Isturisa, Oral Treatment for Cushing’s Syndrome, Available in Germany

Isturisa (osilodrostat) is now available in Germany to treat adults with endogenous Cushing’s syndrome.

The announcement by Recordati Rare Diseases, which acquired rights to Isturisa from its original developer Novartis, follows the medication recently becoming available in the U.S. and in France.

Isturisa was approved by the European Commission to treat endogenous Cushing’s syndrome in January, and was approved by the U.S. Food and Drug Administration as a treatment for Cushing’s disease in March.

Endogenous Cushing’s syndrome is caused by the overproduction of the hormone cortisol by the adrenal glands. Isturisa is an oral medicine that works by blocking the activity of 11-beta-hydroxylase, an enzyme that is involved in the production of cortisol. By blocking this enzyme, Isturisa can prevent excessive cortisol production, thereby alleviating the symptoms of Cushing’s syndrome.

Isturisa’s approval was based on results from the LINC-3 Phase 3 clinical trial (NCT02180217), which enrolled 137 people with Cushing’s disease. All were initially given Isturisa, with dose adjustments based on efficacy and tolerability. Then, the 71 participants who achieved normal cortisol levels (as measured in the urine) were randomly assigned to either a placebo or to continue on Isturisa for eight weeks.

After this eight-week period, significantly more patients who stayed on Isturisa continued to have normal urine cortisol levels, compared with those who were switched to placebo (86% vs 29%). In addition to cortisol control, trial results also indicated that Isturisa eased symptoms, lessened comorbidity, and improved quality of life.

The most common side effects of Isturisa were fatigue, nausea, headache, edema (swelling), and adrenal insufficiency (inadequate production of hormones by the adrenal glands).

“Data from the LINC-3 study underline the efficacy and safety of Isturisa in a prospective setting and represent a significant advance in the treatment of patients with Cushing’s disease, a serious and potentially life-threatening rare disease,” Rosario Pivonello, MD, PhD, a professor at the Federico II University of Naples and investigator on the LINC-3 clinical trial, said in a press release.

“I would like to thank all patients who participated in the LINC-3 study and their families who helped make this new and welcome therapy option available for this underserved patient population.”

In addition to Isturisa, Recordati Rare Diseases also markets Signifor (pasireotide) across Europe and in the U.S. for people with Cushing’s disease for whom surgery has failed or is not an option.