Opsumit

Opsumit can only be obtained with a prescription and treatment should be started and monitored by a doctor experienced in treating PAH. The medicine is available as 10 mg tablets and taken at a dose of one tablet every day.

For more information about using Opsumit, see the package leaflet or contact your doctor or pharmacist.

In PAH there is severe narrowing of the arteries of the lungs. Because more pressure is needed to force blood through the narrowed artery, this leads to high blood pressure in the lungs.

The active substance in Opsumit, macitentan, works by blocking endothelin receptors. These are part of a natural mechanism in the body that can cause arteries to narrow. In patients with PAH, this mechanism is overactive and, by blocking these receptors, macitentan helps widen the arteries in the lungs and thereby bring down the blood pressure.

In a main study involving 742 patients, Opsumit has been shown to reduce the risk of PAH-related illness, particularly the worsening of PAH symptoms. Patients in the study received either Opsumit or placebo (a dummy treatment) in addition to other PAH treatments for an average of 2 years. Around 37% of patients taking placebo had a worsening of their PAH symptoms compared with 24% of those who took Opsumit 10 mg.

The most common side effects with Opsumit (which may affect more than 1 in 10 people) include nasopharyngitis (inflammation of the nose and throat), anaemia (low red blood cell counts) and headache. Most side effects are mild to moderate in severity. For the full list of side effects reported with Opsumit, see the package leaflet.

In animal studies, Opsumit was shown to have an adverse effect on the development of embryos. Opsumit must therefore not be used in pregnant or breastfeeding women or in women who could become pregnant and who are not using reliable contraception. Women should also not become pregnant for one month after stopping treatment.

It must also not be used in patients with severe reduction in liver function or high levels of liver enzymes in the blood. For the full list of restrictions, see the package leaflet.

The European Medicines Agency decided that Opsumit’s benefits are greater than its risks and it can be authorised for use in the EU. Opsumit has been shown to be effective in reducing illness or deaths due to PAH and the side effects reported are similar to those reported with other medicines of its class and are considered to be manageable. However, as animal studies showed an adverse effect on the development of embryos, Opsumit must never be used in pregnant women or women who could become pregnant and are not using reliable contraception.

The company that markets Opsumit will send educational material to patients and healthcare professionals with information on the precautions to be taken when using Opsumit. Patients’ reminder cards will include a warning that the medicine must never be used in pregnant women and that women who could become pregnant must be using reliable contraception and should undergo monthly pregnancy tests.

Recommendations and precautions to be followed by healthcare professionals and patients for the safe and effective use of Opsumit have also been included in the summary of product characteristics and the package leaflet.

As for all medicines, data on the use of Opsumit are continuously monitored. Side effects reported with Opsumit are carefully evaluated and any necessary action taken to protect patients.

Opsumit received a marketing authorisation valid throughout the EU on 20 December 2013.