Table 3.

Critical factors affecting the decision of changing current disease-modifying therapy for multiple sclerosis

Factors suggesting to switch from a first line DMT to another	Tolerability/safety issues
	Suboptimal efficacy with disease activity not suitable for escalation to a second line DMT
	Persistent high-titre neutralizing antibodies in patients treated with interferon beta
Factors suggesting to switch from a first line to a second line DMT	RR MS patients experiencing at least one relapse and with an active MRI during the previous year on treatment
	RR MS patients transitioning to the secondary progressive phase with evidence of relapses or MRI activity
Factors suggesting to switch from a second line DMT to another or to a third line DMT	RR MS patients continuing to experience relapses
	Progressive forms of MS with relapses and/or active MRI despite treatment
	Safety issues (e.g., patients on natalizumab at high risk of developing progressive multifocal leukoencephalopathy)
Factors suggesting to switch from a second line to a first line DMT	Tolerability/safety issues
	Risk perception of patient

DMT: Disease-modifying therapy; RR: Relapsing-remitting; MS: Multiple sclerosis.