number of events 9 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.	4.2% 2/48 • Number of events 3 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.
Immune system disorders Hypersensitivity	0.00% 0/79 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.	6.2% 3/48 • Number of events 3 • 1 Year Adverse event collection began at the time of randomization. Subjects were queried about adverse events occuring since last contact at each study visit.

Additional Information

Vice President of Clinical Affairs

Urotronic, Inc

Phone: 763-285-7489

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place