A Phase 2 interventional study of Zinc Citrate Oral Capsule and Placebo in Overactive Bladder (OAB), sponsored by Endeavor Health. Recruiting at 1 site in United States. Open to female participants aged 21 Years to 100 Years. Per ClinicalTrials.gov, last updated 2026-07-02.
Sponsored by Endeavor Health · Phase 2, Interventional, and Treatment
This randomized, double-blind, placebo-controlled trial evaluates whether oral zinc plus phytase supplementation modifies clinical response to intradetrusor botulinum toxin injection in patients with overactive bladder. Participants will receive either zinc plus phytase supplementation or matching placebo for five days prior to intradetrusor botulinum toxin injection. Participants will be followed for six months after treatment to assess need for repeat botulinum toxin injection, urinary symptoms, and patient-reported outcomes related to overactive bladder.
BACKGROUND AND RATIONALE
Intradetrusor botulinum toxin injection is an established treatment for overactive bladder (OAB) refractory to behavioral and pharmacologic therapy. However, duration of therapeutic effect varies among patients, and repeat injections are frequently required. Botulinum toxin activity depends on enzymatic cleavage of synaptic proteins involved in acetylcholine release, and zinc is a cofactor that may influence toxin activity. Phytase may enhance zinc bioavailability by improving intestinal absorption.
This study evaluates whether short-course oral zinc plus phytase supplementation administered prior to intradetrusor botulinum toxin injection alters clinical response to treatment.
STUDY OBJECTIVES
Primary Objective:
To determine whether oral zinc plus phytase supplementation prior to intradetrusor botulinum toxin injection reduces the proportion of patients requiring repeat intradetrusor botulinum toxin treatment within 6 months.
Secondary Objectives:
STUDY DESIGN
This is a prospective, randomized, double-blind, placebo-controlled trial.
Participants with overactive bladder who are scheduled to undergo intradetrusor botulinum toxin injection as part of routine clinical care will be enrolled and randomized in a 1:1 ratio to receive either:
Study medication will be administered for five days prior to the scheduled intradetrusor botulinum toxin injection.
Participants, investigators, and study personnel involved in outcome assessment will remain blinded to treatment assignment.
STUDY PROCEDURES
Participants will undergo intradetrusor botulinum toxin injection according to standard clinical practice.
Following injection, participants will complete remote follow-up assessments every four weeks for six months. Assessments will include:
858 studies on the registry are indexed under Urinary Bladder, Overactive; 127 are open to participants now.
This study's planned enrollment of 72 is close to the median of 70 across 649 interventional studies indexed under Urinary Bladder, Overactive.
Browse Urinary Bladder, Overactive studies →Endeavor Health is the lead sponsor of 111 studies on the registry; 34 are open to participants now.
Of its 12 completed or terminated interventional studies of FDA-regulated products, 9 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Relapsed and refractory
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive zinc + phytase capsules for five days prior to the scheduled procedure date.
Drug: Zinc Citrate Oral Capsule
Participants will receive placebo capsules for five days prior to the scheduled procedure date.
Drug: Placebo
Zinc citrate 50mg combined with 7,500 phytase units in an oral capsule
Placebo oral capsule
Number of patients needing repeat intradetrusor botulinum toxin injection at 6 months
Number of patients who subjectively report a need for repeat intradetrusor botulinum toxin injection at 6 months following the index injection.
Time frame: 6 months
Urge urinary incontinence episodes assessed by 3-day Bladder Diaries
Mean number of urge urinary incontinence episodes based on 3-day bladder diaries
Time frame: 6 months
Urge urinary incontinence episodes assessed by PFDI-20 scores
Mean score on the Pelvic Floor Distress Inventory-20 (PFDI-20), a validated 20-item questionnaire assessing pelvic floor symptom distress. Total scores range from 0 to 300, with higher scores indicating greater symptom burden (worse outcome).
Time frame: 6 months
Adverse events
Any adverse events that occur after intervention is administered.
Time frame: 6 months
Plan to share: No — Individual participant data will not be shared.
No publications or documents are linked to this record.
Started Feb 2026 (actual). Primary completion is estimated for Dec 2026, 10 months after the start.
Of 22 phase 2 interventional studies under Urinary Bladder, Overactive, half reached primary completion within 17 months of starting (the median), counting those still running; a quarter within 11 and three quarters within 22. This study's planned 10 months is below that.
How these figures are worked out, and which studies are left out of them.
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Studies of the drug tested here: Zinc citrate