Rifaximin for Preventing Relapse of Clostridium Associated Diarrhoea (RAPID)

• Difference in % relapse between Rifaximin and placebo at 12 weeks [ Time Frame: 12 weeks ] [ Designated as safety issue: No ]
  The difference in % relapse between Rifaximin and placebo at 12 weeks
  
  

• Bowel symptoms [ Time Frame: 12 weeks ] [ Designated as safety issue: No ]

  Secondary endpoints:

  Clinical:

  1. Bowel symptoms Average daily stool frequency and consistency for each month after start of treatment will be compared for active versus placebo using Students t Test assuming a normal distribution which is likely given the large numbers. In the event of a non-normal distribution the Mann-Whitney U test will be used. A similar approach will be taken for comparing
  2. Length of stay on active versus placebo
  3. The difference in relapse of CDAD within 6 months of start of therapy will be assessed using a continuity-corrected chi-squared statistic or Fisher's exact test
  
  

Aims i) To examine efficacy of a follow-on course of Rifaximin given after a successful initial course of standard treatment, in the prevention of relapse in C. difficile associated diarrhoea (CDAD).

ii) To examine changes in faecal microbiota in patients given Rifaximin vs. Placebo.

Treatment 4 weeks treatment with Rifaximin or Placebo tablets. Tapering dose starting with 2 x 200mg tablets three times a day (total = 1.2g per day) for the 1st 2 weeks, reduced to 1 x 200mg tablet three times a day (total = 0.6g per day) for the 2nd 2 weeks.

Primary endpoint: The difference in % relapse between Rifaximin and placebo at 12 weeks