Table 4.

MS Recurrence of Disease Activity After PML

	S1P-RM (n = 20)	Natalizumab (n = 64)	p Value
MS after PML
MS recurrence after PML, n (%)	16 (80)	27 (42.2)	0.003 a
Relapse, n (%)	10/16 (62.5)	26/27 (96.3)	0.004 a
Radiologic progression, n (%)	15/16 (93.8)	19/23 (82.6)	0.306a
Delay between DMT interruption and MS relapse (clinical or radiologic) in months, median (IQR25-75)	4.5 (2.5–10.05)	5 (2.7–14)	0.837b
Disease-modifying therapies after PML
Introduction of a DMT after PML, n (%)	12 (60)	34/54 (63)	0.815a
Number of DMT introduced after PML, median (IQR25-75)	1 (1–2)	1 (1–2)	0.545b
Time to introduction of the DMT in months, median (IQR25-75)	4.9 (2.8–6.7)	7.3 (5.3–11.8)	0.216b
Aggravation of PML post-DMT introduction, n (%)	0/12	0/22	1.0a

Abbreviations: DMT = disease modifying therapies; IQR = interquartile range; NTZ = natalizumab; S1P-RM = sphingosine-1-phosphate receptor modulators.

^aAsymptotic Pearson χ².

^bStudent t test.