Table 1.

Oral agents in RRMS: Overview of mechanisms of action and efficiency.

Drug	MOA	MRI Outcome	Clinical outcome
Laquinimod	– Induction of type ii myeloid cells. – Induction of Th2 cytokine balance. – Increase of BDNF and suppression of TH17 responses. – Attenuation of astrocytic NF-κB activation.	– Reduction of enlarging or new T2 hyperintense lesions. – Reduction of gadolinium enhancing lesions. – Reduction in the loss of brain volume.	– Reduction of ARR. – Modest reduction in the risk of confirmed disability progression.
Fingolimod	– Modulation of S1PR 1, 3–5. – Inhibits egress of lymphocytes. from lymph nodes towards CNS. – Retains Th17 cells. – May reduce astrogliosis and favor remyelination.	– Reduction of enlarging or new T2 hyperintense lesions. – Reduction of gadolinium enhancing lesions. – Reduction of brain atrophy.	– Reduction of ARR. – Reduces the risk of disability progression. – Superior efficacy with respect to ARR compared to IFN-β-1a.
Teriflunomide	– Downregulation of T- and B-cell proliferation by suppression of pyrimidine synthesis.	– Reduction of enlarging or new T2 hyperintense lesions. – Reduction of gadolinium enhancing lesions.	– Reduction of ARR. – Reduces the risk of disability progression.
Cladribine	– Induction of DNA damage via accumulation in monocytes and lymphocytes.	– Reduction of active T2 lesions. – Reduction of gadolinium enhancing lesions.	– Reduction of ARR. – Reduces the risk for disability progression.
BG-12	– Induction of Th2-like cytokines and apoptosis in activated T cell. – Activation of Nrf2 pathway and antioxidant response elements. – Decrease of vascular and intracellular adhesion molecules.	– Reduction of enlarging or new T2 hyperintense lesions. – Reduction of gadolinium enhancing lesions. – Reduction of brain atrophy. – Reduces the number of newhypointense T1-lesions.	– Reduction of ARR and the proportion of patients relapsing. – Reduces the risk of disability progression. – Superior efficacy with respect to ARR compared to GA.

Abbreviations: ARR, annual relapse rate; GA, glatiramer acetate; Ian; interferon, MOA; mechanisms of action, MRI; magnetic resonance imaging.