Recommendations of the SUFU/AUGS/ICS Female Stress Urinary Incontinence Surgical Publication Working Group: A common standard minimum data set for the literature.

INTRODUCTION AND OBJECTIVES: Relevant, meaningful, and achievable data points are critical in objectively assessing quality, utility, and outcomes in female stress urinary incontinence (SUI) surgery. A minimum data set female SUI surgery studies was proposed by the first American Urological Association guidelines on the surgical management of female SUI in 1997, but recommendation adherence has been suboptimal. The Female Stress Urinary Incontinence Surgical Publication Working Group (WG) was created from members of several prominent organizations to formulate a recommended standard of study structure, description, and minimum outcome data set to be utilized in designing and publishing future SUI studies. The goal of this WG was to create a body of evidence better able to assess the outcomes of female SUI surgery. METHODS: The WG reviewed the minimum data set proposed in the 1997 AUA SUI Guideline document, and other relevant literature. The body of literature was examined in the context of the profound changes in the field over the past 25 years. Through a DELPHI process, a standard study structure and minimum data set were generated. Care was taken to balance the value of several meaningful and relevant data points against the burden of creating an excessively difficult or restrictive standard that would disincentivize widespread adoption and negatively impact manuscript production and acceptance. RESULTS: The WG outlined standardization in four major areas: (1) study design, (2) pretreatment demographics and characterization of the study population, (3) intraoperative events, and (4) posttreatment evaluation, and complications. Forty-two items were evaluated and graded as: STANDARD-must be included; ADDITIONAL-may be included for a specific study and is inclusive of the Standard items; OPTIMAL-may be included for a comprehensive study and is inclusive of the Standard and Additional items; UNNECESSARY/LEGACY-not relevant. CONCLUSIONS: A reasonable, achievable, and clinically meaningful minimum data set has been constructed. A structured framework will allow future surgical interventions for female SUI to be objectively scrutinized and compared in a clinically significant manner. Ultimately, such a data set, if adopted by the academic community, will enhance the quality of the scientific literature, and ultimately improve short and long-term outcomes for female patients undergoing surgery to correct SUI.

Recommendations of the SUFU/AUGS/ICS Female Stress Urinary Incontinence Surgical Publication Working Group: A Common Standard Minimum Data Set for the Literature.

INTRODUCTION AND OBJECTIVES: Relevant, meaningful, and achievable data points are critical in objectively assessing quality, utility, and outcomes in female stress urinary incontinence (SUI) surgery. A minimum data set female SUI surgery studies was proposed by the first American Urological Association guidelines on the surgical management of female SUI in 1997, but recommendation adherence has been suboptimal. The Female Stress Urinary Incontinence Surgical Publication Working Group (WG) was created from members of several prominent organizations to formulate a recommended standard of study structure, description, and minimum outcome data set to be utilized in designing and publishing future SUI studies. The goal of this WG was to create a body of evidence better able to assess the outcomes of female SUI surgery. METHODS: The WG reviewed the minimum data set proposed in the 1997 AUA SUI Guideline document, and other relevant literature. The body of literature was examined in the context of the profound changes in the field over the past 25 years. Through a DELPHI process, a standard study structure and minimum data set were generated. Care was taken to balance the value of several meaningful and relevant data points against the burden of creating an excessively difficult or restrictive standard that would disincentivize widespread adoption and negatively impact manuscript production and acceptance. RESULTS: The WG outlined standardization in four major areas: 1) study design, 2) pretreatment demographics and characterization of the study population, 3) intraoperative events, and 4) post-treatment evaluation, and complications. Forty-two items were evaluated and graded as: STANDARD - must be included; ADDITIONAL - may be included for a specific study and is inclusive of the Standard items; OPTIMAL - may be included for a comprehensive study and is inclusive of the Standard and Additional items; UNNECESSARY/LEGACY - not relevant. CONCLUSIONS: A reasonable, achievable, and clinically meaningful minimum data set has been constructed. A structured framework will allow future surgical interventions for female SUI to be objectively scrutinized and compared in a clinically significant manner. Ultimately, such a data set, if adopted by the academic community, will enhance the quality of the scientific literature, and ultimately improve short and long-term outcomes for female patients undergoing surgery to correct SUI.

