FDA Approves Kygevvi as First Treatment for Thymidine Kinase 2 Deficiency, on Evidence From 78 Patients
On November 3, the U.S. Food and Drug Administration (FDA) approved Kygevvi (doxecitine and doxribtimine) powder for oral solution for the treatment of thymidine kinase 2 deficiency (TK2d) in adults and pediatric patients with an age of symptom onset on or before 12 years. The sponsor is UCB, Inc. Kygevvi is the first and only approved treatment for TK2d and previously received FDA Orphan Drug, Breakthrough Therapy, Priority Review and Rare Pediatric Disease designations.
TK2d is an ultra-rare, autosomal recessive mitochondrial DNA depletion syndrome caused by biallelic pathogenic variants in the TK2 gene. Kygevvi, a combination of two pyrimidine nucleosides, works as a substrate enhancement, or molecular bypass, therapy.
The FDA based its approval on combined evidence from an ongoing Phase 2 trial (Trial 1, NCT03845712, in 47 adult and pediatric patients), two retrospective chart review studies (NCT03701568 and NCT05017818), and an expanded access program, covering 66 pediatric and 12 adult patients with genetically confirmed TK2d and symptom onset at or before 12 years of age. UCB expects Kygevvi to be commercially available in the United States in the first quarter of 2026.
Source: U.S. Food and Drug Administration
Published by GSM · USA (original Chinese edition)
Photo: 图中是美国食品药品管理局（FDA）总部51号楼主入口。Wikimedia Commons / U.S. Food and Drug Administration, Public domain
