Overactive bladder is a common condition that causes sudden urges to urinate, frequent urination, night-time urination, and sometimes leakage of urine. Many people with overactive bladder improve with lifestyle changes and medicines. However, some patients do not respond to these standard treatments and continue to suffer from bothersome symptoms. This study is designed to help patients who have not improved with available medical therapy.

Two treatments will be compared in this research. The first treatment uses platelet-rich plasma. Platelet-rich plasma is made from a patient's own blood and contains growth factors that may help repair the lining of the bladder and improve bladder function. The second treatment uses botulinum toxin. Botulinum toxin is a protein that can reduce unwanted bladder contractions and is already approved for use in patients with overactive bladder who did not respond to other treatments.

The purpose of this study is to evaluate whether platelet-rich plasma injection into the bladder wall is safe, effective, and durable when compared with botulinum toxin injection into the bladder muscle. We believe that platelet-rich plasma may improve bladder health by encouraging tissue repair and reducing inflammation, while botulinum toxin may reduce bladder overactivity by blocking chemical signals that cause muscle contractions.

This study will take place at Benha University Hospital in Egypt. About 48 adult participants with overactive bladder that has not improved after at least six months of medical therapy will be enrolled. Participants will be randomly assigned to one of two groups. One group will receive platelet-rich plasma injections into the bladder lining, and the other group will receive botulinum toxin injections into the bladder muscle. The procedures will be performed under anesthesia using a cystoscope, which is a thin instrument inserted into the bladder.

Participants will be followed for one year. At several time points during follow-up, they will complete bladder symptom questionnaires, keep a voiding diary, and undergo urodynamic studies to measure bladder capacity and function. Researchers will also monitor safety by recording any side effects, such as urinary tract infections or temporary difficulty emptying the bladder.

The main goal of this study is to determine whether platelet-rich plasma can reduce symptoms of overactive bladder as effectively as botulinum toxin, with fewer side effects and longer-lasting results. If successful, platelet-rich plasma could offer a new treatment option for patients who continue to struggle with overactive bladder despite standard medical therapy.

Inclusion Criteria:

• Age 18 years or older
• History of urgency, frequency, nocturia, with or without urge urinary incontinence, lasting for at least 6 months
• Failure of standard medical treatment (antimuscarinics, beta-3 adrenergic agonists, or other appropriate therapy) for at least 6 months
• Willing and able to complete bladder diaries, questionnaires, and urodynamic testing
• Provides informed consent

Exclusion Criteria:

• Pregnancy or lactation
• Previous intravesical biological therapy (e.g., platelet-rich plasma or botulinum toxin)
• Prior pelvic or bladder surgery that may affect bladder function
• Active urinary tract infection or sexually transmitted infection
• Vaginitis or chronic bacterial prostatitis
• Bladder or lower ureteral stones confirmed by imaging
• Bladder outlet obstruction on urodynamic study
• Bladder malignancy (mass on imaging or malignant cells on cytology)
• Use of indwelling urinary catheter
• Severe uncontrolled medical conditions (e.g., uncontrolled diabetes, advanced renal or hepatic impairment)
• Known hypersensitivity to botulinum toxin or contraindication to platelet-rich plasma preparation (e.g., coagulopathy, inability to discontinue anticoagulation safely)

De-identified individual participant data (IPD), including baseline characteristics, outcome measures, and safety data, will be made available to other qualified researchers for secondary analyses. Personal identifiers will be removed prior to sharing.

De-identified IPD and supporting documents will be available beginning 12 months after publication of the primary study results and will remain available for 5 years.

Data will be shared with researchers who provide a methodologically sound proposal that has been approved by the Research Ethics Committee of Benha Faculty of Medicine. Requests should be submitted to the principal investigator via institutional email. Data access will be provided through secure, password-protected electronic transfer.

The study is single-blinded. The outcome assessors who evaluate bladder diaries, questionnaires, and urodynamic tests will be blinded to treatment assignment. Participants and treating physicians will be aware of the intervention due to differences in preparation and administration.