The female urethral closure mechanism during physical stress.

The closure of the urethra under the condition of stress is the result of a reflex contraction of the urethral rhabdosphincter and pelvic floor muscles. This is likely induced by activity of the abdominal muscles due to a sudden increase in abdominal pressure. This reflex contraction with an increase of urethral pressure occurs a few milliseconds before an increase in intraabdominal pressure. The urethral pressure increase during stress is only possible with fixation of the urethra by the pubourethral ligaments (PUL), facilitating urethral kinking. The highest and most important increase in pressure and resistance occurs in the distal urethra due to this kinking of the urethra.

Evolving types of pudendal neuromodulation for lower urinary tract dysfunction.

Introduction: Sacral neuromodulation and posterior tibial nerve stimulation for lower urinary tract dysfunction (LUTD) and overactive bladder yield good and reliable results. However, neuromodulation research is continuously evolving because there is still need for more patient-friendly treatment options in the therapeutic management of LUTD. Pudendal neuromodulation (PNM) has been emerging as a promising alternative treatment option for the last few decades. The aim of this study is to review the current state of the art of PNM. Material and methods: A wide literature search was conducted in the field of PNM using Medline through the PubMed database and Elsevier using the Scopus database; a critical review of the results was then carried out. PNM has been studied in its various possible aspects: percutaneous PNM, transrectal/transvaginal PNM, and both percutaneous and transcutaneous dorsal genital nerve stimulation. Results: Each technique was found to result in promising improvements in different clinical outcomes, with some trials reporting even better results than sacral neuromodulation. Conclusions: As a result of a comparison between the various PNM techniques with both sacral neuromodulation and posterior tibial nerve stimulation, we think that PNM should be seen as seriously promising, and we believe it will expand the treatment options for overactive bladder. Even though several studies accordingly showed PNM to be safe and effective, a systematic review and meta-analysis were not feasible. PNM in its various techniques is a promising treatment for LUTD. Nevertheless, further research is needed to include it in treatment algorithms.

A prospective study to assess the effectiveness and safety of the BlueWind System in the treatment of patients diagnosed with urgency urinary incontinence.

BACKGROUND: Overactive bladder (OAB) affects one in six adults in Europe and the United States and impairs the quality of life of millions of individuals worldwide. When conservative management fails, third-line treatments including tibial neuromodulation (TNM) is often pursued. TNM has traditionally been accomplished percutaneously in clinic. OBJECTIVE: A minimally invasive implantable device activated by a battery-operated external wearable unit has been developed for the treatment of urgency urinary incontinence (UUI), mitigating the burden of frequent clinic visits and more invasive therapies that are currently commercially available. METHODS: A prospective, multicenter, single-arm, open-label, pivotal study evaluated the safety and effectiveness of the device in adult females with UUI (i.e., wet OAB) (BlueWind Implantable Tibial Neuromodulation [iTNM] system; IDE number #G200013; NCT03596671). Results with the device were previously published under the name RENOVA iStim, which has been since renamed as the Revi™ System. Approximately 1-month post-implantation of the device, participants delivered therapy at their convenience and completed a 7-day voiding diary before visits 6- and 12-months post-treatment initiation. The primary efficacy and safety endpoints were the proportion of responders to therapy ( ≥ 50% improvement on average number of urgency-related incontinence episodes) and incidence of adverse events from implantation to 12-month post-activation. RESULTS: A total of 151 participants, mean age 58.8 (SD: 12.5), were implanted; 144 and 140 completed the 6- and 12-month visits, respectively. The participants demonstrated mean baseline of 4.8 UUI/day (SD 2.9) and 10 voids/day (SD 3.3). Six and 12-months post-activation, 76.4% and 78.4% of participants, respectively, were responders to therapy in an intent-to-treat analysis. Of the 139 participants with completed 12-month diaries, 82% were responders, 50% were classified as "dry" (on at least 3 consecutive diary days), and 93.5% of participants reported that their symptoms improved. No implanted participant experienced an SAE related to the procedure or device. CONCLUSIONS: iTNM, delivered and powered by a patient-controlled external wearable communicating with an implant, demonstrated clinically meaningful and statistically significant improvement in UUI symptoms and a high safety profile. This therapy highlights the value of patient-centric therapy for the treatment of UUI.

