Recordati announced the U.S. FDA has approved Isturisa (osilodrostat) for the treatment of adults with Cushing’s disease for whom pituitary surgery is not an option or has not been curative. Recordati expects Istursia to become commercially available in the U.S. in the second or third quarter of 2020. Recordati acquired the global rights to osilodrostat in July of 2019.
The FDA approval of Isturisa was the Phase III LINC-3 clinical trial, which enrolled 137 adults, about 75% of who were women, with a mean age of 41 years. The majority either had pituitary surgery that didn’t cure the disease or who were not candidates for the surgery. In the 24-week, single-arm, open-label period, all patients received a starting dose of 2 milligrams of Isturisa twice a day that could be increased every two weeks up to 30 mg twice a day. At the end of the 24-week period, approximately half of patients had normal cortisol levels. At that time, 71 patients who did not need dose increases and tolerated the drug for at least 12 weeks joined an eight-week, double-blind, randomized withdrawal trial where they were given either Isturisa or a placebo. At the end of this withdrawal period, 86% of patients receiving the drug maintained cortisol levels with normal limits compared to 30% of placebo patients.
The most common side effects observed were adrenal insufficiency, headache, vomiting, nausea, fatigue and swelling caused by fluid retention. Some patients reported low cortisol levels, QTc prolongation, a heart rhythm condition, and increased levels of adrenal hormone precursor and androgens.
Isturisa was granted Orphan Drug Designation. The drug was approved for Cushing’s disease in January of 2020 by the European Commission.
About Isturisa (osilodrostat)
Isturisa is a cortisol synthesis inhibitor that works by preventing 11-betahydroxylase, an enzyme responsible for the final step of cortisol biosynthesis in the adrenal gland, from being created.
About Cushing’s Disease
Cushing’s disease is caused by a pituitary tumor that releases excess amounts of a hormone called adrenocorticotropin. This stimulates the adrenal gland to produce higher amounts of cortisol. It can result in high blood pressure, obesity, type 2 diabetes, blood clots in the legs and lungs, bone loss and fractures, a weakened immune system and depression. Patients are often noted to have thin arms and legs, a round red full face, increased fat around the neck, bruise easily, have purple stretch marks and weak muscles. Cushing’s disease affects women three times more than men and is most often diagnosed in adults between the ages of 30 and 50.