The U.S. Food and Drug Administration has approved Korlym (mifepristone) to control hyperglycemia (high blood sugar levels) in adults with endogenous Cushing's syndrome, who have type 2 diabetes or glucose intolerance, who remained unresponsive to previous surgery or are not eligible candidates for surgery. Pregnant women should never take Korlym (contraindicated).
Until the FDA approved Korlym for the treatment of endogenous Cushing's syndrome, there were no approved medications to treat the disorder.
Endogenous Cushing's syndrome is a debilitating and rare multisystem disorder which affects individuals mainly between the ages of 25 and 40. The disorder is caused by excess levels of the hormone cortisol. Cortisol is a steroid hormone produced by the adrenal glands that increases blood sugar levels. The FDA granted Korlym with an orphan drug designation in 2007. Approximately 5,000 patients will be eligible for Korlym therapy.
Korlym works by preventing cortisol attaching to its receptor. Although the treatment does not lower the production of cortisol, it does lower the effects of excess cortisol, such as increased blood sugar levels.
In a human trial involving 50 patients with endogenous Cushing's syndrome, researchers assessed the safety and efficacy of Korlym. An independent open-label extension of this study is currently underway.
Further evidence backing the FDA's approval of Korlym included published scientific literature, numerous safety pharmacology investigations, and drug-drug interaction studies. During Korlym treatment, participants experienced considerable improvement in blood sugar control, and some participants had reductions in their insulin needs.
The researchers found that the most prevalent adverse effects experienced by participants receiving Korlym for endogenous Cushing's syndrome were vomiting, dizziness, headache, reduced appetite, arthralgia, swelling of the extremities, fatigue, and nausea.
Additional adverse effects include vaginal bleeding, low potassium levels, and a potential for heart conduction abnormalities. As certain medications used in conjunction with Korlym may increase its drug levels, it is vital that health care professionals be aware of the possibility of drug-drug interactions and either avoid using certain medications with Korlym or adjust dosing.
Even though it is very rare for women with Cushing's syndrome to fall pregnant, due to the disorder's suppressive effect on excess cortisol on female reproductive function, pregnant women should never take Korlym. The medication will carry a Boxed Warning advising patients and health care professionals that Korlym will terminate pregnancy.
According to the FDA, a Risk Evaluation and Mitigation Strategy (REMS) to make sure that the benefits of Korlym outweigh the risks for individuals with endogenous Cushing's syndrome is not necessary.
The FDA took into account several factors when making this conclusion, including:
- In the U.S., the number of health care professionals who would potentially prescribe the medication is extremely small and highly specialized. They are familiar with the risks of the drug in individuals with endogenous Cushing's syndrome and frequently monitor patient status.
- As no other medications are approved to treat the disorder, very ill individuals would suffer if impediments to access were imposed.
- Only an estimated, 5,000 patients with the disorder are eligible for treatment.
- The risks of Korlym therapy in those prescribed with the drug will be controlled by physician and patient labeling. Furthermore, the risks linked to Korlym will be highlighted in the patients' medication guide.
Written by Grace Rattue