PHILADELPHIA – Two clinical trials of the combination therapy of the neprilysin inhibitor sacubitril and the angiotensin II receptor blocker valsartan in patients with heart failure and reduced ejection fraction found that it lowered rates of all-cause death, compared to a renin-angiotensin-system inhibitor alone.
Furthermore, the treatment produced a more beneficial effect in women, who are more prone to heart failure and preserved ejection fraction (HFpEF), lead investigators reported at the American Heart Association scientific sessions.
A prespecified subgroup analysis of 4,796 patients in the PARAGON-HF trial found that the sacubitril/valsartan, or sac/val, combination had a significantly more beneficial risk reduction of first and recurrent hospitalizations for heart failure, as well as cardiovascular death, in women than men. A prespecified pooled analysis of 13,195 patients in the PARAGON-HF and the PARADIGM-HF trials also found women derived a greater benefit from the combination therapy than men, but also concluded that patients with heart failure and even mildly reduced ejection fraction had better outcomes. The results of both studies were published simultaneously with the presentations on Nov. 17 in Circulation (; ).
The findings underscore the effectiveness of sac/val combination in patients with HF and EF in the lower ranges, defined as 40% or less, commented discussant
, of the University of Glasgow presented the PARAGON-HF subgroup analysis. He said it initially focused on 12 subgroups, but that only two baseline variables showed a modified effect of sac/val: sex and left-ventricle ejection fraction (LVEF). The findings, he said, “stood up in a very robust, multivariable analysis.”
The women in the subgroup analysis were older, had higher baseline New York Heart Association class status, and worse quality of life as measured by Kansas City Cardiomyopathy Questionnaire clinical summary score. At baseline, women also had higher average LVEF (59% vs. 56%), lower N-terminal prohormone brain natriuretic peptide levels, and higher rates of renal dysfunction and chronic kidney disease, but lower incidence of a previous MI and coronary artery disease. Prestudy treatments were similar between the sexes.
In terms of the primary outcome – a composite of total hospitalizations for heart failure and cardiovascular death – “there was an apparent 27% relative risk reduction in women and no overall effect in men,” Dr. McMurray said of the treatment group. “The difference was driven completely by hospitalizations.” Rates of CV death were similar between the valsartan-only and sac/val groups in both men and women, he said.
In the analysis of LVEF, women in the treatment group seemed to cross over to a heightened risk of hospitalization and CV death at an LVEF in the 60%-65% range, Dr. McMurray said, whereas men made that cross over in the 50%-55% range. “It looks as though women might be getting more benefit from this treatment up to a higher EF than in men,” he said.
However, the differences between men and women did not hold up in the analysis of secondary outcomes. At 8 months, women in the sac/val group had a 0.6-point greater decline than did the valsartan-only patients in KCCQ-CSS score, whereas men on sac/val had a 2.8-point lesser decline than did those on valsartan only. Similar differences were seen between the treatment and valsartan-only groups within the sexes, with women showing a noticeable improvement surpassing the men.
Posttreatment hypotension rates in both sexes were higher in the sac/val groups, and the risk of renal dysfunction was a bit less in both treatment groups. Women in the treatment group had significantly higher rates of angioedema than did the valsartan-only group and men in either group.
“Compared to valsartan, it’s important to say that sacubitril/valsartan seemed to reduce the risk of heart failure and hospitalization more in women than men, but we didn’t find a similar differential for other endpoints,” Dr. McMurray said. “Therefore, we’re not sure this is a real effect or a chance finding. It’s very statistically robust, but it could still be a chance finding.”
A possible explanation could be than men may not be responding to sac/val, or that valsartan alone may be more effective in men than women, he said. “This possible effect modification of sac/val vs. valsartan by sex deserves further investigation,” he said.