Journal article

Publication year: 2012

Pages: 768-774

Journal: Journal of the American College of Cardiology

Volume number: 60

Issue number: 8

ISSN: 0735-1097

eISSN: 1558-3597

Open access status: Bronze

DOI Link: https://doi.org/10.1016/j.jacc.2012.05.004

Publisher: Elsevier

Abstract: 

Objectives The aim of this study was to evaluate the long-term safety and durability of efficacy of tadalafil for pulmonary arterial hypertension.

Background Tadalafil is an oral phosphodiesterase-5 inhibitor approved for PAH treatment. In the multicenter, placebocontrolled, randomized, 16-week PHIRST (Pulmonary Arterial Hypertension and Response to Tadalafil) study, tadalafil 40 mg improved exercise capacity and delayed clinical worsening.

Methods Eligible patients from PHIRST received once-daily tadalafil 20 mg (T20 mg) or 40 mg (T40 mg) (n = 357) in the double-blind, 52-week, uncontrolled extension study (PHIRST-2); 293 patients completed PHIRST-2. Durability of efficacy was explored using the 6-min walk distance (6MWD) test. Clinical worsening and changes in World Health Organization functional class were evaluated.

Results The safety profile of tadalafil in PHIRST-2 was similar to that in PHIRST, with typical phosphodiesterase-5 inhibitor adverse events. The 6MWDs achieved in PHIRST for the subset of patients receiving T20 mg and T40 mg in both PHIRST and PHIRST-2 (406 +/- 67 m [n = 52] and 413 +/- 81 m [n = 59] at PHIRST-2 enrollment, respectively) were maintained at PHIRST-2 completion (415 +/- 80 m [n = 51] and 410 +/- 78 m [n = 59], respectively). Numerically fewer patients who were on T40 mg in PHIRST and PHIRST-2 experienced World Health Organization functional class deterioration (6% [n = 5]) compared with those randomized to T20 mg (9% [n = 7]) across both studies. Post hoc analyses showed that background bosentan use and higher 6MWD at PHIRST baseline were associated with fewer clinical worsening events.

Conclusions Long-term treatment with tadalafil was well tolerated in patients with pulmonary arterial hypertension. In patients receiving either T20 mg or T40 mg, the improvements in 6MWD demonstrated in the 16-week PHIRST study appeared sustained for up to 52 additional weeks of treatment in PHIRST-2. (Pulmonary Arterial Hypertension and Response to Tadalafil Study; NCT00549302) (J Am Coll Cardiol 2012;60:768-74) (C) 2012 by the American College of Cardiology Foundation

Harvard Citation style: Oudiz, R., Brundage, B., Galie, N., Ghofrani, H., Simonneau, G., Botros, F., et al. (2012) Tadalafil for the Treatment of Pulmonary Arterial Hypertension A Double-Blind 52-Week Uncontrolled Extension Study, Journal of the American College of Cardiology, 60(8), pp. 768-774. https://doi.org/10.1016/j.jacc.2012.05.004

APA Citation style: Oudiz, R., Brundage, B., Galie, N., Ghofrani, H., Simonneau, G., Botros, F., Chan, M., Beardsworth, A., & Barst, R. (2012). Tadalafil for the Treatment of Pulmonary Arterial Hypertension A Double-Blind 52-Week Uncontrolled Extension Study. Journal of the American College of Cardiology. 60(8), 768-774. https://doi.org/10.1016/j.jacc.2012.05.004