Table 1 Description of the included clinical trials performed in children

Collet JP et al. 1993 [17]

210 OM-85 BV vs 213 placebo

6-36 mos

Children attending day care centers

1 capsule 10 days/mo for 3 mos

7.5 mos including administration period

No effect at the end of follow-up. During treatment period decrease of risk of RTI (RR 0.52; 95% CI 0.31-0.86)

Jara-Pérez JV et al. 2000 [18]

99 OM-85 BV vs 100 placebo

6-13 yrs

Girls of an orphanage with ARTIs

1 capsule 10 days/mo for 3 mos

6 mos including administration period

Decrease of incidence of ARTIs (p < 0.001); decrease in illness duration, antibiotic consumption, days out of school (p < 0.001).

Gutiérrez-Tarango MD et al. 2001 [19]

26 OM-85 vs 28 placebo

1-12 yrs

RRTIs

1 capsule 10 days/mo; 3 mos. The same six mos later

12 mos including administration period

Decrease of number of ARTIs, antibiotic consumption and duration of ARTI (p < 0.001)

Schaad UB et al. 2002 [20]

120 OM-85 BV vs 100 placebo

26-96 mos

RRTIs

1 capsule/day for 1 mo; 1 capsule/10 days for mos 3, 4 and 5

6 mos including administration period

Lower rate of RRTIs (p < 0.05). largest reduction was in children with ≥ 3RRTIs

Del Rio Navarro BE et al. 2003 [26]

20 OM-85 BV vs 20 placebo

3-6 yrs

ARTIs and low IgG

1 capsule 10 days/mo; 3 mos

6 mos including administration period

Decrease in ARTI occurrence (p < 0.001); decrease in IgG4 level (p < 0.05)

Razi CH et al. 2010 [22]

35 OM-85 BV vs 40 placebo

1-6 yrs

wheezing

1 capsule 10 days/mo; 3 mos

12 mos

Decrease in wheezing attacks (p < 0.001) and of ARTI occurrence (p < 0.001)

Karaca NE et al. 2011 [27]

37 OM-85; 26 no therapy

12-156 mos

IgA deficiency

1 capsule 10 days/mo; 3 mos; no treatment for the following 9 mos. 26 children received one cure-schedule, 11 two or more cure-schedule

50 mos

No difference in RTIs occurrence between the two groups; no development of autoimmune disease