Treprostinil, a
prostacyclin analogue, is approved for the treatment of
pulmonary arterial hypertension (PAH) in adults. Transition from parenteral to oral
treprostinil has been successfully accomplished in adults with PAH but not in children. In this multicenter study, pediatric patients treated with parenteral (Cohort 1) or inhaled (Cohort 2)
treprostinil were transitioned to oral
treprostinil.
Prostacyclin-naïve individuals on background oral PAH
therapy received oral
treprostinil as add-on
therapy (Cohort 3). Successful transition was oral
treprostinil dose maintenance through week 24. Patients were monitored for adverse events (AEs), 6-min walk distance (6MWD), PAH symptoms, World Health Organization (WHO) Functional Class (FC), cardiac magnetic resonance imaging (cMRI), cardiopulmonary exercise testing (
CPET), and quality of life through 24 weeks. A total of 32 patients were enrolled in the study; 23 (72%) were girls (mean age = 12.2 years). All patients were on background oral PAH
therapy. Overall, patients (96.9%) maintained transition to oral
treprostinil; one patient (Cohort 1) transitioned to oral
treprostinil, then back to parenteral after experiencing
syncope and WHO FC change from II to III. Cohorts 1, 2, and 3 received a final mean oral
treprostinil dose of 5.6, 3.3, and 4.5 mg t.i.d., respectively. All cohorts had variable changes in 6MWD, cMRI, and
CPET. Overall, 12 serious AEs were reported. All patients had drug-related AEs including
headache (81%),
diarrhea (69%),
nausea (66%),
vomiting (66%), and
flushing (56%). Pediatric patients maintained transition to oral
treprostinil with preservation of exercise capacity and WHO FC.
Prostanoid-related AEs were most common and similar to those reported in adults.