Cystoscopic RADA16 (PuraStat) for Persistent Severe Haematuria Secondary to Radiation Cystitis: A Prospective Two-centre Study

Cystoscopic RADA16 (PuraStat) for Persistent Severe Haematuria Secondary to Radiation Cystitis: A Prospective Two-centre Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Cystoscopic RADA16 (PuraStat) for Persistent Severe Haematuria Secondary to Radiation Cystitis: A Prospective Two-centre Study Petre Ilie, Ruth Doherty, Anne Carrie, Omar Al Kadhi, Claudiu Tanase, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9284350/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 10 You are reading this latest preprint version Abstract Background and Objective Haemorrhagic radiation cystitis is a challenging complication of pelvic radiotherapy, with limited high-quality evidence to guide management and no established standard of care. We evaluated the real-world efficacy and safety of intravesical RADA16 (PuraStat) for the treatment of persistent severe haematuria secondary to radiation cystitis. Methods This prospective observational study included patients with clinically significant haematuria following radiotherapy, treated with intravesical RADA16 across two NHS Trusts. The primary outcome was resolution of visible haematuria. Secondary outcomes included healthcare utilisation (hospital admissions, length of stay, emergency department attendances) and safety. Patients were followed for a minimum of 90 days. Key Findings and Limitations Ten patients (mean age 79.6 yr; 90% male) were included. Nine of ten patients had complete resolution of macroscopic haematuria during follow-up. One patient reported minimal, self-limiting haematuria occurring intermittently. No procedure-related adverse events were observed. Unplanned healthcare utilisation was reduced to zero in all patients following treatment. Follow-up cystoscopic assessment suggested improvement in bladder lesions. Limitations include the small sample size, single-arm design, and limited follow-up in some patients. Conclusions and Clinical Implications Intravesical RADA16 appears to be a safe and feasible treatment for haemorrhagic radiation cystitis and was associated with resolution of haematuria in the majority of patients and elimination of unplanned hospital attendances. These findings support further evaluation in larger, controlled studies to confirm efficacy, durability, and optimal treatment protocols. Patient Summary: We observed patients undergoing a new treatment for bleeding in the bladder that can occur after radiotherapy. Most patients stopped having visible bleeding after treatment, and none needed to return to hospital unexpectedly. This treatment may offer a simple and safe alternative to more invasive procedures, but larger studies are needed to confirm these results. RADA16 haemoragic cystitis radiation cystitis cystitis haemoragic radiation cystitis PuraStat PuraBond Take Home Message In a prospective two-centre study with protocolised 90-day follow-up, cystoscopic application of RADA16 self-assembling peptide hydrogel was associated with resolution of macroscopic haematuria in 9/10 patients and elimination of haematuria-related emergency attendances, admissions, transfusions, and inpatient days after treatment. What does the study add? This prospective multicentre study provides real-world evidence supporting the use of intravesical RADA16 (PuraStat) as a minimally invasive treatment for haemorrhagic radiation cystitis. It demonstrates resolution of macroscopic haematuria in the majority of patients, with no treatment-related adverse events. Treatment was also associated with complete elimination of unplanned healthcare utilisation. These findings suggest that RADA16 may represent a safe and accessible alternative to more invasive or resource-intensive therapies. Introduction Haemorrhagic radiation cystitis is a severe and often delayed complication of pelvic radiotherapy, characterised by bleeding from a fragile, vascularly compromised bladder mucosa. Management remains challenging, with limited high-quality evidence to guide treatment and no established standard of care, and many patients ultimately requiring multimodal therapy [ 1 ]. Current treatment strategies typically escalate from conservative to more invasive approaches, including urinary diversion with or without cystectomy, with significant implications for patient quality of life. RADA16 (PuraStat) is a synthetic self-assembling peptide hydrogel designed to achieve local haemostasis. It has been used successfully in endoscopic settings, including the management of gastrointestinal bleeding and radiation-induced rectal bleeding [ 2 ]. The primary aim of this observational study was to evaluate the real-world efficacy of intravesical RADA16 (PuraStat) in the management of severe persistent haematuria secondary to radiation cystitis across NHS Trusts. The secondary aim was to assess the safety profile of this intervention. Materials (Patients) and Methods This was a prospective observational study evaluating patients undergoing intravesical RADA16 (PuraStat) for persistent severe haematuria secondary to radiation cystitis. Patient selection Inclusion and exclusion criteria are summarised in Table 1. Eligible patients were aged >18 years, had completed pelvic radiotherapy >6 months previously, and had an endoscopically confirmed diagnosis of radiation cystitis characterised by friable telangiectasia, mucosal pallor, and oedema. Patients were required to have clinically significant haematuria (defined as at least weekly visible haematuria for ≥3 months, with or without anaemia) and a negative upper urinary tract evaluation (CT intravenous urogram) to exclude alternative causes. Patients were excluded if they were unable to undergo cystoscopic evaluation, had another untreated cause of haematuria, or had received previous PuraStat treatment for radiation cystitis. Clinical pathway and data collection All patients had experienced at least