Table 6

Incidence and severity of symptoms of ETEC disease after challenge

ParameterValue for groupProtective efficacy (%)P value (1 sided)a
ACE527 (n = 29)Placebo (n = 27)
Primary endpoint
    No. (%) of subjects with moderate or severe diarrhea15 (51.7)19 (70.4)26.60.12
Secondary endpoints
    No. (%) of subjects with severe diarrhea14 (48.3)16 (59.3)18.5
    No. (%) of subjects with diarrhea of any severity16 (55.2)20 (74.1)25.50.12
    Mean total wt (g) of grade 3–5 stoolsb per subject1163.31,724.635.3
    Median total wt (g) of grade 3–5 stoolsb per subject390.01,128.065.40.09c
    Mean no. of grade 3–5 stoolsb per subject7.29.625.0
    Median no. of grade 3–5 stoolsb per subject5.010.050.00.13d
    No. (%) of subjects with moderate to severe nausea11 (37.9)12 (44.4)14.6
    No. (%) of subjects with moderate to severe vomiting8 (27.6)8 (29.6)6.8
    No. (%) of subjects with moderate to severe abdominal pain/cramps12 (41.4)12 (44.4)6.7
    No. (%) of subjects with moderate to severe anorexia8 (27.6)14 (51.9)46.80.06
    No. (%) of subjects who would have reduced their daily activity if traveling13 (44.4)19 (70.4)36.90.05
    Mean time (h) to onset of diarrhea60.0555.956.80.14c
    No. (%) of subjects with moderate to severe ETEC illness14 (48.3)16 (59.3)18.5
    CFU of challenge strain per g of stool (geometric mean)1.1 × 1062.2 × 10790.00.002
    No. (%) of subjects requiring early antibiotic treatment12 (41.4)16 (59.3)30.20.14
    No. (%) of subjects requiring intravenous fluids8 (27.6)10 (37.0)25.4
Post hoc analyses
    Severity based only on total vol of loose stool
        No. (%) of subjects producing >800 g of grade 3–5 stools12 (41.4)19 (70.4)41.20.03
        No. (%) of subjects producing no grade 3–5 stools9 (31.0)3 (11.1)0.04
    Diarrheal output produced in 24 h following first diarrheal stool
        Mean total wt (g)599.81,102.445.6
        Median total wt (g)310.0488.036.50.06d
  • a Determined by Fisher's exact test unless otherwise indicated; shown only where P < 0.15. As stool number and output data were not normally distributed, nonparametric tests were applied to assess the significance of differences in the median values.

  • b Only stools which contributed to an episode of diarrhea are included.

  • c Determined by Wilcoxon rank sum test.

  • d Determined by Mann-Whitney test.