Antibiotics continue to take a beating as top-line results from Summit Therapeutics Inc.’s phase III study of ridinilazole failed to meet the primary endpoint for sustained clinical response and treating C. difficile infection (CDI). Looking for an upside on its lead candidate’s results, the company noted participants treated with ridinilazole had substantially less recurrence of CDI, the most common cause of diarrhea in hospitalized patients, as compared to those who were administered vancomycin (nominal p-value = 0.0002).