Treprostinil for the treatment of pulmonary hypertension

A method of treating or preventing pulmonary hypertension in a subject, the method comprising:

• i) administering to said subject a first liquid composition comprising Treprostinil or a pharmaceutically acceptable salt or derivative thereof in a first concentration in aerosolized form for a first treatment period, and
• ii) administering to said subject a second liquid composition comprising Treprostinil or a pharmaceutically acceptable salt or derivative thereof in a second concentration in aerosolized form for a second treatment period following the first treatment period;
• wherein the second concentration of Treprostinil or a pharmaceutically acceptable salt or derivative thereof in the second liquid composition is higher than the first concentration of Treprostinil or a pharmaceutically acceptable salt or derivative thereof in the first liquid composition, and
• wherein the first and the second liquid compositions are aerosolized and administered to the subject using a soft mist inhaler.