The European Commission has approved Novartis' drug Signifor to treat a rare hormonal disorder, the Swiss drugmaker said on Monday.

The drug, used to treat adults with acromegaly for whom surgery is not an option, was approved after two late-stage studies showed the drug allowed for greater disease control than existing therapies, Novartis said.

Acromegaly is caused by a benign tumor in the pituitary gland that secretes excess growth hormone, and can lead to the enlargement of body parts, including the hands, feet and facial features.

An estimated one to two people per 10,000 are affected with the disease in the European Union, according to Novartis.