Antimicrobial Agents for Complicated Skin and Skin‐Structure Infections: Justification of Noninferiority Margins in the Absence of Placebo‐Controlled Trials

The United States Food and Drug Administration requires clinical trial noninferiority margins to preserve a fraction (eg, 50%) of the established comparator drug's efficacy versus placebo. Lack of placebo-controlled trials for many infections complicates noninferiority margin justification for and, hence, regulatory review of new antimicrobial agents. Noninferiority margin clarification is critical to enable new antimicrobial development. In the absence of placebo-controlled trials, we sought to define the magnitude of efficacy of antimicrobial agents and resulting noninferiority margins for studies of complicated skin and skin-structure infection (SSSI).