one hospital admission within the preceding 3 months requiring bladder irrigation, clot evacuation, and/or cystoscopic diathermy. Patients with persistent haematuria delaying discharge or requiring readmission were offered intravesical RADA16. Clinical data were collected for the 3 months before and after treatment, including haemoglobin levels, number of hospital admissions, total length of stay, and number of emergency department attendances. Macroscopic haematuria severity was assessed using a five-grade visual scale (Grades I–V) as described by Stout et al. [3]. Procedure and treatment protocol RADA16 was initially administered as an outpatient procedure using flexible cystoscopy under local anaesthesia, employing an air cystoscopy technique as previously described by Ilie et al. [4]. Where flexible cystoscopy was not sufficient, treatment was subsequently performed using rigid cystoscopy under general anaesthesia. The volume of RADA16 administered was recorded for each application. A planned reassessment cystoscopy was performed at 30 days, with repeat application if residual lesions were identified. If the bladder mucosa appeared healed, no further treatment was administered. For patients requiring repeat treatment, a further cystoscopic evaluation was performed at 2 months, with a maximum of three applications in total. Outcome measures The primary outcome was resolution of visible haematuria, assessed by patient report and corroborated by review of hospital electronic records. Secondary outcomes included healthcare utilisation, defined by hospital admissions, length of stay, and emergency department attendances. Ethics The study received national ethical approval from the REC London – Dulwich Research Ethics Committee (REC reference 23/LO/0998; IRAS ID 336909). One participating centre received RADA16 free of charge; however, study design, data collection, analysis, and reporting were conducted independently by the investigators. The study is reported in accordance with the STROBE guidelines. Results We report the first 10 patients enrolled in the study with a minimum follow-up of 90 days. Patient age ranged from 69 to 89 years, with a mean age of 79.6 years (SD 5.7). Nine patients were male and one was female. Nine patients underwent the procedure under local anaesthesia using flexible cystoscopy. In one patient, flexible cystoscopy was poorly tolerated following multiple prior catheterisations and bladder washouts; treatment was therefore completed at a later stage using rigid cystoscopy under spinal anaesthesia. A second patient required a planned optical urethrotomy at the second visit because of a urethral stricture identified at the initial procedure; this intervention was performed under general anaesthesia. No further applications were required in this patient, and the third cystoscopic assessment was completed under local anaesthesia. All patients except one were managed as outpatients, with no failed discharges or readmissions. One 84-year-old patient with multiple comorbidities and Grade V haematuria underwent treatment while already an inpatient. Two patients, including the female patient, had previously received radiotherapy for bladder cancer; the remaining eight had received radiotherapy for prostate cancer. Of these, one had brachytherapy, one had salvage radiotherapy after robot-assisted radical prostatectomy, and six had primary radiotherapy. At baseline, haematuria grade was I in two patients, II in three, III in two, and V in three. Baseline haemoglobin ranged from 7.8 to 13.9 g/dL, with a mean of 11.59 g/dL. Haemoglobin was not measured routinely as part of the study protocol and was recorded only when blood tests were performed for clinical reasons. At 3 months, haemoglobin was available for three patients and was within the normal range in all cases (13.3, 13.4, and 13.4 g/dL). The volume of RADA16 administered ranged from 3 to 6 ml, depending on the number and extent of lesions identified. Safety No procedure-related complications were identified during the study. One patient developed urinary retention following the procedure and successfully passed a trial without catheter after 1 week. The same patient later experienced voiding difficulty requiring a temporary catheter insertion after the final flexible cystoscopic assessment, at which no RADA16 was administered; this was considered unrelated to the treatment. Primary outcome Nine of ten patients had no subsequent macroscopic haematuria during the follow-up period, based on patient report corroborated by review of hospital electronic records. One patient reported minimal, self-limiting visible haematuria occurring approximately once weekly after defecation. Secondary outcome: healthcare utilisation In the 3 months before treatment, patients required a mean of 3.4 hospital attendances (SD 3.2), 2.9 emergency department attendances (SD 3.0), and 5.1 inpatient days (SD 4.8). The mean preoperative transfusion requirement was 0.5 units (SD 0.8). During the postoperative follow-up period, unplanned healthcare utilisation was reduced to zero in all patients. Follow-up ranged from 3 to 15 months, with a mean duration of 8.4 months (SD 3.6). Nine patients remained free of recurrent macroscopic haematuria throughout follow-up. One patient, who had been referred as a last-resort option after consenting to cystectomy, continued to report minimal, self-limiting symptoms approximately once weekly after defecation. His radiotherapy had been more recent than in other patients, and bleeding originated predominantly from the prostatic urethra, making application of RADA16 under air cystoscopy more technically challenging. He was the only patient requiring general anaesthesia for treatment. At 15 months of follow-up, he had required no further intervention for haematuria after three applications of RADA16, and his haemoglobin at 3 months had normalised from a baseline value of 7.8 g/dL. Our previously reported case treated with this