A second well-studied TrkB agonist, LM22A-4 (Massa et al. 2010), is a small molecule identified in silico for its high affinity specific binding to TrkB and has been shown to prevent spine loss in striatal MSNs and to improve motor deficits, in a mouse model of Huntington’s disease (Simmons et al. 2013). This evidence concerns the gene NTRK2 and Huntington disease.