Phage Therapy for Recurrent UTIs in Kidney Transplant Recipients

The overarching hypothesis is that phage therapy directed against E. coli in female KTR is safe and associated with a reduction in UTI event rate via a targeted impact on the gut and urinary microbiome. This is a Phase 1/ 2 randomized, placebo-controlled clinical trial. * A description of methods to be used to minimize bias Participants will be randomized to one of 2 arms - one active intervention phage therapy and the second is active intervention control arm (normal saline placebo). Participants will not be aware of study assignment and the medication delivered to them will look identical - clear 1mL solution in a plastic needless syringe. * The number of study groups/arms and study intervention duration: * Investigators plan to enroll participants that fulfill eligibility criteria until they reach their goal of 16 participants in each arm (total N= 32). This clinical trial will evaluate the effect of phage only (without concomitant antibiotics) compared to placebo for UTI prevention in asymptomatic female KTR with a history of rUTI. There are no rigorous, published trials testing this approach, nor are there new therapeutics for rUTI in KTR on-market at this time. Most IND cases or trials compare phage plus antibiotic which limits the ability to isolate the contribution from phage to treatment success. The proposed research will utilize a phase I/II pilot trial designed to assess the safety, tolerability, and feasibility of therapy, compare potential efficacy, and assess changes to microbiome profiles in the female participants who will receive either phage or placebo. As the participants will be treated when they are asymptomatic, no active control is needed and so Investigators will use normal saline placebo.