technique also remained symptom-free, with no further unplanned hospital attendances at 3 years of follow-up [5]. Discussion Persistent or recurrent clinically significant haematuria following radiation cystitis remains a challenging condition to manage. Multiple therapeutic options have been proposed, including alum irrigation, hyaluronic acid and other intravesical agents, hyperbaric oxygen therapy (HBOT), and sodium pentosan polysulfate, with variable success and, in some cases, significant side effects. In refractory or life-threatening cases, more invasive approaches such as arterial embolization, intravesical formalin, or urinary diversion with or without cystectomy may be required [ 6 ]. HBOT is the most extensively studied treatment for radiation-induced haemorrhagic cystitis, with reported partial or complete response rates of up to 84% and evidence of durable benefit [ 7 ]. However, treatment typically requires a prolonged course, with patients requiring an average of 33 treatments, and is associated with complications including barotrauma, barotraumatic otitis in 6% of participants, and visual disturbances in 1%. In the present pilot study, we specifically selected patients with clinically significant haematuria, representing a population with substantial unmet clinical need. Notably, one patient had already consented to cystectomy and urinary diversion prior to enrolment, underscoring the severity of disease in this cohort. We observed no treatment-related adverse events following intravesical RADA16 administration. Treatment was associated with resolution of visible haematuria in nine out of ten patients, together with endoscopic improvement in radiation-induced bladder lesions. The proposed mechanism of RADA16, promoting haemostasis and mucosal regeneration through self-assembling peptide scaffolding, may explain the rapid symptomatic and endoscopic improvement observed. RADA16 (PuraStat) is a synthetic self-assembling peptide hydrogel that forms a nanofibre scaffold upon contact with physiological fluids, enabling local haemostasis. It has been used successfully in endoscopic settings, including the management of gastrointestinal bleeding and radiation-induced rectal bleeding [ 2 ]. Its ability to control capillary oozing and support tissue healing provides a plausible explanation for the clinical effects observed in this cohort. These findings informed our protocol of reassessment at three months, with consideration of repeat treatment even in the absence of recurrent haematuria. An additional advantage of this technique is its feasibility as an outpatient procedure under local anaesthesia, which is particularly relevant given the comorbidity burden in this patient population. Compared with HBOT, which requires multiple sessions over several weeks, this approach may offer a more accessible and less resource-intensive alternative. This study has important limitations . It represents a small, single-arm pilot study including only ten patients, without a comparator group. While the observed clinical and endoscopic improvements are encouraging, these findings should be interpreted with caution. Further studies are required to assess the durability of response, determine the optimal number of treatment applications, and identify patient populations at risk of recurrence. Conclusions Intravesical RADA16 appears to be a safe and feasible treatment for haemorrhagic radiation cystitis, deliverable via flexible cystoscopy under local anaesthesia. In this pilot cohort, treatment was associated with resolution of visible haematuria in the majority of patients, no unplanned hospital attendances, and no observed treatment-related adverse events. Larger controlled studies are needed to confirm efficacy, durability, and the optimal treatment regimen. Declarations Author Contribution Authorship formP.C.I.: Conceptualization, Methodology, Conducting a research and investigation process, specifically performing the experiments, or data/evidence collection, Validation, Formal analysis, Writing - Original DraftR.D.: Conducting a research and investigation process, specifically performing the experiments, or data/evidence collection, Writing - Review & EditingA.C.: Conducting a research and investigation process, specifically performing the experiments, or data/evidence collection, Writing - Review & EditingO.A.K.: Conducting a research and investigation process, specifically performing the experiments, or data/evidence collection, Writing - Review & EditingC.T.: Conducting a research and investigation process, specifically performing the experiments, or data/evidence collection, Writing - Review & EditingP.P.: Resources, Writing - Review & EditingC.R.: Conducting a research and investigation process, specifically performing the experiments, or data/evidence collection, Writing - Review & EditingF.R.: Management and coordination responsibility for the research activity planning and execution; Writing - Review & EditingT.D.: Management and coordination responsibility for the research activity planning and execution; Writing - Review & EditingL.S.: Conceptualization, Methodology, Validation, Formal analysis, Writing - Review & Editing References Browne, C., Davis, N. F., Mac Craith, E., Lennon, G. M., Mulvin, D. W., Quinlan, D. M., Mc Vey, Gerard P., Galvin, D. J., A Narrative Review on the Pathophysiology and Management for Radiation Cystitis, Advances in Urology, 2015, 346812, 7 pages, 2015. https://doi.org/10.1155/2015/346812 Andreyev J. Purastat therapy for bleeding radiation proctopathy. World J Gastrointest Endosc. 2026;18(1):112920. doi:10.4253/wjge.v18.i1.112920 Stout TE, Borofsky M, Soubra A. A visual scale for improving communication when describing gross hematuria. Urology. 2021;148:32–36. doi:10.1016/j.urology.2020.10.054 Ilie PC, Darwazeh H, Hemsworth L, Smith L. Technique used for PuraStat® application in urinary bladder bleeding. aju [Internet]. 