Cushing’s syndrome drug Isturisa is approved in Korea

Gov’t reviews various dosage forms

MFDS completes safety and efficacy review of 1mg and 5mg doses

Various doses of ‘Isturisa’ (osilodrostat), a treatment for Cushing's syndrome, are expected to be approved in Korea soon.

 

According to industry sources on the 19th, the Ministry of Food and Drug Safety concluded the safety and efficacy review of Recordati Korea's Isturisa Film Coated Tab 1mg earlier this month and recently completed the safety and efficacy review of the 5mg dose as well.

 

Isturisa was previously approved by the US Food and Drug Administration (FDA) on March 6, 2020, the European Medicines Agency (EMA) on January 9, 2020, and Japan’s Pharmaceuticals and Medical Devices Agency (PMDA) on March 23, 2021.

 

Among the three dosage forms available – 1, 5, and 10 mg – the MFDS has completed a safety and efficacy review for the 1 and 5 mg doses.

 

Isturisa has been under review for approval in Korea since November last year after being designated as a Global Innovative products on Fast Track (GIFT) by the MFDS.

 

As the safety and efficacy review is the final step in the approval process, the drug’s approval is expected soon.

 

Isturisa inhibits CYP1181, an enzyme responsible for the final step of the cortisol pathway in the adrenal glands, and was designated as a GIFT product in April 2022, when Novartis' ‘Signifor Inj’ was withdrawn from the market and the only existing treatment option was eliminated.

 

The drug is indicated for the treatment of adult patients with Cushing’s disease for whom pituitary surgery is not an option or has not been curative and is taken orally twice a day.

 

Cushing's syndrome occurs when the body is exposed to excessive amounts of a hormone called glucocorticoids.

 

Glucocorticoids are produced by an endocrine organ called the adrenal glands, which are located on top of the kidneys and can occur when the adrenal glands produce more glucocorticoids than necessary, or when excessive amounts of glucocorticoids enter the body from the outside for various reasons.

 

Cushing's syndrome is characterized by a rounded, moon-shaped face and excessive subcutaneous fat deposits on the back of the neck and shoulders, and is most common in adults between the ages of 30 and 50.

 

It affects women three times more often than men.

 

It can cause health issues such as hypertension, obesity, type 2 diabetes, blood clots in the legs and feet, fractures, a weakened immune system, and depression, and can be diagnosed through a blood test and a 24-hour urine test.

 

Isturisa is also the first FDA-approved drug to work directly on cortisol overproduction by blocking an enzyme known as 11-beta-hydroxylase and preventing cortisol synthesis.

 

The safety and effectiveness of Isturisa were demonstrated in a clinical study involving 137 adult patients, where approximately half of the patients reached cortisol levels within normal limits at Week 24.

 

After Week 24, 71 patients who did not require further dose escalation and tolerated the drug participated in an 8-week double-blind, randomized withdrawal study in which withdrawals were treated with either Isturisa or placebo.

 

Results showed that 86% of the patients in the Isturisa arm maintained cortisol levels within normal limits.

 

On the other hand, only 30% of the placebo arm reached the same result.