Macipah

Recommended Dosage: The recommended dosage of Macitentan is 10 mg once daily for oral administration. Doses higher than 10 mg once daily have not been studied in patients with PAH and are not recommended.

Pregnancy Testing in Females of Reproductive Potential: Obtain a pregnancy test in females of reproductive potential prior to Macitentan treatment, monthly during treatment and one month after stopping Macitentan. Initiate treatment with Macitentan in females of reproductive potential only after a negative pregnancy test.

Pediatric Use: The safety and efficacy of Macitentan in children have not been established.

Geriatric Use: Of the total number of subjects in the clinical study of Macitentan for PAH, 14% were 65 and over. No overall differences in safety or effectiveness were observed between these subjects and younger subjects.

The most common adverse reactions (more frequent than placebo by ≥3%) are anemia, nasopharyngitis/pharyngitis, bronchitis, headache, influenza, and urinary tract infection.

Endothelin (ET)-1 and its receptors (ETA and ETB ) mediate a variety of deleterious effects, such as vasoconstriction, fibrosis, proliferation, hypertrophy, and inflammation. In disease conditions such as PAH, the local ET system is upregulated and is involved in vascular hypertrophy and in organ damage. Macitentan is an endothelin receptor antagonist that inhibits the binding of ET-1 to both ETA and ETB receptors. Macitentan displays high affinity and sustained occupancy of the ET receptors in human pulmonary arterial smooth muscle cells. One of the metabolites of macitentan is also pharmacologically active at the ET receptors and is estimated to be about 20% as potent as the parent drug in vitro. The clinical impact of dual endothelin blockage is unknown.

Anti-hypertensive