0 1 6 ▁due ▁to ▁long - term ▁animal ▁to x icity . ▁ ▁Basic ▁research ▁has ▁also ▁identified ▁other ▁comp ounds ▁which ▁modified ▁SM N 2 ▁sp lic ing ▁in ▁vit ro , ▁like ▁sod ium ▁orth ovan ad ate ▁and ▁a clar ub ic in . ▁Mor ph ol ino - type ▁ant is ense ▁o lig on uc le ot ides , ▁with ▁the ▁same ▁cell ular ▁target ▁as ▁n us in ers en , ▁remain ▁a ▁subject ▁of ▁inten se ▁research , ▁including ▁at ▁the ▁University ▁College ▁London ▁and ▁at ▁the ▁University ▁of ▁Oxford . ▁ ▁SM N 2 ▁gene ▁activation ▁ ▁This ▁approach ▁a ims ▁at ▁increasing ▁expression ▁( activity ) ▁of ▁the ▁SM N 2 ▁gene , ▁thus ▁increasing ▁the ▁amount ▁of ▁full - length ▁SM N ▁protein ▁available . ▁▁ ▁Or al ▁sal but am ol ▁( al but er ol ), ▁a ▁popular ▁ast h ma ▁medicine , ▁showed ▁th era pe ut ic ▁potential ▁in ▁S MA ▁both ▁in ▁vit ro ▁and ▁in ▁three ▁small - scale ▁clin ical ▁tri als ▁involving ▁patients ▁with ▁S MA ▁types ▁ 2 ▁and ▁ 3 , ▁besides ▁offering ▁resp ir atory ▁benefits . ▁ ▁A ▁few ▁comp ounds ▁initially ▁showed ▁promise ▁but ▁failed ▁to ▁demonstrate ▁effic acy ▁in ▁clin ical ▁tri als : ▁▁ ▁But yr ates ▁( s od ium ▁but yr ate ▁and ▁sod ium ▁phen yl but yr ate ) ▁held ▁some ▁promise ▁in ▁in ▁vit ro ▁studies ▁but ▁a ▁clin ical ▁trial ▁in