Indirect treatment comparison between fixed-dose-combinations of
amlodipine/losartan and amlodipine/valsartan in blood pressure control.
Author(s): Lawrence Gould A(1), Unniachan S, Wu D.
Affiliation(s): Author information:
(1)Merck Research Laboratories, West Point, PA, USA.
Publication date & source: 2014, Int J Clin Pract. , 68(2):163-72
AIMS: This study compared blood pressure (BP) changes after 8 weeks of therapy
between a fixed-dose combination (FDC) of amlodipine/losartan and
amlodipine/valsartan using a network meta-analysis because no trials directly
compared amlodipine/losartan with other FDCs.
METHODS: A systematic search identified six randomised controlled trials
(amlodipine/losartan-3, amlodipine/valsartan-3) of FDCs and their component
monotherapies. Conventional fixed-effects methods were used to conduct the
comparisons. The primary and secondary effect measures were the changes in
sitting diastolic and systolic blood pressure (sitDBP, sitSBP) at 8 weeks
post-randomisation.
RESULTS: The estimated amlodipine/valsartan - amlodipine/losartan difference (95%
confidence interval) in sitDBP reduction was -1.27 mmHg, (-5.7, 2.2) for lower
dosages and -0.45 mmHg, (-3.7, 2.7) for higher dosages; for sitSBP, the values
were -3.74 mmHg, (-9.0, 2.9) for lower dosages and 0.2 mmHg, (-6.2, 6.0) for
higher dosages. The confidence of a greater reduction in BP (fixed difference =
0) on amlodipine/losartan 5/50 than on amlodipine/valsartan 5/80 was 77% for
sitDBP and 89% for sitSBP. The corresponding confidence for the higher doses was
61% for sitDBP and 48% for sitSBP. The findings support asserting with (fixed)
95% confidence that the BP reduction on amlodipine/valsartan 5/80 exceeds the
amlodipine/losartan 5/50 reduction by at most 1.6 mmHg for sitDBP, and at most
1.26 mmHg for sitSBP. The corresponding upper bounds for the higher dosages were
2.31 mmHg (sitDBP) and 5.38 mmHg (sitSBP).
CONCLUSIONS: The BP lowering effect with amlodipine/losartan and
amlodipine/valsartan was comparable. Potential superiority of the reductions
realised with amlodipine/valsartan relative to amlodipine/losartan, are unlikely
to be clinically material.
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