Drug Mechanism of action Development phase References Fingolimod S1P receptor modulator Licensed for clinical practice (remyelinating effect unclear) Miron et al. [44] Hu et al. [45] Dimethyl fumarate Unknown (probably involves upregulation of the transcription factor Nrf2) Licensed for clinical practice(remyelinating effect unclear) Fox et al. [51] Quetiapine Unknown (affinity for D2, 5-HT2A, H1 and 5-HT1A brain receptors) Licensed as an antipsychotic drug for clinical practice (remyelinating effect unclear) Mei et al. [53] Zhang et al. [54] Alemtuzumab Anti-CD52 Awaiting regulatory approval (remyelinating effect unclear) Jones et al. [49] Laquinimod Unknown (probably involves BDNF secretion) Phase III (NCT01707992) Aharoni et al. [59] Comi et al. [60] BIIB033 Blockage of LINGO-1 Phase II (NCT01864148) Mi et al. [28] rHIgM22 Unknown (probably involves the Src family kinase Lyn and PDGFRα signaling) Phase I (NCT01803867) Watzlawik et al. [30] Watzlawik et al. [31] 9-cis-retinoic acid Retinoid X receptor agonist Pre-clinical Huang et al. [39]

Table 1: Drugs with a potentially remyelinating effect under study, their mechanisms of action and development phases. S1P: Sphingosine-1-Phosphate; BDNF: Brain- Derived Neurotrophic Factor; LINGO-1: Leucine-Rich Repeat and Ig domain containing NOGO receptor interacting protein 1; rHIgM22: Human Monoclonal IgM Antibody 22; PDGFRα: Platelet-Derived Growth Factor Receptor α.