Provided is the benzothiazolone compound (R)-7-(2-(1-(4-butoxyphenyl)-2-methylpropan-2-ylamino)-1-hydroxyethyl)-5-hydroxybenzo[d]thiazol-2(3H)-one. The compound is a beta-2 adrenoreceptor agonist. The compound may be useful in the treatment of muscle wasting diseases such as muscular dystrophy, disuse-related atrophy, cachexia or sarcopenia.