Antibiotics for Kidney Transplant Recipients

Launched by UNIVERSITY OF CALIFORNIA, SAN FRANCISCO · Jul 29, 2025

Keywords

ClinConnect Summary

This clinical trial is studying whether continuing a common antibiotic called trimethoprim-sulfamethoxazole (TMP-SMX) for an extra six months can help prevent urinary tract infections (UTIs) in children and young adults who have recently had a kidney transplant. Usually, patients take this antibiotic for six months after their transplant, but this study wants to see if taking it for a full year reduces the number of UTIs and what side effects might occur. To find out, researchers will compare the antibiotic to a placebo—a pill that looks the same but doesn’t contain medicine.

Young people between the ages of 13 and 29 who had a kidney transplant at UCSF within the last six months and have already taken TMP-SMX without serious problems are eligible. Participants also need to be considered “high risk” for UTIs because of factors like having certain kidney or urinary tract conditions, diabetes, past UTIs, or complications after transplant. If accepted, participants will take either TMP-SMX or the placebo every day for six months, attend three check-in visits, complete short monthly online surveys about symptoms or side effects, and share their routine blood and urine test results with the study team. This study is not yet recruiting but aims to learn if longer antibiotic use is safe and helpful in preventing infections after kidney transplant.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • Age 13-29 years at time of recruitment
• • Kidney transplant performed at a UCSF facility within the last 6 months
• • Most recent glomerular filtration rate (GFR) \>30 mL/min/1.73 m2
• • Tolerated initial 6 months of post-transplant TMP-SMX (defined as no intentional periods of TMP-SMX cessation in first 6 months after transplant due to hyperkalemia, allergic reaction, or unexpected/excessive neutropenia)
• • Considered "high risk for UTI" after kidney transplant, as defined by one or more of the following: (1) Congenital anomaly of kidney/urinary tract as kidney failure etiology, (2) Diabetes mellitus (diagnosed either prior to or new-onset after transplant), (3) History of recurrent UTIs as diagnosed by a provider prior to transplant, (4) Occurrence of any UTI in first 6 months after transplant, (5) Delayed graft function (defined as need for dialysis within 7 days of transplant)
• • Patient and/or caregiver ability to read and understand English or Spanish
• Exclusion Criteria:
• • History of intolerance or allergy to trimethoprim (TMP) and/or sulfamethoxazole (SMX)
• • History of UTI due to a TMP-SMX-resistant organism in the first 6 months after transplant
• • Moderate or severe neutropenia (absolute neutrophil count \<1,000 cells/μL) on most recent bloodwork available at the time of recruitment
• • Uncontrolled hyperkalemia (serum potassium ≥5.0 mEq/L) on most recent bloodwork available at the time of recruitment
• • Provider-determined/documented need for either continuation or discontinuation of TMP-SMX prophylaxis that would preclude the patient's randomization
• • Current pregnancy
• • Incarcerated individuals/prisoners
• • Inability to provide informed consent or assent, and no legally authorized representative available