The U.S. Food and Drug Administration has approved Fennec Pharmaceuticals Inc's intravenous therapy to prevent chemotherapy-induced hearing loss in children, according to the health regulator's website.

The approval, posted on the regulator's website late Tuesday, for Pedmark allows it to be used to reduce the risk of ototoxicity in children aged over one month who have undergone chemotherapy using the drug cisplatin.

Cisplatin is used in treating a range of cancers in children such as liver, bone and brain cancer, but can cause permanent hearing loss. Pedmark is now the only approved therapy to prevent cisplatin-induced hearing loss in the United States, with most patients opting for either cochlear implants or hearing aids. The company's shares closed nearly 16 per cent higher on Tuesday.

This was Fennec's third attempt to secure approval for the intravenous treatment. The FDA had twice declined to approve the therapy citing some deficiencies at the company's manufacturing facility.

According to Fennec, nearly 10,000 children in the U.S. and Europe receive chemotherapy with cisplatin or similar drugs each year, and the incidence of hearing loss depends on the duration and dosage of the therapy.