1. Probiotics in IBD: why have they been (somewhat) disappointing
Probiotics in IBD: why have they been (somewhat) disappointing... until now ? Philippe Marteau, MD, PhD Eco... logic group & Medico-surgical department of Digestive Diseases Lariboisière hospital, Paris

2. ? ?
Microbes IBD ?
Which micro-organism ?
Or microbial component ?

3. Probiotics and IBD : RCTs in Humans
POUCHITIS
VSL#3 to prevent pouchitis occurrence or recurrence
A situation where antibiotics are clearly effective

4. Probiotics and IBD : RCTs in Humans
CROHN’s DISEASE
Prevention of postoperative recurrence (POR)
Prevention of relapse of medically treated CD
E. coli Nissle 1917
Saccharomyces boulardii
VSL #3 (abstract from 2000)
Lactobacillus rhamnosus GG
Lactobacillus johnsonii LA1
Small open trial with genetically modified Lactococcus lactis secretingIL-10

5. RCTs Probiotics in Crohn’s disease
Situation
Probiotic n
Months
Relapse
probiotic group
control group P
Reference
POR
VSL #3 28 12
20 % †
40 %† *
Gionchetti et al. abstr CD
ECN
30 %
70 %
Malchow
S. b 6
6.3 %
37.5 %
Guslandi et al.
L. GG 45
16.6%
10.5% NS
Prantera et al.
L GG 75 24
31%
17%
Bousvaros et al.
LA1 98
49% †
64% †
Marteau et al. 70 3
27.9%
33% †
Van Gossum et al.

6. RCTs Probiotics in Crohn’s disease
Situation
Probiotic n
Months
Relapse
probiotic group
control group P
Reference
POR
VSL #3 28 12
20 % †
40 %† *
Gionchetti et al. abstr CD
ECN
30 %
70 %
Malchow
S. b 6
6.3 %
37.5 %
Guslandi et al.
L. GG 45
16.6%
10.5% NS
Prantera et al.
L GG 75 24
31%
17%
Bousvaros et al.
LA1 98
49% †
64% †
Marteau et al. 70 3
27.9%
33% †
Van Gossum et al.

7. RCTs Probiotics in Crohn’s disease
Situation
Probiotic n
Months
Relapse
probiotic group
control group P
Reference
POR
VSL #3 28 12
20 % †
40 %† *
Gionchetti et al. abstr CD
ECN
30 %
70 %
Malchow
S. b 6
6.3 %
37.5 %
Guslandi et al.
L. GG 45
16.6%
10.5% NS
Prantera et al.
L GG 75 24
31%
17%
Bousvaros et al.
LA1 98
49% †
64% †
Marteau et al. 70 3
27.9%
33% †
Van Gossum et al.

8. RCTs Probiotics in Crohn’s disease
Situation
Probiotic n
Months
Relapse
probiotic group
control group P
Reference
POR
VSL #3 28 12
20 %
40 % *
Gionchetti et al. abstr CD
ECN
30 %
70 %
Malchow
S. b 6
6.3 %
37.5 %
Guslandi et al.
L. GG 45
16.6%
10.5% NS
Prantera et al.
L GG 75 24
31%
17%
Bousvaros et al.
LA1 98
49%
64%
Marteau et al. 70 3
27.9%
33%
Van Gossum et al.

9. Why did Probiotics fail so far in Crohn’s ?
Ineffectiveness ?
... And then failure of the selection procedure or model or strategy (rationale on which the trial was decided) ?
Dose ?
Galenics of the tested product ?
End point ? and population treated ?
Statistical power of the trial ?

10. RCTs Probiotics in Crohn’s disease
Situation
Probiotic n
Months
Relapse
probiotic group
control group P
Reference
POR
VSL #3 28 12
20 %
40 % *
Gionchetti et al. abstr CD
ECN
30 %
70 %
Malchow
S. b 6
6.3 %
37.5 %
Guslandi et al.
L. GG 45
16.6%
10.5% NS
Prantera et al.
L GG 75 24
31%
17%
Bousvaros et al.
LA1 98
49%
64%
Marteau et al. 70 3
27.9%
33%
Van Gossum et al.
Lactobacillus johnsonii LA1
Dose : no Ineffectiveness
End point, population : no Galenics of the tested product ?
Statistical power : no Failure of the selection strategy ?

