(ShareCast News) - Drug discovery and development company Summit Therapeutics outlined its Phase 3 programme for its novel antibiotic, ridinilazole, following recent regulatory meetings with the US Food and Drug Administration and European Medicines Agency.The AIM-traded firm said, with input from the FDA and EMA, it intends to design the Phase 3 clinical programme to evaluate superiority of ridinilazole over standard of care in the treatment of CDI.It said a positive Phase 3 result on superiority has the potential to support the commercial launch of ridinilazole as a differentiated therapy that can both treat initial CDI and reduce disease recurrence."The constructive end of Phase 2 meetings with the US and European regulators have enabled us to design a Phase 3 programme that focuses on evaluating ridinilazole's superiority over standard of care," said CEO Glyn Edwards."This is something we believe would help differentiate our novel class antibiotic from currently marketed CDI treatments and those in late-stage development."Superiority in the combined measure of treatment of initial infection and importantly, reduction in recurrence, could position ridinilazole for front-line treatment of CDI."Summit said it discussed its Phase 3 development programme with the FDA at an End of Phase 2 meeting and through a scientific advice process with EMA.With input from both agencies, the Phase 3 programme is expected to include two trials evaluating ridinilazole as compared to the standard of care, vancomycin, each of which would enrol approximately 700 patients with CDI with the primary endpoint being superiority in sustained clinical response (SCR).It said other planned endpoints will include health economic outcome measures.The Phase 3 trial designs are consistent with the successful proof of concept Phase 2 trial, CoDIFy, in which ridinilazole achieved statistical superiority over vancomycin in SCR, the board explained.SCR is a combined endpoint that measures cure at the end of treatment and a lack of recurrence in the 30 days after treatment.FDA reportedly also confirmed that ridinilazole would be eligible for Priority Review based on its QIDP designation."As we continue to evaluate our options to maximise the value of ridinilazole, our stronger financial position following the DMD programme partnership with Sarepta Therapeutics means Summit has more time to fully explore all options," Edwards continued."These include potentially entering into a collaboration with a third party or securing meaningful non-dilutive funding from government and charitable organisations."In parallel, activities to prepare ridinilazole for Phase 3 trials continue with these anticipated to start in the first half of 2018."