The first approved medicine for the rare heart and lung disease chronic thromboembolic pulmonary hypertension (CTEPH) is now available in the UK following the launch of Bayer's Adempas (riociguat) this week.

The drug, a soluble guanylate cyclase (sGC) stimulator, can be prescribed for adult patients with WHO Functional Class II to III with inoperable or persistent disease to improve exercise capacity.

CTEPH, which affects around 1,300 people in the UK, is a rare form of pulmonary hypertension, characterised by high blood pressure in the pulmonary arteries causing breathlessness, fatigue and hindering everyday activities.

Surgery remains the first line of addressing the condition, but up to 40% of patients are not eligible and 10%-35% have disease that persists after the operation. These patients urgently need effective new treatments to manage their disease.

"CTEPH can have a devastating impact on the lives of patients who, on a daily basis, struggle to breathe and experience dizziness and fainting, all which can be very frightening. As such riociguat is the start of a new era in the management of CTEPH,” sati Iain Armstrong, Consultant Nurse at the Royal Hallamshire Hospital, commenting not the launch.

According to Bayer, a pivotal Phase III trial (CHEST-1) showed Adempas to be the first ever drug to provide statistically significant clinical efficacy in patients with inoperable CTEPH or recurrent or persistent disease after surgery. 

Data showed that it significantly improved patients’ exercise capacity, with patients taking the drug able to walk an average of 46 additional metres in the six minute walk test after 16 weeks compared with placebo.

Riociguat is also indicated to treat patients with pulmonary arterial hypertension, a progressive and life-threatening disease in which the blood pressure in the pulmonary arteries is significantly increased due to vasoconstriction and which can lead to heart failure and death.