A steroid derivative compound of formula (I) in which: one of R and R is hydroxy and the other is hydrogen； or R and R together represent oxo； R is hydrogen or hydroxy； and the dotted lines represent single or double carbon-carbon bonds； and pharmaceutically acceptable salts and esters thereof are useful for the prevention or treatment of pain, for improving nerve regeneration after nerve injury or damage or disease, for the prevention or treatment of brain injury, damage or disease and for neuroprotection. Particularly useful compounds are 11-hydroxy-&Dgr；4-androstene-3,17-dione and 11-oxo-&Dgr；4-androstene-3,17-dione or their derivatives.
