The use of and outcomes with ambrisentan in clinical practice are different to those in clinical trials, reflecting different patient characteristics in the “real world”, say researchers.

Researchers analyzed data on 272 patients with pulmonary hypertension (PH) treated with ambrisentan in a UK hospital between March 2009 and June 2013.

They found that ambrisentan was given as monotherapy in just 33.5% of patients, and only 11.8% received it first-line. This contrasts with the original randomized controlled trials of ambrisentan (ARIES-1 and 2), in which all patients received the drug as a first-line monotherapy.

However, the researchers say that this usage “reflects commissioning and prescribing practice in the UK whereby initial therapy for PAH is [phosphodiesterase-5 inhibitors] with subsequent addition or switch to other therapies if initial response is suboptimal.”

“There are relatively few data describing the long-term use of ambrisentan in a less strictly defined population more reflective of the ‘real world’,” the team comments in Therapeutic Advances in Respiratory Disease.