2023 Nov. 26 [cited 2026 Mar. 23];3:1. Available from: https://atenajournals.com/index.php/aju/article/view/82 [4] Darwazeh H., Hemsworth L., Smith L., Ilie P. Cystoscopic application of PuraStat® in the treatment of radiation-induced haemorrhagic cystitis. Ann R Coll Surg Engl. 2024 doi: 10.1308/rcsann.2023.0034. Published online February 16. Goucher G, Saad F, Lukka H, Kapoor A. Canadian Urological Association Best Practice Report: Diagnosis and management of radiation-induced haemorrhagic cystitis. Can Urol Assoc J. 2019;13(2):15-23. doi:10.5489/cuaj.5788. Weiss JP, Mattei DM, Neville ED, et al. Primary treatment of radiation-induced haemorrhagic cystitis with hyperbaric oxygen: 10-year experience. J Urol. 1994;151:1514–7. doi: 10.1016/S0022-5347(17)35289-8. Tables Table 1. Patient inclusion and exclusion criteria Inclusion criteria Exclusion criteria Age ≥18 yr Age 6 months Inability to undergo complete cystoscopic evaluation Endoscopically confirmed radiation cystitis, characterised by friable telangiectasia, mucosal pallor, and oedema Other untreated cause of haematuria Clinically significant haematuria, defined as visible haematuria at least once weekly for ≥3 months, with or without anaemia Previous PuraStat treatment for radiation cystitis Negative upper urinary tract evaluation (CT IVU) Capacity to provide informed consent Table 2. Healthcare utilisation before and after treatment Outcome (per patient) Pre-treatment mean (SD) Pre-treatment median (IQR) Post-treatment mean (SD) Hospital attendances 3.4 (3.2) 3.0 (1.0–4.0) 0.0 (0.0) Emergency department visits 2.9 (3.0) 2.5 (0.2–4.0) 0.0 (0.0) Inpatient days 5.1 (4.8) 5.0 (0.8–8.0) 0.0 (0.0) Blood transfusions (units) 0.5 (0.8) 0.0 (0.0–0.8) 0.0 (0.0) Values are presented per patient over the 3-month periods before and after treatment. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 06 May, 2026 Reviews received at journal 20 Apr, 2026 Reviewers agreed at journal 20 Apr, 2026 Reviewers agreed at journal 20 Apr, 2026 Reviews received at journal 18 Apr, 2026 Reviewers agreed at journal 18 Apr, 2026 Reviewers invited by journal 07 Apr, 2026 Editor assigned by journal 02 Apr, 2026 Submission checks completed at journal 02 Apr, 2026 First submitted to journal 31 Mar, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9284350","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":619135312,"identity":"e0c4b445-62d3-4c8a-85cb-4bfcc7f61ce6","order_by":0,"name":"Petre 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21:23:07","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9284350/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9284350/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":106899584,"identity":"3bd42992-b169-4509-be45-edcc8bd0cc78","added_by":"auto","created_at":"2026-04-14 14:42:57","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":592697,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9284350/v1/3a2e9369-8c0b-4fe5-8fcd-aa75c4748a2c.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Cystoscopic RADA16 (PuraStat) for Persistent Severe Haematuria Secondary to Radiation Cystitis: A Prospective Two-centre Study","fulltext":[{"header":"Take Home Message ","content":"\u003cp\u003eIn a prospective two-centre study with protocolised 90-day follow-up, cystoscopic application of RADA16 self-assembling peptide hydrogel was associated with resolution of macroscopic haematuria in 9/10 patients and elimination of haematuria-related emergency attendances, admissions, transfusions, and inpatient days after treatment.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat does the study add?\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis prospective multicentre study provides real-world evidence supporting the use of intravesical RADA16 (PuraStat) as a minimally invasive treatment for haemorrhagic radiation cystitis. It demonstrates resolution of macroscopic haematuria in the majority of patients, with no treatment-related adverse events. Treatment was also associated with complete elimination of unplanned healthcare utilisation. These findings suggest that RADA16 may represent a safe and accessible alternative to more invasive or resource-intensive therapies.\u003c/p\u003e"},{"header":"Introduction","content":"\u003cp\u003eHaemorrhagic radiation cystitis is a severe and often delayed complication of pelvic radiotherapy, characterised by bleeding from a fragile, vascularly compromised bladder mucosa. Management remains challenging, with limited high-quality evidence to guide treatment and no established standard of care, and many patients ultimately requiring multimodal therapy [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Current treatment strategies typically escalate from conservative to more invasive approaches, including urinary diversion with or without cystectomy, with significant implications for patient quality of life.\u003c/p\u003e \u003cp\u003eRADA16 (PuraStat) is a synthetic self-assembling peptide hydrogel designed to achieve local haemostasis. It has been used successfully in endoscopic settings, including the management of gastrointestinal bleeding and radiation-induced rectal bleeding [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe primary aim of this observational study was to evaluate the real-world efficacy of intravesical RADA16 (PuraStat) in the management of severe persistent haematuria secondary to radiation cystitis across NHS Trusts. The secondary aim was to assess the safety profile of this intervention.\u003c/p\u003e"},{"header":"Materials (Patients) and Methods","content":"\u003cp\u003eThis was a prospective observational study evaluating patients undergoing intravesical RADA16 (PuraStat) for persistent severe haematuria secondary to radiation cystitis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003ePatient selection\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eInclusion and exclusion criteria are summarised in Table 1. Eligible patients were aged \u0026gt;18 years, had completed pelvic radiotherapy \u0026gt;6 months previously, and had an endoscopically confirmed diagnosis of radiation cystitis characterised by friable telangiectasia, mucosal pallor, and oedema. Patients were required to have clinically significant haematuria (defined as at least weekly visible haematuria for \u0026ge;3 months, with or without anaemia) and a negative upper urinary tract evaluation (CT intravenous urogram) to exclude alternative causes.