Results at 1 Year from SATURN, A European, Prospective, Multicenter Registry for Male Stress Urinary Incontinence Surgery.

BACKGROUND AND OBJECTIVE: The European, prospective, multicenter SATURN registry was developed to analyze surgical devices for male stress urinary incontinence. The primary objective is the cure rate during follow-up. METHODS: Efficacy, complications, patient-reported outcomes, and prognostic factors are being analyzed at various intervals during 10-yr follow-up. The results at 1-yr follow-up are presented here. KEY FINDINGS AND LIMITATIONS: The cohort included 1046 patients (mean age 70 yr) from 28 centers in nine countries. The main cause of incontinence was radical prostatectomy (83.5%), followed by radiotherapy (4.5%), endourological procedures (9.7%), neurogenic conditions (1.0%), and trauma (0.2%). Some 19.5% of the patients underwent at least one incontinence procedure before registry inclusion. A baseline pad test was performed in 64% of the patients (mean 525 g, range 3.5-3600), urodynamics in 66%, and cystoscopy in 80%. The main implants used were AMS800 (n = 684) and Advance (n = 210) devices, followed by Atoms (n = 63) Victo/Plus (n = 33), ProACT (n = 30), and others (n = 24). A total of 896 patients had 1-yr follow-up data, of whom 164 completed a 1-yr pad test. Self-reported complete incontinence rates at baseline by device were as follows: Advance, 17%; other slings, 33%; ProACT, 0%; AMS800, 49%; other sphincter prosthesis, 100%; and overall group, 44%. The corresponding 1-yr self-reported continence rates were 73%, 37%, 50%, 76%, 11%, and 68%. Some 32% of the patients were still incontinent. Overall, 132 patients had at least one revision. Among the 110 patients with an artificial urinary sphincter (AUS), 122 revisions were performed, while there were 29 revisions for the 22 patients with a sling or ProACT device. International Consultation on Incontinence Questionnaire Short Form and EuroQol 5-dimensions 5-levels scores improved with all devices. CONCLUSIONS AND CLINICAL IMPLICATIONS: AUS implants are used in cases with more severe incontinence and are associated with better outcomes but more revisions than the alternatives. Patients report that every improvement is important. Choices for procedures should be made on the basis of these considerations. PATIENT SUMMARY: We collected data from 29 urology departments in Europe on surgical treatments for patients who suffer from incontinence during exercise, sneezing, and coughing. Results after 1 year show that an artificial urinary sphincter has the best outcomes overall and for patients with heavy urine loss. However, this surgery also requires more revisions. Patients report that every improvement in continence is important to them.

Quantification of Aging-Related Decreases in Sensory Innervation of the Bladder Trigone in Rats.

