WASHINGTON, April 17 (Xinhua) -- The U.S. Food and Drug Administration (FDA) approved Tuesday the first drug to treat a rare, inherited form of rickets.
The Crysvita (burosumab) can be used to treat adults and children ages one year and older with x-linked hypophosphatemia (XLH) which causes low levels of phosphorus in the blood, according to the FDA.
The rare disease leads to impaired bone growth and development in children and adolescents, and problems with bone mineralization throughout a patient's life.
"XLH differs from other forms of rickets in that vitamin D therapy is not effective," said Julie Beitz, director of the Office of Drug Evaluation III in the FDA's Center for Drug Evaluation and Research.
"This is the first FDA-approved medication for the treatment of XLH and a real breakthrough for those living with this serious disease," Beitz said.
XLH is a serious disease affecting nearly 3,000 children and 12,000 adults in the United States, according to the FDA.
The safety and efficacy of Crysvita have been studied in four clinical trials. In the placebo-controlled trial, 94 percent of adults receiving Crysvita once a month achieved normal phosphorus levels compared to 8 percent of those receiving placebo.
In children, 94 to 100 percent of patients treated with Crysvita every two weeks achieved normal phosphorus levels.
In both children and adults, X-ray findings associated with XLH improved with Crysvita therapy.
