(Reuters) – The U.S. Food and Drug Administration on Thursday approved Bayer AG’s long-acting treatment for hemophilia A, a rare genetic disorder in which blood does not clot easily, the company said in a statement.

The injection, marketed under the name Jivi https://www.prnewswire.com/news-releases/bayer-receives-fda-approval-for-jivi-new-hemophilia-a-treatment-with-step-wise-prophylaxis-dosing-regimen-300704579.html, has been approved for previously treated patients and adolescents aged 12 years or older and helps replace the reduced or missing protein, factor VIII, required to form blood clots.

Hemophilia A patients repeatedly experience bleeding in muscles, joints or other tissues, which can result in chronic joint damage over time, and is mainly seen in males.

The approval complements Bayer’s existing factor VIII treatments, Kogenate and Kovaltry, which had combined sales of 967 million euros in 2017.

But the class of drugs, which is already crowded by competitors seeking a share of the lucrative rare disease space, is facing a major threat from Roche’s new hemophilia drug Hemlibra.

Hemlibra has been approved in Europe for patients who have developed resistance, or inhibitors, to clotting factors and is due for a broader U.S. approval by October.

Most of the existing treatments are based on factor replacement therapies, notably from Shire as well as Sanofi, which earlier this year bought U.S. hemophilia specialist Bioverativ.

Moreover, gene therapy could also bring more radical changes to treating the bleeding disorder, with companies including Biomarin and Spark Therapeutics at work on treatments that have shown promise in clinical trials.

Jivi can be administered up to five days a week, allowing physicians to adjust the dosing regimen according to the patient’s needs, Bayer said.

(Reporting by Saumya Sibi Joseph in Bengaluru; Editing by Saumyadeb Chakrabarty and Shounak Dasgupta)