FDA approves treatment for pediatric patients with congenital athymia

Oct. 12, 2021

The U.S. Food and Drug Administration (FDA) approved Rethymic for the treatment of pediatric patients with congenital athymia, a rare immune disorder. Rethymic is the first thymus tissue product approved in the U.S.

“Today’s action marks the first FDA approval of a therapy to treat this very rare and devastating disease in children,” said Peter Marks, MD, PhD, Director of the FDA’s Center for Biologics Evaluation and Research.

Congenital athymia is a rare immune disorder in which a child is born without a thymus — an organ that plays a critical role in helping the body learn to fight infections. Children impacted by this disease typically die within the first two years of life and may have repeated, often life-threatening infections because they lack adequate working T cells (a kind of infection-fighting white blood cell).

Rethymic is composed of human allogeneic (donor-derived) thymus tissue that is processed and cultured, and then implanted into patients to help reconstitute immunity (improve immune function) in patients who are athymic. Dosing is patient customized, determined by the surface area of the Rethymic slices and the body surface area of the patient. Rethymic is not indicated for the treatment of patients with severe combined immunodeficiency (SCID).

It takes six months or longer to reconstitute the immune function in treated patients; therefore, it is important that until immune reconstitution occurs patients continue to take strict precautions to prevent infections and healthcare providers should treat accordingly.

The FDA granted approval of Rethymic to Enzyvant Therapeutics.

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