\u003c/p\u003e\n\u003cp\u003ePatients were excluded if they were unable to undergo cystoscopic evaluation, had another untreated cause of haematuria, or had received previous PuraStat treatment for radiation cystitis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eClinical pathway and data collection\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll patients had experienced at least one hospital admission within the preceding 3 months requiring bladder irrigation, clot evacuation, and/or cystoscopic diathermy. Patients with persistent haematuria delaying discharge or requiring readmission were offered intravesical RADA16.\u003c/p\u003e\n\u003cp\u003eClinical data were collected for the 3 months before and after treatment, including haemoglobin levels, number of hospital admissions, total length of stay, and number of emergency department attendances.\u003c/p\u003e\n\u003cp\u003eMacroscopic haematuria severity was assessed using a five-grade visual scale (Grades I\u0026ndash;V) as described by Stout et al. [3].\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eProcedure and treatment protocol\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eRADA16 was initially administered as an outpatient procedure using flexible cystoscopy under local anaesthesia, employing an air cystoscopy technique as previously described by Ilie et al. [4]. \u0026nbsp;Where flexible cystoscopy was not sufficient, treatment was subsequently performed using rigid cystoscopy under general anaesthesia.\u003c/p\u003e\n\u003cp\u003eThe volume of RADA16 administered was recorded for each application. A planned reassessment cystoscopy was performed at 30 days, with repeat application if residual lesions were identified. If the bladder mucosa appeared healed, no further treatment was administered. For patients requiring repeat treatment, a further cystoscopic evaluation was performed at 2 months, with a maximum of three applications in total.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eOutcome measures\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe primary outcome was resolution of visible haematuria, assessed by patient report and corroborated by review of hospital electronic records. Secondary outcomes included healthcare utilisation, defined by hospital admissions, length of stay, and emergency department attendances.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eEthics\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study received national ethical approval from the REC London \u0026ndash; Dulwich Research Ethics Committee (REC reference 23/LO/0998; IRAS ID 336909). One participating centre received RADA16 free of charge; however, study design, data collection, analysis, and reporting were conducted independently by the investigators. The study is reported in accordance with the STROBE guidelines.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eWe report the first 10 patients enrolled in the study with a minimum follow-up of 90 days. Patient age ranged from 69 to 89 years, with a mean age of 79.6 years (SD 5.7). Nine patients were male and one was female.\u003c/p\u003e\n\u003cp\u003eNine patients underwent the procedure under local anaesthesia using flexible cystoscopy. In one patient, flexible cystoscopy was poorly tolerated following multiple prior catheterisations and bladder washouts; treatment was therefore completed at a later stage using rigid cystoscopy under spinal anaesthesia. A second patient required a planned optical urethrotomy at the second visit because of a urethral stricture identified at the initial procedure; this intervention was performed under general anaesthesia. No further applications were required in this patient, and the third cystoscopic assessment was completed under local anaesthesia.\u003c/p\u003e\n\u003cp\u003eAll patients except one were managed as outpatients, with no failed discharges or readmissions. One 84-year-old patient with multiple comorbidities and Grade V haematuria underwent treatment while already an inpatient.\u003c/p\u003e\n\u003cp\u003eTwo patients, including the female patient, had previously received radiotherapy for bladder cancer; the remaining eight had received radiotherapy for prostate cancer. Of these, one had brachytherapy, one had salvage radiotherapy after robot-assisted radical prostatectomy, and six had primary radiotherapy.\u003c/p\u003e\n\u003cp\u003eAt baseline, haematuria grade was I in two patients, II in three, III in two, and V in three. Baseline haemoglobin ranged from 7.8 to 13.9 g/dL, with a mean of 11.59 g/dL. Haemoglobin was not measured routinely as part of the study protocol and was recorded only when blood tests were performed for clinical reasons. At 3 months, haemoglobin was available for three patients and was within the normal range in all cases (13.3, 13.4, and 13.4 g/dL).\u003c/p\u003e\n\u003cp\u003eThe volume of RADA16 administered ranged from 3 to 6 ml, depending on the number and extent of lesions identified.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eSafety\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo procedure-related complications were identified during the study. One patient developed urinary retention following the procedure and successfully passed a trial without catheter after 1 week. The same patient later experienced voiding difficulty requiring a temporary catheter insertion after the final flexible cystoscopic assessment, at which no RADA16 was administered; this was considered unrelated to the treatment.