GeneralLast reviewed April 2026

Pre-Approval Inspection(PAI)

An FDA facility inspection conducted before approval of an NDA, BLA, ANDA, or equivalent to verify cGMP readiness and submission accuracy.

Usage Examples

The PAI verified the commercial manufacturing facility's cGMP readiness for NDA approval.
An OAI outcome from the PAI required CAPA completion before FDA could approve the application.

What is PAI?

A Pre-Approval Inspection (PAI) is an FDA on-site facility inspection conducted before approving a drug marketing application. PAIs verify that the facility is cGMP-compliant, that submission content accurately reflects actual manufacturing capability, and that data submitted in the application is authentic and reproducible. PAIs are typically triggered by first approval of a new facility, first approval of a new product, or major manufacturing changes.

PAI scope covers: data integrity verification (comparison of raw data to submission content), cGMP systems assessment (quality, facilities, equipment, materials, production, packaging, laboratory), and specific review of processes supporting the pending application. Outcomes range from NAI (No Action Indicated) through VAI (Voluntary Action Indicated) to OAI (Official Action Indicated) — an OAI finding typically blocks approval until remediated.

Regulatory Context

This term appears most often in general workflows where submission quality, regulatory evidence, and audit readiness depend on consistent language. It is commonly referenced alongside 21 CFR 211, FDCA, CPG 7356 002.

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When This Matters

The PAI verified the commercial manufacturing facility's cGMP readiness for NDA approval.
An OAI outcome from the PAI required CAPA completion before FDA could approve the application.

Common Mistakes

Relying on generic terminology without mapping to the active jurisdiction context.
Skipping cross-links between terms, tools, and active regulatory references.
Failing to maintain a single source of truth for regulatory definitions internally.

Related Regulations

21 CFR 211FDCACPG 7356 002

Frequently Asked Questions

Typically for first-time approvals of a drug or manufacturing facility, major manufacturing changes requiring PAS filing, or high-risk product classes. Not every approval requires a PAI — FDA uses risk-based scheduling.

Official Action Indicated — significant cGMP or data integrity issues identified. OAI typically blocks application approval until the observations are corrected and FDA reclassifies the inspection. This can delay approval by months.

Ensure all batch records, laboratory data, and quality system artifacts align with submission content. Pre-PAI readiness reviews, data integrity audits, and tabletop exercises help identify gaps. FDA typically provides 5-10 days notice.