This guidance outlines the recommended format and content for a sponsor or applicant to submit physiologically based pharmacokinetic (PBPK) analyses to the FDA to support applications including, but not limited to, investigational new drug applications (INDs), new drug applications (NDAs), biologics license applications (BLAs), or abbreviated new drug applications (ANDAs). To enable efficient and consistent review, the FDA recommends including the following six sections in a PBPK study report: (A) Executive Summary; (B) Introduction; (C) Materials and Methods; (D) Results; (E) Discussion; and (F) Appendices. The content of each section is described in detail below. This guidance does not address methodological considerations and best practices for the conduct of PBPK modeling and simulation or the appropriateness of PBPK analyses for a particular drug or a drug product. The decision to accept results from PBPK analyses in lieu of clinical pharmacokinetic (PK) data is made on a case-by-case basis, considering the intended uses, as well as the quality, relevance, and reliability of the results from the PBPK analyses.