PURPOSE: The prevalence of lower urinary tract symptoms (LUTS), characterized by problems regarding storage and/or voiding of urine, is known to significantly increase with age. Effective communication between the lower urinary tract and the central nervous system (CNS) is essential for the optimal function of this system, and heavily relies on the efficient interaction between the bladder urothelium and the afferent nerve fibers situated in close proximity to the urothelium within the lamina propria. METHODS: We aimed to quantify aging-related differences in the expression of calcitonin gene-related peptide (CGRP, an established marker for sensory nerve fibers) in the trigonal mucosal layers of young (3-4 months) and aged (25-30 months) rats. We evaluated trigonal tissue from 3 animals per age group. Tissue was serially sectioned at 10 µm and stained for CGRP. Images were taken along the full length of the tissue. For each image we computed the total CGRP-positive area (µm2) and the median value for each animal was used for further analysis. RESULTS: Upon statistical analysis the aged rats show a significantly lower CGRP-positive area compared to young rats (P=0.0049). These results indicate that aging has a negative effect on the area of CGRP-positive signal in the trigone. CONCLUSION: The structural and functional integrity of the sensory web in the trigonum of rats is negatively affected by the aging process, potentially leading to impaired communication between the bladder urothelium the CNS. Consequently, these perturbations in the sensory system may contribute to the pathogenesis or exacerbation LUTS.

Quality of Life and Treatment Modalities in Patients with Interstitial Cystitis: The Patients' Perspective.

BACKGROUND: Quality of life (QoL)-based outcomes are hardly incorporated into interstitial cystitis/bladder pain syndrome (IC/BPS) guidelines, because studies are limited and outdated. Therefore, guidelines might not reflect the current clinical situation accurately. Secondly, guidelines suggest using a multimodal approach for BPS/IC management, but data on the patient-perceived efficacy of these therapies are limited. The aim of this study is to investigate the perception of IC/BPS patients of their QoL, to determine which treatments they have received, and to examine how they evaluate the efficacy of these various (alternative) therapies. METHODS: A quantitative retrospective database evaluation was performed, with data from an existing IC/BPS patient survey (n = 217) that was conducted in 2021. This survey contained QoL data based on validated questionnaires such as EQ-5D 5L. RESULTS: The QoL of patients is affected significantly by IC/BPS. This is evident from the various affected domains on the EQ-5D 5L. The symptom severity was negatively affected by a delay in diagnosis, and there were clear differences in QoL domains between females and males. Secondly, coagulation therapy and intravesical glycosaminoglycan (GAG) therapy were most appreciated by patients. Other (alternative) treatments were commonly utilized, although some had doubtful results and high discontinuation rates. CONCLUSION: QoL is considerably impaired in IC/BPS patients. The diverse responses and adherence to various treatments warrant a personalized approach (phenotype-oriented therapy). To achieve QoL improvement, it is important to incorporate the patient's perspective in treatment guidelines.

Bladder pain syndrome AKA interstitial cystitis - a condition with severe unmet medical need: an exploration of brimapitide as a potential treatment opportunity.

PURPOSE OF REVIEW: The purpose of this article is to present recent findings of KU002 (brimapitide) as a novel treatment option for interstitial cystitis/bladder pain syndrome (IC/BPS). RECENT FINDINGS: IC/BPS is a complex and poorly understood heterogeneous syndrome, with many burdensome symptoms that severely affect patients' quality of life. Treatment options beyond conservative and nonpharmacologic approaches remain limited, and there is an unmet medical need for effective medical treatments. While there are multiple ongoing clinical trials in this area, only a few explore new treatment options. This article summarizes current ongoing development and reports the findings of one such trial. SUMMARY: In a phase 1/2a exploratory trial, intravesical instillation of brimapitide confirmed local action while eliciting in minimal systemic exposure, resulting in a promising and favorable safety profile. Efficacy exploration suggests that brimapitide reduces pain, improves signs and symptoms of IC/BPS and improves the general wellbeing of the study participants.

Current position of neuromodulation for bladder pain syndrome/interstitial cystitis.

