Bosentan for treatment of inoperable chronic thromboembolic pulmonary hypertension: BENEFiT (Bosentan Effects in iNopErable Forms of chronIc Thromboembolic pulmonary hypertension), a randomized, placebo-controlled trial.
OBJECTIVE
Our goal was to investigate the effect of treatment with the oral dual endothelin receptor antagonist bosentan on the hemodynamics and exercise capacity of patients with chronic thromboembolic pulmonary hypertension (CTEPH).


BACKGROUND
CTEPH is characterized by vascular obstruction and remodeling, leading to increased pulmonary vascular resistance (PVR). Although pulmonary endarterectomy (PEA) is potentially curative, medical therapy is needed in patients with inoperable disease or persistent/recurrent pulmonary hypertension after PEA.


METHODS
The BENEFiT (Bosentan Effects in iNopErable Forms of chronIc Thromboembolic pulmonary hypertension) study was a double-blind, randomized, placebo-controlled study in CTEPH including patients with either inoperable CTEPH or persistent/recurrent pulmonary hypertension after PEA (>6 months after PEA). Independent coprimary end points were change in PVR as a percentage of baseline and change from baseline in 6-min walk distance after 16 weeks of treatment with bosentan or placebo. Secondary end points included change from baseline in World Health Organization functional class and other hemodynamic parameters.


RESULTS
One hundred fifty-seven patients were enrolled and randomized: 80 to placebo, 77 to bosentan. A statistically significant treatment effect (TE) of bosentan over placebo on PVR was demonstrated: -24.1% of baseline (95% confidence interval [CI]: -31.5% to -16.0%; p < 0.0001). Total pulmonary resistance (TE: -193 dynxsxcm(-5); 95% CI: -283 to -104 dyn.s.cm(-5); p < 0.0001) and cardiac index (TE: 0.3 lxmin(-1)xm(-2); 95% CI: 0.14 to 0.46 lxmin(-1)xm(-2); p = 0.0007) improved. Mean TE on 6-min walk distance was +2.2 m (95% CI: -22.5 to 26.8 m; p = 0.5449). Bosentan treatment was well tolerated.


CONCLUSIONS
This study demonstrated a positive TE of bosentan on hemodynamics in this patient population. No improvement was observed in exercise capacity. Further trials are needed to define the role of medical therapy in patients with CTEPH (Bosentan Effects in Inoperable Forms of Chronic Thromboembolic Pulmonary Hypertension; NCT00313222).
Jaïs
Xavier
X
Antoine Béclère Hospital, Clamart, France.
D'Armini
Andrea M
AM
Jansa
Pavel
P
Torbicki
Adam
A
Delcroix
Marion
M
Ghofrani
Hossein A
HA
Hoeper
Marius M
MM
Lang
Irene M
IM
Mayer
Eckhard
E
Pepke-Zaba
Joanna
J
Perchenet
Loïc
L
Morganti
Adele
A
Simonneau
Gérald
G
Rubin
Lewis J
LJ
D000959:Antihypertensive Agents / Q000627:therapeutic use*; D000077300:Bosentan; D002908:Chronic Disease; D018450:Disease Progression; D004311:Double-Blind Method; D004691:Endarterectomy; D065128:Endothelin Receptor Antagonists; D017079:Exercise Tolerance / Q000187:drug effects; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D006976:Hypertension, Pulmonary / Q000188:drug therapy* / Q000209:etiology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012720:Severity of Illness Index; D013449:Sulfonamides / Q000627:therapeutic use*; D013923:Thromboembolism / Q000150:complications*
D000959:Antihypertensive Agents; D065128:Endothelin Receptor Antagonists; D013449:Sulfonamides; D000077300:Bosentan