A Phase 2 interventional study of Cidofovir and No Cidofovir in Transplantation Infection, sponsored by M.D. Anderson Cancer Center. Active, not recruiting at 1 site in United States. Open to participants aged 6 Years and older. Per ClinicalTrials.gov, last updated 2026-09-18.
Sponsored by M.D. Anderson Cancer Center · Phase 2, Interventional, and Treatment
The goal of this clinical research study is to learn if adding cidofovir to the standard of care can improve symptoms of hemorrhagic cystitis caused by the BK virus as compared to standard of care alone. The safety of cidofovir will also be studied.
The Study Drug:
Cidofovir is an anti-viral drug that is designed to treat or prevent infections caused by certain kinds of viruses.
Study Groups:
If you are found to be eligible to take part in this study, you will be randomly assigned (as in the flip of a coin) to 1 of 2 study groups and you will have an equal chance of being in either group:
Study Drug Administration:
If you are in Group 1, you will receive cidofovir by vein over about 1 hour 3 times per week. You will also receive standard of care, which may include oral pain drugs taken every 4 to 6 hours as needed, oral drugs for urinary urgency taken 2 times daily, and fluids given by vein to increase your urination rate.
If you are in Group 2, you will only receive the standard of care, as described above.
Study Visits:
Each week:
Every 2 weeks, you will complete the questionnaire about urinary problems.
Length of Study:
If you are in Group 1, you may continue taking the study drug for up to 4 weeks. Group 2 will take the standard of care for 4 weeks. If the doctor thinks it is needed Groups 1 and 2 can continue to receive standard of care after this study is over. If your symptoms get worse during the study and you are not receiving cidofovir, you may be eligible for further treatments, which may include cidofovir, after the study ends. You will no longer be able to take the study drug if the disease gets worse or intolerable side effects occur.
Your participation on the study will be over once you have completed the end-of-treatment visit and the follow-up visit.
End-of-Treatment Visit:
After you finish treatment:
Follow-up Visit:
Four (4) weeks after treatment ends:
This is an investigational study. Cidofovir is FDA approved and commercially available for the treatment of several viral infections. Its use in patients with the BK virus after a stem cell transplant is investigational.
Up to 40 patients will take part in this study. All will be enrolled at MD Anderson.
69 studies on the registry are indexed under Cystitis; 17 are open to participants now.
This study's enrollment of 27 is below the median of 112 across 50 interventional studies indexed under Cystitis.
Browse Cystitis studies →M.D. Anderson Cancer Center is the lead sponsor of 3,047 studies on the registry; 578 are open to participants now.
Of its 612 completed or terminated interventional studies of FDA-regulated products, 409 (67%) 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.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
Allogeneic and autologous transplant
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Creatinine clearance (CrCl)
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cidofovir 0.5 mg/kg IV 3 x week for 4 weeks
Drug: Cidofovir
Standard of Care: Pharmacologic management of pain, spasms, and urinary urgency with medications, hyper-hydration, or continuous bladder irrigation.
Other: No Cidofovir
0.5 mg/kg by vein (IV) 3 times a week for 4 weeks.
Also known as: Vistide
Standard of Care: Pharmacologic management of pain, spasms, and urinary urgency with medications, hyper-hydration, or continuous bladder irrigation.
Number of Patients with Microbiologic Response
Response defined as improvement in symptoms based on questionnaire, reduction or stability in grade of hemorrhagic cystitis, and level of virus must be a 1 log reduction from baseline when the BKV was first diagnosed.
Time frame: 8 weeks
Started Mar 2011 (actual). Primary completion is estimated for Mar 2028, 203 months after the start.
How these figures are worked out, and which studies are left out of them.
This study is active, not recruiting, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Cidofovir