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003ePrimary outcome\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNine of ten patients had no subsequent macroscopic haematuria during the follow-up period, based on patient report corroborated by review of hospital electronic records. One patient reported minimal, self-limiting visible haematuria occurring approximately once weekly after defecation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eSecondary outcome: healthcare utilisation\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn the 3 months before treatment, patients required a mean of 3.4 hospital attendances (SD 3.2), 2.9 emergency department attendances (SD 3.0), and 5.1 inpatient days (SD 4.8). The mean preoperative transfusion requirement was 0.5 units (SD 0.8). During the postoperative follow-up period, unplanned healthcare utilisation was reduced to zero in all patients.\u003c/p\u003e\n\u003cp\u003eFollow-up ranged from 3 to 15 months, with a mean duration of 8.4 months (SD 3.6). Nine patients remained free of recurrent macroscopic haematuria throughout follow-up. One patient, who had been referred as a last-resort option after consenting to cystectomy, continued to report minimal, self-limiting symptoms approximately once weekly after defecation. His radiotherapy had been more recent than in other patients, and bleeding originated predominantly from the prostatic urethra, making application of RADA16 under air cystoscopy more technically challenging. He was the only patient requiring general anaesthesia for treatment. At 15 months of follow-up, he had required no further intervention for haematuria after three applications of RADA16, and his haemoglobin at 3 months had normalised from a baseline value of 7.8 g/dL.\u003c/p\u003e\n\u003cp\u003eOur previously reported case treated with this technique also remained symptom-free, with no further unplanned hospital attendances at 3 years of follow-up [5].\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003ePersistent or recurrent clinically significant haematuria following radiation cystitis remains a challenging condition to manage. Multiple therapeutic options have been proposed, including alum irrigation, hyaluronic acid and other intravesical agents, hyperbaric oxygen therapy (HBOT), and sodium pentosan polysulfate, with variable success and, in some cases, significant side effects. In refractory or life-threatening cases, more invasive approaches such as arterial embolization, intravesical formalin, or urinary diversion with or without cystectomy may be required [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHBOT is the most extensively studied treatment for radiation-induced haemorrhagic cystitis, with reported partial or complete response rates of up to 84% and evidence of durable benefit [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. However, treatment typically requires a prolonged course, with patients requiring an average of 33 treatments, and is associated with complications including barotrauma, barotraumatic otitis in 6% of participants, and visual disturbances in 1%.\u003c/p\u003e \u003cp\u003eIn the present pilot study, we specifically selected patients with clinically significant haematuria, representing a population with substantial unmet clinical need. Notably, one patient had already consented to cystectomy and urinary diversion prior to enrolment, underscoring the severity of disease in this cohort. We observed no treatment-related adverse events following intravesical RADA16 administration. Treatment was associated with resolution of visible haematuria in nine out of ten patients, together with endoscopic improvement in radiation-induced bladder lesions.\u003c/p\u003e \u003cp\u003eThe proposed mechanism of RADA16, promoting haemostasis and mucosal regeneration through self-assembling peptide scaffolding, may explain the rapid symptomatic and endoscopic improvement observed. RADA16 (PuraStat) is a synthetic self-assembling peptide hydrogel that forms a nanofibre scaffold upon contact with physiological fluids, enabling local haemostasis. It has been used successfully in endoscopic settings, including the management of gastrointestinal bleeding and radiation-induced rectal bleeding [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Its ability to control capillary oozing and support tissue healing provides a plausible explanation for the clinical effects observed in this cohort. These findings informed our protocol of reassessment at three months, with consideration of repeat treatment even in the absence of recurrent haematuria.\u003c/p\u003e \u003cp\u003eAn additional advantage of this technique is its feasibility as an outpatient procedure under local anaesthesia, which is particularly relevant given the comorbidity burden in this patient population. Compared with HBOT, which requires multiple sessions over several weeks, this approach may offer a more accessible and less resource-intensive alternative.\u003c/p\u003e \u003cp\u003eThis study has important \u003cb\u003elimitations\u003c/b\u003e. It represents a small, single-arm pilot study including only ten patients, without a comparator group. While the observed clinical and endoscopic improvements are encouraging, these findings should be interpreted with caution. Further studies are required to assess the durability of response, determine the optimal number of treatment applications, and identify patient populations at risk of recurrence.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eIntravesical RADA16 appears to be a safe and feasible treatment for haemorrhagic radiation cystitis, deliverable via flexible cystoscopy under local anaesthesia. In this pilot cohort, treatment was associated with resolution of visible haematuria in the majority of patients, no unplanned hospital attendances, and no observed treatment-related adverse events. Larger controlled studies are needed to confirm efficacy, durability, and the optimal treatment regimen.