We treated the S63del mouse model of CMT1B with tadalafil, a PDE5 inhibitor with a longer half-life in vivo than sildenafil, or CYR119 [24], a novel brain-penetrant sGC stimulator, and evaluated proteostasis in the sciatic nerves, levels of cGMP, and morphological and functional indicators of neuropathy. The gene discussed is PDE5A; the disease is Charcot-Marie-Tooth disease type 1B.