EPI-743, an analog of coenzyme Q10, is an antioxidant that has been suggested to improve clinical outcomes in some cases of genetically confirmed LS in a small controlled study (Martinelli et al., 2012), while supplementation with B vitamins such as thiamine, a cofactor of PDH (pyruvate dehydrogenase) is being considered as a treatment option (Bar-Meir et al., 2001). This evidence concerns the gene PDP1 and Leigh syndrome.