Low-Dose
Eplerenone (Inspra™) Reduces Proteinuria
in Type 2 Diabetics Without Increasing Serum Potassium
Eplerenone with enalapril reduces elevated potassium
levels.
Eplerenone
at a dose of 50 to 100 mg co-administered with
the ACE-inhibitor enalapril produces a similar
antiproteinuric effect as eplerenone at a dose
of 200 mg, while obviating the elevated potassium
levels seen with the higher dose, researchers
report.
The
finding was presented on May 15th at the 18th
Annual Scientific Meeting of the American Society
of Hypertension.
Eplerenone,
a selective aldosterone blocker recently approved
for the treatment of hypertension, was previously
shown to decrease proteinuria but also to increase
potassium levels at a dose of 200 mg daily. Murray
Epstein, MD of the University of Miami in Miami,
Florida, led a team of researchers in determining
whether lower doses of eplerenone would be as
effective while reducing this dangerous side effect.
The
multi-centre study included 268 patients with
Type 2 diabetes and albuminuria (with or without
a history of hypertension) being treated with
enalapril 20 mg.
Patients
were randomised to eplerenone 50 mg or 100 mg
daily, or placebo in addition to their enalapril
therapy. If their blood pressure was not controlled
at Week 4, amlodipine 2.5 mg was added, with the
dose doubled every two weeks, up to 10 mg, if
necessary.
Uncontrolled
hypertension was defined as levels greater than
130/80 mm Hg.. Patients were assessed at weeks
4, 8, and 12.
Patients
who received eplerenone and enalapril in combination
had a significantly reduced urinary albumin:creatinine
ratio compared with the enalapril monotherapy
group.
Incidence
of both sustained and severe potassium increases
were similar in the three treatment groups, and
were not clinically relevant. The incidence rates
were generally lower in patients receiving 50
mg or 100 mg eplerenone co-administered with enalapril
when compared with results from an earlier trial
that used eplerenone 200 mg with or without enalapril
10 mg in hypertensive patients with diabetes and
albuminuria (Epstein et al. Am J Hypertens 2002;15(Suppl
1):A24).
Other
adverse events (including gynaecomastia, mastodynia,
and impotence) were rare or absent and did not
differ among treatment groups.
This
study was sponsored by Pharmacia Corporation of
Peapack, New Jersey.
[Study
title: Characterization of the Antiproteinuric
Effect of Eplerenone in Patients with Type 2 Diabetes
Mellitus. Abstract P-181a]
