Pulmonary Arterial Hypertension Highlights

Pulmonary arterial hypertension (PAH) is a rare but progressive and often fatal cardiovascular disease. PAH is an excessive disorder with terrible diagnosis and shortened lifestyle expectancy. The epidemiology assessment by DelveInsight show that there were nearly 69,600 prevalent patient population of PAH in 2021 in the 7MM (the US, EU-5 countries (Germany, France, Italy, Spain, and the UK), and Japan).

Treatment landscape of PAH has historically concerned the sequential use of endothelin receptor agonists, prostacyclin therapies, and nitric oxide pathway modulators, which have wonderful mechanisms of movement main to pulmonary vasodilation, and development in exercising capacity, hemodynamic measures, and medical results for sufferers with PAH.

Over the last two decades the treatment modalities of PAH have expanded significantly. At the American Thoracic Society (ATS) International Conference 2022, Long-Term Efficacy of Oral Treprostinil (TRE) approved for the treatment of patients with PAH as an option for low- and intermediate-risk patients was discussed. Oral treprostinil improves exercise capacity in PAH patients not receiving other treatment. Oral treprostinil could provide a convenient, first-line prostacyclin treatment option for PAH patients not requiring more intensive therapy.

FREEDOM-EV, a global, event-driven trial which established that 3 times daily (TID) TRE delayed disease progression when added to oral monotherapy replaced parenteral treprostinil in carefully selected patients. Participants moved to an open-label extension study (OLE) after experiencing a clinical exacerbation event (CWE) during or at the completion of the parent study FREEDOM-EV (July 2018).

This open-label extension study collected data on participants who completed previously reported, placebo-controlled oral treprostinil studies. Eligible participants had completed the prospective parent studies and took increasing doses of oral treprostinil twice daily; some later transitioned to three times daily dosing. Investigators measured 6-minute walk distance at Month 12 as the sole efficacy measure but collected adverse events throughout the study. A single center measured pharmacokinetics in 13 subjects who changed dosing from twice daily to three times daily. Eight hundred and ninety-four participants enrolled and 71% completed one year of therapy, with a median total daily dose of 7 mg and a median 6-minute walk distance increase of 22 m (interquartile range, −14 to 67 m). Subjects achieving higher doses had larger increases in 6-minute walk distance; 42% of participants completed three years of therapy. Adverse events were typical for prostacyclin class therapy, but prostacyclin-type adverse events may have been better tolerated with three times daily dosing in 105 participants. In 13 participants transitioned to three times daily dosing with pharmacokinetic measurements before and after, trough drug levels were higher with three times daily dosing.

PBO participants who entered the OLE of FREEDOM-EV due to CWE had a significant increase in 6MWD, improved functional class, and reduced NT-pro-BNP 48 weeks after starting TRE. PBO participants who did not have CWE had modest numeric (but not significant) improvements in clinical measures during the first 48 weeks of the OLE study.

All these data strengthen the placebo-controlled FREEDOM-EV results and suggest that the TRE was effective even in a group of higher-risk PBO participants who had just had CWE.

According to the market assessment by DelveInsight, the PAH market is quite huge with a market size of approximately USD 4,800 million in 2021 for 7MM countries.

United Therapeutics expects to seek the approval of oral treprostinil in Europe upon completion of the FREEDOM-EV study. If approved, the drug will be able to gain some share from the market.

For a more detailed analysis of the PAH market, visit: Pulmonary Arterial Hypertension market