title: Comparison of vasopeptidase inhibitor, omapatrilat, and lisinopril on exercise tolerance and morbidity in patients with heart failure: IMPRESS randomised trial.
abstract: BACKGROUND
  We aimed to assess in patients with congestive heart failure whether dual inhibition of neutral endopeptidase and angiotensin-converting enzyme (ACE) with the vasopeptidase inhibitor omapatrilat is better than ACE inhibition alone with lisinopril on functional capacity and clinical outcome.
  
  
  METHODS
  We did a prospective, randomised, double-blind, parallel trial of 573 patients with New York Heart Association (NYHA) class II-IV congestive heart failure, left-ventricular ejection fraction of 40% or less, and receiving an ACE inhibitor. Patients were randomly assigned omapatrilat at a daily target dose of 40 mg (n=289) or lisinopril at a daily target dose of 20 mg (n=284) for 24 weeks. The primary endpoint was improvement in maximum exercise treadmill test (ETT) at week 12. Secondary endpoints included death and comorbid events indicative of worsening heart failure.
  
  
  RESULTS
  Week 12 ETT increased similarly in the omapatrilat and lisinopril groups (24 vs 31 s, p=0.45). The two drugs were fairly well tolerated, but there were fewer cardiovascular-system serious adverse events in the omapatrilat group than in the lisinopril group (20 [7%] vs 34 [12%], p=0.04). There was a suggestive trend in favour of omapatrilat on the combined endpoint of death or admission for worsening heart failure (p=0.052; hazard ratio 0.53 [95% CI 0.27-1.02]) and a significant benefit of omapatrilat in the composite of death, admission, or discontinuation of study treatment for worsening heart failure (p=0.035; 0.52 [0.28-0.96]). Omapatrilat improved NYHA class more than lisinopril in patients who had NYHA class III and IV (p=0.035), but not if patients with NYHA class II were included.
  
  
  CONCLUSIONS
  Our findings suggest that omapatrilat could have some advantages over lisinopril in the treatment of patients with congestive heart failure. Thus use of vasopeptidase inhibitors could constitute a potentially important treatment for further improving the prognosis and well being of patients with this disorder.
authors.affiliation: Division of Cardiology, Toronto General Hospital, University of Toronto, ON, Canada. jrouleau@torhosp.toronto.on.ca
authors.forename: J L
authors.initials: JL
authors.lastname: Rouleau
authors.forename: M A
authors.initials: MA
authors.lastname: Pfeffer
authors.forename: D J
authors.initials: DJ
authors.lastname: Stewart
authors.forename: D
authors.initials: D
authors.lastname: Isaac
authors.forename: F
authors.initials: F
authors.lastname: Sestier
authors.forename: E K
authors.initials: EK
authors.lastname: Kerut
authors.forename: C B
authors.initials: CB
authors.lastname: Porter
authors.forename: G
authors.initials: G
authors.lastname: Proulx
authors.forename: C
authors.initials: C
authors.lastname: Qian
authors.forename: A J
authors.initials: AJ
authors.lastname: Block
mesh_terms: D000804:Angiotensin II / Q000097:blood; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D009320:Atrial Natriuretic Factor / Q000097:blood; D004311:Double-Blind Method; D019332:Endothelin-1 / Q000097:blood; D017079:Exercise Tolerance / Q000187:drug effects*; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000401:mortality; D006801:Humans; D017706:Lisinopril / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D015260:Neprilysin / Q000037:antagonists & inhibitors*; D009638:Norepinephrine / Q000097:blood; D011446:Prospective Studies; D011725:Pyridines / Q000009:adverse effects / Q000627:therapeutic use*; D015635:Radionuclide Ventriculography; D012720:Severity of Illness Index; D015996:Survival Rate; D013841:Thiazepines / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D019332:Endothelin-1; D011725:Pyridines; D013841:Thiazepines; D000804:Angiotensin II; C106266:omapatrilat; D009320:Atrial Natriuretic Factor; D017706:Lisinopril; D015260:Neprilysin; D009638:Norepinephrine