Positive results revealed from first prospective trial in heart failure due to Chagas disease

“HF caused by Chagas disease has unique clinical features with worse prognosis than other causes of HF despite the fact that patients are often younger and have fewer comorbidities,” explained Professor Renato Lopes from Duke University Medical Center, Durham, USA, Principal Investigator of the PARACHUTE-HF trial. “There have been no prospective randomised trials testing the effects of standard treatments in patients with Chagas disease and HF. In the general HF population, the angiotensin receptor–neprilysin inhibitor, sacubitril/valsartan improved HF outcomes vs. the angiotensin-converting enzyme inhibitor, enalapril,4 and we compared these two agents in the largest trial in patients with Chagas disease and HF conducted to date.”

PARACHUTE-HF was an academic-led, open-label, blinded-endpoint adjudication, randomised trial conducted at more than 80 sites in Brazil, Argentina, Mexico and Colombia. Eligibility criteria included a diagnosis of Chagas disease confirmed by at least two different serological tests positive for Trypanosoma cruzi infection, left ventricular ejection fraction (LVEF) ≤40%, New York Heart Association functional class II to IV symptoms and NT-proBNP ≥600 pg/ml or ≥400 pg/ml and hospitalisation for HF within the last 12 months. Participants were randomised 1:1 to either sacubitril/valsartan (50 or 100 mg twice daily titrated to a target of 200 mg twice daily) or enalapril (2.5 or 5 mg twice daily titrated to a target of 10 mg twice daily). The primary endpoint was a hierarchical composite outcome consisting of cardiovascular death, first hospitalisation for HF and the relative change from baseline to week 12 in NT-proBNP, analysed using a win ratio approach.5

In total, 922 patients were randomised. The mean age was 64 years, 42.0% were women, mean LVEF was 29.8% and 44.4% had had prior hospitalisation for HF.

Following pairwise comparisons, sacubitril/valsartan was associated with a 52% higher likelihood of a better primary outcome compared with enalapril (stratified unmatched win ratio 1.52; 95% confidence interval [CI] 1.28 to 1.82; p<0.001). Over a median of 25 months’ follow-up, rates were similar for sacubitril/valsartan vs. enalapril for cardiovascular death (hazard ratio [HR] 0.95; 95% CI 0.73 to 1.23) and first HF hospitalisation (HR 0.92; 95% CI 0.70 to 1.20). The significant difference in the primary outcome was predominantly driven by the percent change in NT-proBNP from baseline to 12 weeks: logarithmic median change from baseline was −30.6% in those assigned to sacubitril-valsartan and −5.5% in those assigned to enalapril (ratio of adjusted geometric mean change 0.68; 95% CI 0.62 to 0.75).

The safety profiles of the two agents were similar, with discontinuations due to adverse events occurring in 6.1% of patients with sacubitril/valsartan and 9.8% with enalapril.

Concluding, Professor Lopes said: “In patients with HF caused by Chagas disease, sacubitril/valsartan was superior to enalapril with respect to the primary outcome, predominantly driven by the 32% reduction in NT-proBNP levels at week 12. Our study provides the first randomised trial evidence to support a pharmacological treatment specifically in this high-risk population. PARACHUTE-HF shows that much-needed studies to better characterise chronic Chagas cardiomyopathy and to define the benefit/risk of new therapies in this condition are possible. In line with the global health spotlight of ESC Congress, the PARACHUTE-HF trial provides a successful model for international collaborations – in this field among cardiologists and infectious disease physicians − with the shared goal of evaluating the impact of new therapies on cardiovascular outcomes in patients with neglected diseases.”