Improved survival with initial oral treprostinil in patients with pulmonary arterial hypertension

A recent study found that initial oral treprostinil improved survival while those who started treprostinil after a clinical worsening in the placebo group and tolerated the drug for up to 48 weeks, enjoyed substantial functional gains. This study was published in the journal, Advances in Therapy.

This trial was an open-label extension (OLE) of the FREEDOM-EV study which enrolled 470 patients who had experienced an investigator-assessed clinical worsening event. All OLE participants were kept on open-label oral treprostinil. Those participants who had previously been assigned to placebo or previously assigned treprostinil, continued with the dose titration. Assessments included measured N-terminal pro-brain natriuretic peptide (NT-proBNP) at week 48, functional class, and 6-min walk distance (6MWD) at 12-week intervals. Survival was studied using the Kaplan-Meier analysis while hazard ratio (HR) was measured using Cox proportional hazards.

At the end of the study, it was seen that initial administration of oral treprostinil reduced mortality. Those who were randomized to the placebo group and initiated on oral treprostinil after clinical worsening, showed a reduction in NT-proBNP of - 778 pg/mL, functional class shifts, and 6MWD improvements of + 84 m when compared to the OLE baseline. Modest trends were observed in those participants who were initially assigned placebo and did not show clinical worsening and also those participants who were on the study drug without clinical worsening but continued with the drug through week 48.

Based on the above results, it can be concluded that with initial treprostinil, improved survival in the entire data set may be observed while those participants in the placebo arm, who were kept on treprostinil after a clinical worsening and tolerated the drug at week 48, may exhibit substantial functional gains.