In a 2009 open pilot clinical trial, we proposed that bezafibrate, a widely prescribed hypolipidemic drug, could be effective for treating carnitine palmityl transferase 2 (CPT2) deficiency (Bonnefont et al. 2009). This defect of mitochondrial fatty acid oxidation (FAO) belongs to a group of rare diseases without pharmacological treatment that carries significant morbidity in children and adults. As with other rare disorders, few clinical trials are conducted for FAO, and maintaining research momentum is critical in developing solutions for unmet treatment needs. Consistent with pharmacological studies in cells from patients with the muscular form of CPT2 deficiency, we demonstrated a stimulation of muscle FAO after bezafibrate treatment for 6 months, accompanied with improvements in patients’ clinical condition (Bonnefont et al. 2009, 2010).