-- adds detail, conference call comments --
During the trial, the new oral antibiotic significantly outperformed vancomycin, the current standard prescription, which was the primary objective said Summit.
Over two-thirds (66.7%) of those treated showed a sustained clinical response (SCR) against 42.4% for vancomycin.
The statistical superiority was driven by a large numerical reduction in recurrent disease compared with vancomycin, which Summit said was key as recurrence is one of the hardest things to stop.
C.difficile or CDI is a growing danger for patients in hospital, care homes and the wider community.
Annually, there are between 450,000 and 700,000 cases in the US alone, with the elderly and sick especially vulnerable.
One study has suggested it costs US$4.8bn to treat these people.
"The healthcare community is acutely aware of the major threat CDI poses, particularly given widespread antibiotic use and our aging population," said Glyn Edwards, Summit’s chief executive.
The biggest unmet need in CDI treatment is reduce recurring cases, he added and the results from the latest trial had exceeded its ‘wildest expectations’.
"These outstanding clinical data from CoDIFy strongly support the profile of ridinilazole as a narrow spectrum antibiotic.
“There is a vital need for potent new antibiotics, and the potential of ridinilazole has attracted great interest.
Edwards added that the results from the CoDIFy trial were exceptionally encouraging and the aim no is to advance ridinilazole into Phase 3 clinical trials.
Here, the company would evaluate partnership opportunities against the benefit of it forward itself, he added.
Professor Mark Wilcox, at Leeds University and Public Health England's lead consultant on C.difficile added that the latest data indicated ridinilazole could become an important new treatment option for CDI with the potential to reduce the high rates of recurrent disease that remain a key clinical challenge.
CoDIFy was a double blind, randomised, active controlled, multicentre, Phase II clinical trial that evaluated the efficacy of ridinilazole against vancomycin in 100 patients in the US and Canada.
Results from a second CoFIFy trail are due next year, though Edwards said the results announced today would provide the bulk of the quantitative data.
Ridinilazole has already received Qualified Infectious Disease Product, or QIDP, designation and has been granted Fast Track status from the US Food and Drug Administration.
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