FDA CDER encourages submission of a human factors validation protocol for review. What is the most appropriate mechanism for the feedback?

Submitting a human factors validation protocol to the Investigational New Drug (IND) application is indeed the most appropriate mechanism for obtaining FDA feedback. This approach allows the FDA to review the protocol in the context of the specific clinical development plan and ensure that the proposed human factors studies are aligned with regulatory expectations. The IND process is designed to facilitate communication and collaboration between the sponsor and the FDA, enabling the agency to provide guidance on aspects critical to the safety and efficacy of the drug under investigation.

This submission also allows the sponsor to incorporate any feedback early in the development process, which can help streamline the eventual New Drug Application (NDA) submission. The feedback received can provide valuable insights into how well the protocol meets regulatory requirements for usability, which is essential in ensuring that the drug's labeling and use instructions are clear and effective for the intended user population.

Other methods, such as contacting the FDA directly over the phone or posting the protocol for public comment, do not offer the structured and formal opportunity for feedback as submitting through the IND does. Phone conversations may provide quick replies but lack the formal documentation that is crucial for regulatory affairs. Similarly, public comment mechanisms do not focus on the specific developmental context of a single drug and are not tailored to assist individual sponsors directly.