\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eAuthorship formP.C.I.: Conceptualization, Methodology, Conducting a research and investigation process, specifically performing the experiments, or data/evidence collection, Validation, Formal analysis, Writing - Original DraftR.D.: Conducting a research and investigation process, specifically performing the experiments, or data/evidence collection, Writing - Review \u0026amp; EditingA.C.: Conducting a research and investigation process, specifically performing the experiments, or data/evidence collection, Writing - Review \u0026amp; EditingO.A.K.: Conducting a research and investigation process, specifically performing the experiments, or data/evidence collection, Writing - Review \u0026amp; EditingC.T.: Conducting a research and investigation process, specifically performing the experiments, or data/evidence collection, Writing - Review \u0026amp; EditingP.P.: Resources, Writing - Review \u0026amp; EditingC.R.: Conducting a research and investigation process, specifically performing the experiments, or data/evidence collection, Writing - Review \u0026amp; EditingF.R.: Management and coordination responsibility for the research activity planning and execution; Writing - Review \u0026amp; EditingT.D.: Management and coordination responsibility for the research activity planning and execution; Writing - Review \u0026amp; EditingL.S.: Conceptualization, Methodology, Validation, Formal analysis, Writing - Review \u0026amp; Editing\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eBrowne, C., Davis, N. F., Mac Craith, E., Lennon, G. M., Mulvin, D. W., Quinlan, D. M., Mc Vey, Gerard P., Galvin, D. J., A Narrative Review on the Pathophysiology and Management for Radiation Cystitis, Advances in Urology, 2015, 346812, 7 pages, 2015. https://doi.org/10.1155/2015/346812 \u003c/li\u003e\n\u003cli\u003eAndreyev J. Purastat therapy for bleeding radiation proctopathy. World J Gastrointest Endosc. 2026;18(1):112920. doi:10.4253/wjge.v18.i1.112920\u003c/li\u003e\n\u003cli\u003eStout TE, Borofsky M, Soubra A. A visual scale for improving communication when describing gross hematuria. Urology. 2021;148:32\u0026ndash;36. doi:10.1016/j.urology.2020.10.054\u003c/li\u003e\n\u003cli\u003eIlie PC, Darwazeh H, Hemsworth L, Smith L. Technique used for PuraStat\u0026reg; application in urinary bladder bleeding. aju [Internet]. 2023 Nov. 26 [cited 2026 Mar. 23];3:1. Available from: https://atenajournals.com/index.php/aju/article/view/82 [4]\u003c/li\u003e\n\u003cli\u003eDarwazeh H., Hemsworth L., Smith L., Ilie P. Cystoscopic application of PuraStat\u0026reg; in the treatment of radiation-induced haemorrhagic cystitis. Ann R Coll Surg Engl. 2024 doi: 10.1308/rcsann.2023.0034. Published online February 16. \u003c/li\u003e\n\u003cli\u003eGoucher G, Saad F, Lukka H, Kapoor A. Canadian Urological Association Best Practice Report: Diagnosis and management of radiation-induced haemorrhagic cystitis. Can Urol Assoc J. 2019;13(2):15-23. doi:10.5489/cuaj.5788.\u003c/li\u003e\n\u003cli\u003eWeiss JP, Mattei DM, Neville ED, et al. Primary treatment of radiation-induced haemorrhagic cystitis with hyperbaric oxygen: 10-year experience. J Urol. 1994;151:1514\u0026ndash;7. doi: 10.1016/S0022-5347(17)35289-8.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1. Patient inclusion and exclusion criteria\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"3\" cellpadding=\"0\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 51.1424%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eInclusion criteria\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48.8576%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eExclusion criteria\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 51.1424%;\"\u003e\n \u003cp\u003eAge \u0026ge;18 yr\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48.8576%;\"\u003e\n \u003cp\u003eAge \u0026lt;18 yr\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 51.1424%;\"\u003e\n \u003cp\u003ePelvic radiotherapy completed \u0026gt;6 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48.8576%;\"\u003e\n \u003cp\u003eInability to undergo complete cystoscopic evaluation\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 51.1424%;\"\u003e\n \u003cp\u003eEndoscopically confirmed radiation cystitis, characterised by friable telangiectasia, mucosal pallor, and oedema\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48.8576%;\"\u003e\n \u003cp\u003eOther untreated cause of haematuria\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 51.1424%;\"\u003e\n \u003cp\u003eClinically significant haematuria, defined as visible haematuria at least once weekly for \u0026ge;3 months, with or without anaemia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48.8576%;\"\u003e\n \u003cp\u003ePrevious PuraStat treatment for radiation cystitis\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 51.1424%;\"\u003e\n \u003cp\u003eNegative upper urinary tract evaluation (CT IVU)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48.8576%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 51.1424%;\"\u003e\n \u003cp\u003eCapacity to provide informed consent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48.8576%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2. Healthcare utilisation before and after treatment\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"3\" cellpadding=\"0\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eOutcome (per patient)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003ePre-treatment mean (SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003ePre-treatment median (IQR)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003ePost-treatment mean (SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eHospital attendances\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.4 (3.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.0 (1.0\u0026ndash;4.