More recently, Djouadi et al. (2005) demonstrated that addition of bezafibrate in the culture medium induced a dose-dependent (up to 3-fold) increase in palmitate oxidation capacities in fibroblasts from patients with the myopathic form of VLCAD deficiency, but not from severely affected patients. This biological improvement was related to drug-induced increases in VLCAD mRNA (+ 44 to + 150%), protein (1.5-2-fold) and residual enzyme activity (up to 7.7-fold) in cells from the patients. Bezafibrate also diminished the production of long-chain acyl-carnitines by 90% in cells harboring moderate VLCAD deficiency. The same group also investigated the response to bezafibrate as a function of genotype in 33 VLCAD-deficient fibroblasts representing 45 different mutations. Treatment with bezafibrate resulted in a marked increase in FAO capacities, often leading to restoration of normal values, for 21 genotypes that mainly correspond to patients with the myopathic phenotype (Gobin-Limballe et al., 2007).