Compared to treatment with phosphodiesterase-5 inhibitor (PDE5i), either alone or in combination with endothelin receptor antagonist (ERA/PDE5i), initial therapy with an ERA in patients with systemic sclerosis/pulmonary arterial hypertension (SSc/PAH) was associated with a significantly worse time to clinical worsening (TTCW). This according to a study of 98 patients with SSc/PAH, including 24 treated with initial ERA, 59 with initial PDE5i, and 15 with initial ERA/PDE5i. Researchers found:

• TTCW was significantly worse in patients initially started on ERA vs PDE5i or ERA/PDE5i.

• 41.6% of patients in the ERA group died over a 3-year observation period, vs 6.8% in the PDE5i group, and 6.7% in the ERA/PDE5i group.

• Baseline factors independently associated with shorter TTCW were initial ERA (HR 2.63), lower diffusing capacity of the lungs for carbon monoxide (HR 0.69 per 10% change), and higher pulmonary vascular resistance (HR 1.10 per Wood unit change).

Citation: Lammi MR, Mathai SC, Saketkoo LA, et al. Association between initial oral therapy and outcomes in systemic sclerosis-related pulmonary arterial hypertension: Observations from PHAROS. [Published online ahead of print October 19, 2015]. Arthritis Rheumatol. doi: 10.1002/art.39478.