Study Results
The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.
Basic Information
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COMPLETED
PHASE2
285 participants
INTERVENTIONAL
1997-03-31
2008-05-31
Brief Summary
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Detailed Description
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Specific Aim 1 To recruit 285 type 1 diabetic patients who do not have hypertension, diabetic nephropathy, or predictive levels of microalbuminuria into a 5-year study to determine the effect of inhibition of renin-angiotensin system activity with either losartan (angiotensin II blocker) or enalapril (converting enzyme inhibitor) on the development of diabetic renal disease. This aim has been accomplished and the study is entitled the Renin-Angiotension System Study (RASS).
Specific Aim 2 To obtain two percutaneous renal biopsies from each patient, the first, at entry into the study, and the second after five years of drug therapy with either losartan or enalapril.
Hypothesis Reduction of renin-angiotensin system activity will prevent or retard the development of histologic change in the kidney associated with diabetic nephropathy.
A secondary objective of this study is to evaluate retinal lesions in the RASS cohort of patients in order to determine the relationship of these findings to the histologic changes of DN and to examine the effects of RAS inhibition and/or systemic blood pressure (BP) on the development and progression of diabetic retinopathy. This ancillary study has the following aims:
Specific Aim To obtain baseline, 2.5 and 5 year retinal fundus photographs in the RASS patients.
Hypothesis Cross-sectional and longitudinal relationships of retinal and renal structural abnormalities will emerge which will improve the predictive value of renal functional tests. Reduction of rennin-angiotensin system activity will prevent or retard the development of diabetic retinal lesions
Conditions
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Keywords
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Study Design
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RANDOMIZED
PARALLEL
QUADRUPLE
Interventions
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enalapril
losartan
Eligibility Criteria
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Inclusion Criteria
* type 1 DM onset prior to 45; if onset was between ages 31-41, BMI \<26; onset 41-45, positive GAD or ICA required
* normal or increased GFR
* normal BP
* normoalbuminuric (\<20 ug/min on 2 of 3 time overnight urine collections)
Exclusion Criteria
* hypertension (\>85/135 mmHg)
* reduced GFR (\<90 ml/min/1.73m2)
* microalbuminuria
* solitary kidney or evidence of unilateral renal disease
* evidence of other important kidney disease by history, ultrasound or biopsy
* other chronic diseases or conditions such as cystic fibrosis, serious mental illness, severe mental retardation, etc.
* pregnancy or females planning pregnancy within 2 years were excluded due to the drugs being used
* compliance (pt not taking at least 85% of two week placebo were excluded)
16 Years
61 Years
ALL
Yes
Sponsors
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National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
NIH
Merck Sharp & Dohme LLC
INDUSTRY
Merck Frosst Canada Ltd.
INDUSTRY
Canadian Institutes of Health Research (CIHR)
OTHER_GOV
Michael Mauer, MD
INDIV
Principal Investigators
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S M Mauer, MD
Role: PRINCIPAL_INVESTIGATOR
University of Minnesota
Locations
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Mt Sinai Hospital, University of Toronto (Clinical Ctr)
Toronto, Ontario, Canada
Royal Victoria Hospital, McGill University (Data Center)
Montreal, Quebec, Canada
Montreal Childrens Hospital, McGill University (Clinical Ctr)
Montreal, Quebec, Canada
Countries
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References
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Mauer M, Zinman B, Gardiner R, Drummond KN, Suissa S, Donnelly SM, Strand TD, Kramer MS, Klein R, Sinaiko AR. ACE-I and ARBs in early diabetic nephropathy. J Renin Angiotensin Aldosterone Syst. 2002 Dec;3(4):262-9. doi: 10.3317/jraas.2002.048.
Limonte CP, Prince DK, Hoofnagle AN, Galecki A, Hirsch IB, Tian F, Waikar SS, Looker HC, Nelson RG, Doria A, Mauer M, Kestenbaum BR, de Boer IH. Associations of Biomarkers of Tubular Injury and Inflammation with Biopsy Features in Type 1 Diabetes. Clin J Am Soc Nephrol. 2024 Jan 1;19(1):44-55. doi: 10.2215/CJN.0000000000000333. Epub 2023 Oct 23.
Robiner WN, Strand TD, Mauer M; Renin Angiotensin System Study (RASS) Group. Adherence and renal biopsy feasibility in the Renin Angiotensin-System Study (RASS) primary prevention diabetes trial. Diabetes Res Clin Pract. 2013 Oct;102(1):25-34. doi: 10.1016/j.diabres.2013.06.004. Epub 2013 Sep 17.
Harindhanavudhi T, Mauer M, Klein R, Zinman B, Sinaiko A, Caramori ML; Renin Angiotensin System Study (RASS) group. Benefits of Renin-Angiotensin blockade on retinopathy in type 1 diabetes vary with glycemic control. Diabetes Care. 2011 Aug;34(8):1838-42. doi: 10.2337/dc11-0476. Epub 2011 Jun 29.
Klein R, Myers CE, Klein BE, Zinman B, Gardiner R, Suissa S, Sinaiko AR, Donnelly SM, Goodyer P, Strand T, Mauer M. Relationship of blood pressure to retinal vessel diameter in type 1 diabetes mellitus. Arch Ophthalmol. 2010 Feb;128(2):198-205. doi: 10.1001/archophthalmol.2009.391.
Mauer M, Zinman B, Gardiner R, Suissa S, Sinaiko A, Strand T, Drummond K, Donnelly S, Goodyer P, Gubler MC, Klein R. Renal and retinal effects of enalapril and losartan in type 1 diabetes. N Engl J Med. 2009 Jul 2;361(1):40-51. doi: 10.1056/NEJMoa0808400.
Other Identifiers
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9601M10705
Identifier Type: -
Identifier Source: org_study_id