PURPOSE OF REVIEW: Despite established effectiveness in overactive bladder and nonobstructive retention, neuromodulation's application in interstitial cystitis/bladder pain syndrome (IC/BPS) remains a topic of ongoing research. The purpose of this article is to review recent developments in neuromodulation as treatment of IC/BPS offering guidance for healthcare practitioners dealing with IC/BPS cases. RECENT FINDINGS: Recent research underlines the promising role of sacral, tibial and pudendal neuromodulation in management of IC/BPS symptoms. Studies reveal encouraging outcomes, particularly in alleviating urgency and frequency symptoms. However, while urgency and frequency symptoms tend to improve, comprehensive pain relief remains a challenge. Percutaneous tibial nerve stimulation (PTNS) and transcutaneous tibial nerve stimulation (TTNS) stand out due to their minimal invasive nature. Existing literature points to the need for larger prospective studies with extended follow-up periods to validate the efficacy and sustainability of neuromodulation. SUMMARY: Neuromodulation is a promising treatment modality for refractory IC/BPS. Due to the minimal invasive nature, they should be tried before rigorous surgery. However, the limited quantity of available data and the variability in pain relief outcomes necessitate cautious interpretation. The review emphasizes the need for further research.

What Is in the Pipeline on Investigational Neuromodulation Techniques for Lower Urinary Tract Dysfunction: A Narrative Review.

OBJECTIVES: Overactive bladder (OAB) affects millions of patients worldwide. Its treatment is challenging but improves the patient's quality of life. Besides standard techniques for neuromodulation (sacral and pudendal neuromodulation and posterior tibial nerve stimulation), several new techniques have been investigated to treat symptoms of refractory OAB. The purpose of the present review is to outline the state of the art of new neuromodulation techniques for lower urinary tract dysfunction (LUTD). MATERIALS AND METHODS: In March 2023, a comprehensive MEDLINE, EMBASE, and Scopus search was carried out (keywords: LUTD, new technologies, neuromodulation, LUTS, OAB, painful bladder syndromes, etc). Articles were included according to inclusion (randomized controlled trials, prospective trials, large retrospective studies) and exclusion (case reports, outcomes not clearly expressed in full text, animal studies) criteria. The reference lists of the included studies also were scanned. Both adult and pediatric populations were included, in addition to both neurogenic and nonneurogenic OAB. A narrative review was then performed. RESULTS: Peroneal neuromodulation, transcutaneous electrical nerve stimulation, magnetic nerve stimulation, and parasacral transcutaneous neuromodulation are the most studied investigative techniques and were shown to yield promising results in treating OAB symptoms. Most studies showed promising results even in the complex scenarios of patients with OAB refractory to standard treatments. Comparing investigational techniques with standard of care and their respective clinical outcomes and safety profiles, and confronting their pros and cons, we reasonably believe that once such treatment modalities are further developed, they could play a role in the OAB treatment algorithm. CONCLUSIONS: Although the described neuromodulation techniques are being intensely studied, the available results are not yet sufficient for any guidelines to recommend their use.

SATURN: A European, Prospective, Multicentre Registry for Male Stress Urinary Incontinence Surgery.

Surgery for male incontinence with artificial urinary sphincters and slings (SATURN) is a prospective, multicentre registry (observational cohort) for male stress urinary incontinence surgery to collect prospective data from multiple European centres and surgeons, to evaluate the short- and long-term success and the impact on quality of life.

The Burden of Urinary Tract Infections on Quality of Life and Healthcare in Patients with Interstitial Cystitis.

BACKGROUND: Interstitial cystitis/bladder pain syndrome (IC/BPS) patients are more susceptible to urinary tract infections (UTIs), likely worsening pre-existing symptoms. However, this receives limited attention in guidelines. This study aimed to explore the burden of UTIs on IC/BPS patients' quality of life and their healthcare. METHODS: Two quantitative retrospective database studies were conducted in cystoscopically proven IC/BPS patients: one compiled existing patient survey data (n = 217) from July 2021 to examine physical and emotional UTI burden, and the other used a patient file database (n = 100) from January 2020 to May 2022, focusing on UTI prevalence, healthcare use, urine cultures and antibiotic resistance. RESULTS: A delay in diagnosis was seen in 70% of patients, due to doctors confusing IC/BPS symptoms with UTIs. The UTI prevalence was over 50%; these patients also report anxiety for new UTIs (70%) and worsening of IC/BPS symptoms (60%). Additionally, for UTI+ patients, healthcare consumption was significantly increased in both studies. Antibiotic resistance (80% of cultures) and prophylactic antibiotic use were common. CONCLUSIONS: These findings highlight the burden of UTIs on quality of life in IC/BPS patients and the healthcare system. These results emphasize the need for improved UTI guidelines concerning diagnosis, management and prevention for IC/BPS patients to improve quality of life and care.

