FDA Clears Tretten for Coagulation Factor XIII Deficiency

Megan Brooks

December 23, 2013

The US Food and Drug Administration (FDA) today approved the first recombinant coagulation factor XIII A-subunit product (Tretten, Novo Nordisk) for the prevention of bleeding in adults and children with congenital factor XIII A-subunit deficiency.

Congenital factor XIII deficiency is a very rare genetic clotting disorder in which patients fail to make enough of the factor XIII protein, which is important for normal blood clotting. The incidence of factor XIII deficiency is estimated at 1 in 5 million births, according to the National Hemophilia Foundation.

"The approval of this product provides another therapeutic option for the prevention of bleeding in patients with Factor XIII A-subunit deficiency," Karen Midthun, MD, director of the FDA's Center for Biologics Evaluation and Research, said in an agency press release. "Without treatment, people with this rare condition are at risk for serious and life-threatening bleeding."

Factor XIII is composed of 2 subunits (A and B). Factor XIII deficiency is usually caused by a deficiency of the A-subunit.

Tretten is a recombinant analogue of the human factor XIII A-subunit that is produced in yeast cells and then further purified. It is a sterile freeze-dried powder to be reconstituted with diluent and injected intravenously. Tretten can be administered by a physician or be self-administered, the FDA said.

In studies involving 77 patients with congenital factor XIII A-subunit deficiency, Tretten was effective in preventing bleeding in 90% of patients when administered monthly, the FDA said.

Reported adverse effects included headache, pain in the extremities, and pain at injection site. No patient in the trial developed abnormal clots.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.