Immunotherapy to reduce frequency of urinary tract infections in people with neurogenic bladder dysfunction; a pilot randomised, placebo-controlled trial

OBJECTIVE: To establish the feasibility of a randomized, placebo-controlled trial to investigate the effect of a specific immunotherapy bacterial lysate OM-89 (Uro-Vaxom(®)) in reducing the frequency of urinary tract infections in people with neurogenic bladder dysfunction. DESIGN: A parallel-group, double-blind, randomized, placebo-controlled trial. SETTING: Patients at home, recruited through out-patient contact, social media and patient support groups. SUBJECTS: People with a spinal cord injury, multiple sclerosis, transverse myelitis or cauda equina syndrome who had suffered three or more clinically diagnosed urinary tract infections treated with antibiotics over the preceding 12 months. INTERVENTIONS: All participants took one capsule of oral OM-89 immunotherapy (6 mg) or matching Placebo (randomisation ratio 1:1), once daily in the morning for 3 months. MAIN MEASURES: The primary outcome was occurrence of a symptomatic urinary tract infection treated with an antibiotic, assessed at 3 and 6 months. Feasibility measures included recruitment, retention and practical difficulties. RESULTS: Of 115 patients screened, 49 were recruited, one withdrew before randomization, and 23 were allocated to the control group receiving matching placebo. Six participants, all in the control group, discontinued the intervention; all participants provided full data at both follow-up times. Over 6 months, 18/25 active group patients had 55 infections, and 18/23 control group patients had 47 infections. Most research and clinical procedures were practical, and acceptable to participants. CONCLUSION: It is feasible to undertake a larger trial. We recommend broader inclusion criteria to increase eligibility and generalizability.