Table 5.
JC viral load in biological samples of RRMS patients with infusion number equal to 0 (t0: baseline), range from 4 to 12 (<12 months) and >12 (>12 months)
| Pt (n) | Pt JCV DNA+ (n)a | Pt JCV DNA− (n)a | Urine | Plasma | PBMC | ||||
|---|---|---|---|---|---|---|---|---|---|
| JCV+/JCV− | log10 gEq/mL (range)b | JCV+/JCV− | log10 gEq/mL (range)b | JCV+/JCV− | log10 gEq/106 c (range)b | ||||
| t0 | 22 | 8 | 14 | 4/18 | 4.38 (3.48–4.58) | 3/19 | 2.84 (2.70–3.20) | 3/19 | 2.07 (1.95– 3.72) |
| <12 months | 30 | 8 | 22 | 14/45 | 5.33 (2–6.04) | 3/60 | 1.86 (1.61–2.69) | 4/59 | 1.53 (1–2.66) |
| >12 months | 27 | 14 | 13 | 8/40 | 5.11 (2.94–6.67) | 9/47 | 3.01 (1.52–4.72) | 6/50 | 2.39 (1.48– 4.11) |
| RR | 1.71 | ||||||||
| (95 % CI) | (1.61–2.52) | ||||||||
| p valuec | p = 0.04 | ||||||||
p = 0.04: statistical significant association between number of patients with JC viremia and the treatment with natalizumab for more than 12 months compared to number of patients with JC viremia and the treatment with the same drug for less than 12 months
n number of patients, Pt patients
aPt JCV DNA+ and Pt JCV DNA−: number of patients with or without JCV DNA in at least 1 sample of plasma and/or PBMC and/or urine
bJCV load values were expressed as median (range) of log10 genome equivalent (gEq)/mL in urine and in plasma, and as median (range) log10 gEq/106 cells in PBMCs (gEq/106 c)
cRelative risk (RR) and 95 % confidence interval (95 % CI) statistically significant with a p value <0.05 by χ 2 test