While it remains uncertain whether DCA may be a good drug candidate for other primary mitochondrial diseases and will rescue lactic acidemia in all cases, this study demonstrates the apparent tolerability and preliminary efficacy of DCA across 3 evolutionarily distinct models of FBXL4 disease, namely C. elegans, zebrafish, and human fibroblasts. This evidence concerns the gene FBXL4 and inborn mitochondrial metabolism disorder.