Three principal pathways are implicated in the pathogenesis
of pulmonary arterial hypertension^*1

Pulmonary arterial hypertension (PAH) is a system out of balance

*Statements are based on observations reported from in vitro, animal, and human trials. The clinical significance is unknown.

Tracleer is indicated for the treatment of pulmonary arterial hypertension (PAH, WHO Group I) in patients with WHO Class II-IV symptoms, to improve exercise ability and decrease the rate of clinical worsening. Patients with WHO Class II symptoms showed reduction in the rate of clinical deterioration and a trend for improvement in walk distance. Physicians should consider whether these potential benefits are sufficient to offset liver injury in WHO Class II patients, which may preclude future use as their disease progresses.

Important safety information

Because of the associated risks, Tracleer may be prescribed only through the Tracleer Access Program.

Potential for serious liver injury (including, after prolonged treatment, rare cases of liver failure and unexplained hepatic cirrhosis in a setting of close monitoring)—Liver monitoring of all patients is essential prior to initiation of treatment and monthly thereafter.

High potential for major birth defects—Pregnancy must be excluded and prevented through the use of reliable forms of birth control; monthly pregnancy tests should be obtained.

Contraindicated for use with cyclosporine A and glyburide.

Please see full prescribing information including BOXED WARNING.

Review the role of endothelin in PAH

1. McLaughlin VV, McGoon MD. Pulmonary arterial hypertension. Circulation. 2006;114:1417-1431.
2. Tuder RM, Cool CD, Geraci MW, et al. Prostacyclin synthase expression is decreased in lungs from patients with severe pulmonary hypertension. Am J Respir Crit Care Med. 1999;159:1925-1932.
3. Barst RJ, Gibbs JSR, Ghofrani HA, et al. Updated evidence-based treatment algorithm in pulmonary arterial hypertension. J Am Coll Cardiol. 2009;54(suppl):S78-S84.
4. Badesch DB, McLaughlin VV, Delcroix M, et al. Prostanoid therapy for pulmonary arterial hypertension. J Am Coll Cardiol. 2004;43:56-61.
5. Tracleer (bosentan) full prescribing information. Actelion Pharmaceuticals US, Inc. August 2009.
6. Rich S, McLaughlin VV. Pulmonary hypertension. In: Libby P, Bonow RO, Mann DL, Zipes DE, eds. Braunwald's Heart Disease. 2 vols. 8th ed. Philadelphia, PA: Saunders Elsevier; 2008:1883-1914.
7. Miyauchi T, Masaki T. Pathophysiology of endothelin in the cardiovascular system. Annu Rev Physiol. 1999;61:391-415.
8. Giaid A, Yanagisawa M, Langleben D, et al. Expression of endothelin-1 in the lungs of patients with pulmonary hypertension. N Engl J Med. 1993;328:1732-1739.