Other potential ALS drugs targeting neuronal hyperactivity or excitotoxicity have been reported; memantine, a noncompetitive antagonist of N-methyl-D-aspartic acid (NMDA) receptors, has been shown to delay disease progression and prolong survival of SOD1 mutant ALS model mice [181] but has not demonstrated therapeutic benefits for ALS patients [182]. Here, SOD1 is linked to amyotrophic lateral sclerosis.