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eEmergency department visits\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.9 (3.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.5 (0.2\u0026ndash;4.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eInpatient days\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.1 (4.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.0 (0.8\u0026ndash;8.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eBlood transfusions (units)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.5 (0.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.0 (0.0\u0026ndash;0.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"4\"\u003e\n \u003cp\u003e\u003cem\u003eValues are presented per patient over the 3-month periods before and after treatment.\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"world-journal-of-urology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"wjur","sideBox":"Learn more about [World Journal of Urology](https://link.springer.com/journal/345)","snPcode":"345","submissionUrl":"https://submission.nature.com/new-submission/345/3","title":"World Journal of Urology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"RADA16, haemoragic cystitis, radiation cystitis, cystitis, haemoragic radiation cystitis, PuraStat, PuraBond","lastPublishedDoi":"10.21203/rs.3.rs-9284350/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9284350/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground and Objective\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHaemorrhagic radiation cystitis is a challenging complication of pelvic radiotherapy, with limited high-quality evidence to guide management and no established standard of care. We evaluated the real-world efficacy and safety of intravesical RADA16 (PuraStat) for the treatment of persistent severe haematuria secondary to radiation cystitis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis prospective observational study included patients with clinically significant haematuria following radiotherapy, treated with intravesical RADA16 across two NHS Trusts. The primary outcome was resolution of visible haematuria. Secondary outcomes included healthcare utilisation (hospital admissions, length of stay, emergency department attendances) and safety. Patients were followed for a minimum of 90 days.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eKey Findings and Limitations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTen patients (mean age 79.6 yr; 90% male) were included. Nine of ten patients had complete resolution of macroscopic haematuria during follow-up. One patient reported minimal, self-limiting haematuria occurring intermittently. No procedure-related adverse events were observed. Unplanned healthcare utilisation was reduced to zero in all patients following treatment. Follow-up cystoscopic assessment suggested improvement in bladder lesions. Limitations include the small sample size, single-arm design, and limited follow-up in some patients.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions and Clinical Implications\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIntravesical RADA16 appears to be a safe and feasible treatment for haemorrhagic radiation cystitis and was associated with resolution of haematuria in the majority of patients and elimination of unplanned hospital attendances. These findings support further evaluation in larger, controlled studies to confirm efficacy, durability, and optimal treatment protocols.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePatient Summary:\u003c/strong\u003e \u0026nbsp;We observed patients undergoing a new treatment for bleeding in the bladder that can occur after radiotherapy. Most patients stopped having visible bleeding after treatment, and none needed to return to hospital unexpectedly. This treatment may offer a simple and safe alternative to more invasive procedures, but larger studies are needed to confirm these results.\u003c/p\u003e","manuscriptTitle":"Cystoscopic RADA16 (PuraStat) for Persistent Severe Haematuria Secondary to Radiation Cystitis: A Prospective Two-centre Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-14 14:40:54","doi":"10.21203/rs.3.rs-9284350/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-05-06T12:31:16+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-20T13:56:40+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"279817022316307404021860767443557098427","date":"2026-04-20T11:30:58+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"242333747798982718927767431832047854019","date":"2026-04-20T11:19:35+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-18T14:35:53+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"270100499238601428659457110203276236488","date":"2026-04-18T14:25:29+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-07T14:35:00+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-04-02T16:14:37+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-04-02T13:40:35+00:00","index":"","fulltext":""},{"type":"submitted","content":"World Journal of Urology","date":"2026-03-31T21:06:27+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"world-journal-of-urology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"wjur","sideBox":"Learn more about [World Journal of Urology](https://link.springer.com/journal/345)","snPcode":"345","submissionUrl":"https://submission.nature.com/new-submission/345/3","title":"World Journal of Urology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"cdce9700-c0c3-48e5-80ed-d5b372931f2d","owner":[],"postedDate":"April 14th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Revision requested","date":"2026-05-06T12:31:16+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-05-06T12:41:30+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-14 14:40:54","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9284350","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9284350","identity":"rs-9284350","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}