11. RCTs Probiotics in Crohn’s disease
Situation
Probiotic n
Months
Relapse
probiotic group
control group P
Reference
POR
VSL #3 28 12
20 %
40 % *
Gionchetti et al. abstr CD
ECN
30 %
70 %
Malchow
S. b 6
6.3 %
37.5 %
Guslandi et al.
L. GG 45
16.6%
10.5% NS
Prantera et al.
L GG 75 24
31%
17%
Bousvaros et al.
LA1 98
49%
64%
Marteau et al. 70 3
27.9%
33%
Van Gossum et al.
Lactobacillus rhamnosus GG
Galenics : no Ineffectiveness
End point, population : no Failure of the selection strategy !
Statistical power : no

12. Lactobacillus GG to prevent atopic eczema
Kalliomäki et al. Lancet 2001;357:1076-9
% Eczema.
Double blind RCT
132 new borns at risk to develop atopy
L. GG in the mother then baby vs placebo
6 months
follow up 2 years and 4 years
p = 0,038
46%
23%
PLACEBO
L. GG

13. Probiotics
Microflora
Probiotic Health
Immune cells

14. Pharmacological approach of probiotics
Micro-organism
Active components
Targets
Specific effects
Positive
Negative
Pharmacokinetics
Survival
Adhesion / colonisation
Fate of active components

15. Probiotics and IBD : mechanisms ?
Competitive exclusion ?
Immunomodulation ? ….
Production of anti-inflammatory molecules ?
What is reaching the targets in the intestine ?

16. E. coli Nissle 1917
Escherichia coli serotype O6,K5,H1 (non pathogenic)
Mutaflor, Germany
Survive in the GIT
can inhibit the growth of other E. coli or enteric bacteria

17. E. coli Nissle 1917 to prevent relapse of UC : 3RCT
Equivalent to 5-ASA
No placebo controlled trial

18. Inhibition de l’adhésion et de l’invasion de LF82 AIEC
E. coli Nissle 1917
L. casei DN
Intestine-407
CFU invasive LF82/ well x 105
% d’invasion
Boudeau et al. APT 2003
Ingrassia et al. AEM 2005

19. Increased expression of ZO-2 - PK C
E. coli Nissle 1917
Tight junctions
DEFENSINS
Expression of HB D-2
Increased expression of ZO-2 - PK C
Zirrek et al. Cell microbiol 2006
Wehkamp et al. Infect immun 2004

20. Lactococcus lactis to deliver active molecules in the gastrointestinal tract during (experimental) IBD
Genetically modified L. lactis secreting IL-10 or trefoil peptides
--> reduction of experimental colitidies in mice
Steidler L Science 2000
Vandenbroucke et al. Gastroenterology 2004
Human trial ongoing

21. Pharmacokinetics of probiotics in the small bowel Vesa T, Marteau P
Pharmacokinetics of probiotics in the small bowel Vesa T, Marteau P. Alim Pharmacol Ther 2000;14:823-8
L. lactis
Marker (spores of bacillus)
Pharmacokinetics of L. lactis : a bile sensitive strain

22. CONCLUSIONS
... concept = using ingested living micro-organisms to produce and transport molecules of potential therapeutic interest to targets in the intestine
Original pharmacological approach : potential for in vivo production of active molecules, targeting immune cells, presenting immunogenic molecules in a microbial context...
Proven therapeutic effects in specific situations
Extrapolation of effects between products is not possible and one should avoid excessive enthusiasm or scepticism

23. PROGRES
Proof of concept... Probiotics do work in IBD Clinical usefulness ? Yes for ECN in UC
More rational development in ... IBD... should involve knowledge on the pharmacology i.e. galenics, kinetics, mechanisms of action… and target the best patho-physiologic hypothesis

24. Where to shoot ?
E. coli…
Firmicutes +++

25. Thank you Unanswered Questions
How do probiotics work… and how can we select new strains ?
Do probiotics work better after antibiotics ?
Do combinations of strains work better ?