NE-100 is a potent antagonist of sigma-1 (σ1) receptor. It inhibits binding of (+)-pentazocine binding to sigma-1 binding sites with an IC₅₀ value of 1.54 nM. NE-100 attenuates phencyclidin induced head-weaving behavior or ataxia in experimental animals. It suppresses ER stress-induced cell death by the upregulation of 78-kDa glucose-regulated protein (GRP78). Modulators of sigma receptors are suggested to show activity against SARS-CoV-2, based on interaction of SARS-CoV-2 proteins Nsp6 and Orf9c with sigma receptors.