Companies Ask Changes in Draft PBPK Guidance

AbbVie says FDA should modify its draft guidance on using physiologically based pharmacokinetic (PBPK) analyses in biopharmaceutics applications for oral drug product development, manufacturing changes and controls, to include recommendations for PBPK model-based biowaivers or safe-space applications in cases where permeability is the limiting factor controlling the appearance of the drug in the systemic circulations. The company also recommends the guidance include food effect considerations and includes specific technical comments.

In its letter, Janssen says it is very supportive of the proposed guidance and believes that when it is finalized all stakeholders will realize significant benefits. The comment also raises technical questions and suggestions.

Bayer says the draft should be more specific on how PBPK approaches may reduce the number of in vivo studies to support regulatory assessment. And it makes specific comments.

Apotex submitted a chart with specific technical comments.