FDA issues ABSSSI draft guidance

FDA issued draft guidance on developing drugs to treat acute bacterial skin and skin structure infections (ABSSSIs), impetigo and minor cutaneous abscesses. The draft revises draft guidance on uncomplicated and complicated skin and skin structure infections (SSSIs) published by the agency in 1998.

FDA recommended at least two well-controlled noninferiority or superiority trials for ABSSSI. The agency recommended that noninferiority trials have an active control and a primary endpoint of clinical response or clinical failure at 48-72 hours. FDA also recommended that a "sufficiently conservative" noninferiority margin should be selected to preserve the treatment effect of antibacterial drugs on ABSSSI. The agency calculated the historical treatment effect to be 12% when using an endpoint of cessation of spread of the lesion and resolution of fever at 48-72 hours. FDA added that the sponsor should justify the noninferiority margin selected and discuss the margin with the agency during development. ...