Renal and Bone Outcome After Switching Tenofovir to Different Antiretroviral Strategies

Study Overview
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Brief Summary
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Renal outcome could be different after switching tenofovir to different antiretroviral strategies, in case of renal toxicity. Therefore, it is necessary to evaluate the importance of renal evolution in these patients, in terms of grade and time to renal improvement, according to the different options after interrupting tenofovir. The aim of this study was to explore the renal outcome after tenofovir according to new antiretroviral regimen.

Detailed Description
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Renal toxicity has become an important issue in a large number of HIV infected patients receiving a tenofovir-containing regimen. However, there are no data about the best antiretroviral regimen in patients switching tenofovir because of renal toxicity, in time, grade or persistence of renal improvement. Thus, patients with renal toxicity on tenofovir, defined as: a progressive decrease of at least 25% of estimated glomerular filtration rate (GFR, by chronic kidney disease-epi equation), or confirmed value of GFR below 60 ml/min in two successive determinations, or proximal tubular renal dysfunction, as indicated by the presence of at least 3 of the following parameters: proteinuria> 150 mg/g; excretion fractional of phosphorus in urine > 20%; glucosuria > 150 mg; or/and tubular proteinuria/albuminuria ratio above 0.4. who changed to the combination of abacavir plus a third drug, or to a nucleoside analogues-free antiretroviral combination (dual therapy, monotherapy) will be followed for 1 year to establish the time and grade of improvement (defined as the lack of above criteria).

Official Title
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A Prospective, Cohort Study of Renal and Bone Outcome After Changing Tenofovir in Patients With Renal Toxicity According to Antiretroviral Strategy

Conditions
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Renal Disease

Intervention / Treatment
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* Other: Tenofovir switch


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: HIV-infected patients Older than 18 years Receiving a Tenofovir-containing regimen, and with criteria of renal toxicity (see above) Switching the antiretroviral regimen Exclusion Criteria: Pregnancy Patients receiving prolonged therapy with other nephrotoxic drugs Patients not receiving or interrupting antiretroviral regimen

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Tenofovir switch<br>Patients switched tenofovir to different antiretroviral regimen according to physicians decision | Other: Tenofovir switch<br>* Patients switched tenofovir to different antiretroviral regimen according to physicians decision<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Renal outcome | Evolution of renal parameters after switching tenofovir according to antiretroviral drug or regimen used, in terms of GFR (glomerular filtration rate by Chronic Kidney Disease-epidemiological collaboration equation) improvement, increase in excretion fractional of phosphorus in urine, decrease in proteinuria, and in glycosuria. As control group, renal outcome will be evaluated in patients continuing TDF-based therapy | 48 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Antiviral efficacy | Number of patients without virological failure, defined as an HIV RNA level above 37 copies/ml, 48 weeks after the change of tenofovir | 48 weeks | 
| Bone mineral density (BMD) changes | Changes in BMD in the subgroup of patients with two successive BMD measurements, before and after TDF switch, according to baseline risk factors for BMD change (age, body mass index, hypovitaminosis D, secondary hyperparathyroidism), in comparison with patients continuing TDF | 48 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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renal toxicity, HIV, antiretroviral, outcome