Effect of bladder outlet procedures on urodynamic assessments in men with an acontractile or underactive detrusor: A systematic review and meta-analysis.

OBJECTIVE: To review the effect of bladder outlet procedures on urodynamic outcomes and symptom scores in males with detrusor underactivity (DU) or acontractile detrusors (AD). MATERIALS AND METHODS: We performed a systematic review and meta-analysis of research publications derived from PubMed, Embase, Web of Science, and Ovid Medline to identify clinical studies of adult men with non-neurogenic DU or AD who underwent any bladder outlet procedure. Outcomes comprised the detrusor pressure at maximum flow (Pdet Qmax ), maximum flow rate (Qmax ), international prostate symptom score (IPSS), and quality of life (QoL). This study is registered under PROSPERO CRD42020215832. RESULTS: We included 13 studies of bladder outlet procedures, of which 6 reported decreased and 7 reported improved Pdet Qmax after the procedure. Meta-analysis revealed an increase in the pooled mean Pdet Qmax of 5.99 cmH2 0 after surgery (95% CI: 0.59-11.40; p = 0.03; I2 95%). Notably, the Pdet Qmax improved in all subgroups with a preoperative bladder contractility index (BCI) <50 and decreased in all subgroups with a BCI ≥50. All studies reported an improved Qmax after surgery, with a pooled mean difference of 5.87 mL/s (95% CI: 4.25-7.49; I2 93%). Only three studies reported QoL, but pooling suggested significant improvements after surgery (mean, -2.41 points; 95% CI: -2.81 to -2.01; p = 0.007). All seven studies reporting IPSS demonstrated improvement (mean, -12.82; 95% CI: -14.76 to -10.88; p < 0.001). CONCLUSIONS: This review shows that Pdet Qmax and Qmax increases after surgical bladder outlet procedures in men with DU and AD. Bladder outlet procedures should be discussed as part of the shared decision-making process for this group. The evidence was of low to very low certainty.

Differences in the Urinary Microbiome of Patients with Overactive Bladder Syndrome with and without Detrusor Overactivity on Urodynamic Measurements.

INTRODUCTION: It has been hypothesized that the urinary microbiome might play an important role in OAB. Studies have been conducted on the association between OAB symptoms and the microbiome, although a possible causality still has to be determined. MATERIAL AND METHODS: In this study, 12 female patients, ≥18 years of age, with 'OAB DO+' and 9 female patients with 'OAB DO-' were included. Patients were excluded if they met one of the following exclusion criteria: bladder tumors and previous bladder operations; sacral neuromodulation; injection of Botox in the bladder; and TOT or TVT operations. Urine samples were collected and stored with patient informed consent and with the approval of the Hospital Ethical Review Board (Arnhem-Nijmegen). All OAB patients underwent urodynamics before collecting urine samples, and the diagnosis of detrusor overactivity was confirmed by two individual urologists. In addition, samples from 12 healthy controls who did not undergo urodynamic evaluation were analyzed. The 16S rRNA V1-V2 region amplification and gel electrophoresis were used to determine the microbiota. RESULTS: 12 of the OAB patients had DO shown on their urodynamic studies; the remaining 9 patients had a normoactive detrusor on their urodynamic measurements. Overall, there were no substantial differences among the demographic characteristics of the subjects. The samples were classified as the following: 180 phyla, 180 classes, 179 orders, 178 families, 175 genera, and 138 species. The least commonly observed phyla were Proteobacteria, with an average presence of 10%, followed by Bacteroidetes with 15%, Actinobacteria with 16%, and Firmicutes with 41%. Most of the sequences could be classified according to the genus level for each sample. DISCUSSION: Significant differences were observed in the urinary microbiome of patients with overactive bladder syndrome who have detrusor overactivity on urodynamics compared to OAB patients without detrusor overactivity and matched controls. OAB patients with detrusor overactivity have a significantly less diverse microbiome and show a higher proportion of Lactobacillus, particularly Lactobacillus iners. The results imply that the urinary microbiome could be involved in the pathogenesis of a specific phenotype of OAB. The urinary microbiome could be a new starting point to study the causes and treatments of OAB.

