Pulmonary circulation
-
Pulmonary circulation · Dec 2016
Relevance of angiopoietin-2 and soluble P-selectin levels in patients with pulmonary arterial hypertension receiving combination therapy with oral treprostinil: a FREEDOM-C2 biomarker substudy.
Studies have suggested roles for angiopoietin-2 (Ang-2) and soluble P-selectin (sP-selectin) as biomarkers of disease severity and treatment response in pulmonary arterial hypertension (PAH), but additional data are required for validation. We evaluated these biomarkers using data from FREEDOM-C2, in which patients with PAH receiving stable monotherapy or combination therapy were randomized to receive additional treatment with oral treprostinil (up-titrated from 0.25 mg twice daily) or placebo for 16 weeks. Biomarker analysis was optional in FREEDOM-C2. ⋯ Baseline Ang-2 ≥12 ng/mL was associated with a reduced likelihood of having NT-proBNP <1,800 pg/mL at week 16 (multivariate odds ratio: 0.08; 95% confidence interval: 0.02-0.32). However, Ang-2 showed no significant association with the other assessed outcomes, and sP-selectin was not associated or correlated with any of the outcomes. These data suggest that Ang-2 and sP-selectin are not associated with response to oral treprostinil in patients already receiving stable PAH therapy.