The Maximal Urethral Pressure at Rest and during Normal Bladder Filling Is Only Determined by the Activity of the Urethral Smooth Musculature in the Female.

The aim of this opinion paper is to determine the entities that define the maximal urethral pressure (MUP) during rest and during bladder filling that is needed to guarantee continence in females. For the development of this opinion, the literature was searched for via the Pubmed database and historic sources. Animal studies indicate that the maximal urethral pressure is determined by the smooth muscle activity in the mid-urethra. Additionally, during increased smooth muscle tone development, the largest sympathetic responses are found in the middle part of the urethra. This could be confirmed in human studies that are unable to find striated EMG activity in this area. Moreover, the external urethral striated sphincter is situated at the distal urethra, which is not the area with the highest pressure. The external urethral sphincter only provides additional urethral pressure in situations of exertion and physical activity. From a physics point of view, the phasic pressure of the external striated sphincter at the distal urethra cannot be added to the tonic pressure generated by the smooth muscle in the mid-urethra. The assertion that mid-urethral pressure is the result of different pressure forces around the urethra, including that of the external striated sphincter, is not supported by basic research evidence combined with physical calculation and should therefore be considered a misconception in the field of functional urology.

Study protocol of a multicentre double-blind RCT, comparing a traditional RCT with an aggregated N-of-1 trial: GAG therapy Efficacy Trial Solution for Bladder pain syndrome/Interstitial cystitis (GETSBI study).

INTRODUCTION: Obtaining level 1 evidence on efficacy of glycosaminoglycan (GAG) therapy is difficult, due to low incidence of bladder pain syndrome/interstitial cystitis (BPS/IC) and heterogeneous symptoms experienced by patients with BPS/IC. Currently, because of a lack of high-grade evidence, the recommendation for applying GAG therapy in most guidelines is 'low grade'. An aggregated N-of-1 trial is a multicrossover design that yields similar level 1 evidence as a traditional randomised controlled trial (RCT), while requiring far less patients. The goal of this study is to investigate the efficacy of intravesical GAG therapy (Ialuril) for patients with BPS/IC with Hunner lesions using a dual RCT and aggregated N-of-1 trial design to obtain level 1 evidence. METHODS AND ANALYSIS: The GETSBI study is a double-blind multidesign multicentre randomised placebo-controlled study to assess the short-term and long-term efficacy of hyaluronic acid (1.6%) + chondroitin sulfate (2%) therapy (Ialuril Prefill, IBSA, Goodlife) in patients with symptomatic BPS/IC with Hunner lesions. It starts as a standard RCT (n=80), but continues as an aggregated N-of-1 trial. There are three parallel arms, receiving blinded treatment for three periods (1 x/week for 6 weeks, ratio placebo to intervention in periods of 2:1). Followed by an open prospective part for the long-term efficacy. The primary study outcome is the maximum bladder pain experienced in the last 3 days measured using the visual analogue pain scale (0-10).This study is a collaboration with the Dutch government and will deliver evidence for the decision to reimburse the therapy. Furthermore, this multidesign study will allow us to compare the two main methods to evaluate applicability for future study designs for BPS/IC research. ETHICS AND DISSEMINATION: Ethical approval was given by METC Oost-Nederland, file number: 2020-7265, NL-number: NL76290.091.20. Findings from this study will be disseminated via publication, reports and conference presentations. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov identifier (NCT number): NCT05518864.