Mastering Labeling Review for NDA and BLA Submissions

Introduction: Why Labeling is Central to Regulatory Approval

Labeling plays a critical role in the regulatory review of New Drug Applications (NDAs) and Biologics License Applications (BLAs). It defines how a product is prescribed, used, stored, and communicated to healthcare providers and patients. For regulators, especially the U.S. Food and Drug Administration (FDA), labeling ensures safety, efficacy, and informed decision-making.

Labeling is not a post-approval formality. It undergoes rigorous scientific, regulatory, and legal review throughout the approval process. Sponsors must prepare labeling materials that comply with current FDA standards, including the Physician Labeling Rule (PLR) and the use of Structured Product Labeling (SPL) in XML format. In this article, we explore the stages, formats, requirements, and best practices in the labeling review process.

Labeling Components in NDA and BLA Submissions

For both NDAs and BLAs, the labeling materials must include the following components:

• Prescribing Information (PI) — main labeling content reviewed under PLR
• Medication Guide (MG) — if required for patient understanding or serious risks
• Patient Package Insert (PPI) — applicable for specific drug classes
• Carton and Container Labeling — graphical elements and required statements
• SPL Files — structured XML-based format for submission

Each of these elements must be accurate, evidence-based, and aligned with the application’s safety and efficacy data.

FDA Labeling Review Workflow

The FDA labeling review process is a multistage activity conducted by the Division of Labeling and Program Support (DLPS) and the Office of Prescription Drug Promotion (OPDP). Here’s a typical workflow:

1. Initial submission of draft labeling at the time of NDA/BLA submission (Module 1.14)
2. FDA reviews labeling for scientific accuracy, clarity, PLR compliance, and risk communication
3. Labeling negotiations between sponsor and FDA, often requiring multiple rounds of edits
4. Final approval of labeling prior to marketing authorization
5. Submission of final SPL versions via ESG (Electronic Submissions Gateway)

According to recent data from ClinicalTrials.gov, labeling-related deficiencies contribute to over 20% of Refuse-to-File (RTF) letters.

Labeling Format Standards, SPL Compliance, and Avoiding Deficiencies

PLR Format: Key Sections of the Prescribing Information

The FDA requires that the Prescribing Information (PI) follow the Physician Labeling Rule (PLR) format, which includes:

• Highlights of Prescribing Information
• Table of Contents
• Full Prescribing Information with 17 required sections

Examples of required sections include:

• 1. Indications and Usage
• 2. Dosage and Administration
• 5. Warnings and Precautions
• 8. Use in Specific Populations
• 17. Patient Counseling Information

These sections must be evidence-based and consistent with clinical trial data submitted in Module 5.

Structured Product Labeling (SPL): XML Format Compliance

All final labeling must be submitted using SPL, which is an XML-based standard adopted by the FDA for digital labeling. SPL submissions must include:

• FDA-approved product identifier (e.g., NDC)
• Unique document IDs and versioning
• Correct tags and standardized vocabulary

Sponsors can use tools like FDA’s Xforms or commercial solutions to validate SPL prior to submission. Incorrect SPL formatting may lead to ESG rejection or a request for resubmission.

Medication Guide and Patient Package Insert Requirements

A Medication Guide (MG) is mandatory when a drug:

• Could prevent serious adverse events
• Has risks that patients should be aware of before use
• Requires adherence for effectiveness

A Patient Package Insert (PPI) is more common with contraceptives and hormone therapies. Both documents must be written at a 6th–8th grade reading level and reviewed by the Office of Communications (OCOMM).

Labeling Negotiation and Common Issues

Labeling negotiation with the FDA is a critical stage. Some common issues include:

• Overstating efficacy or under-communicating risk
• Misalignment with clinical trial populations
• Ambiguous dosing instructions
• Inconsistent safety language across PI and MG
• Outdated terminology or off-label discussions

Sponsors should designate a labeling working group (medical writers, regulatory leads, legal advisors) to handle revisions efficiently.

Carton and Container Labeling: Design and Compliance

Labeling also includes graphical components. These must adhere to 21 CFR 201.10 and include:

• Drug name (brand and generic)
• Strength and dosage form
• Route of administration
• Lot number and expiration date
• Storage instructions
• FDA-mandated warning statements

Mock-ups are reviewed by the FDA’s Product Quality Review Office and must match approved PI content.

Case Study: Labeling Deficiency in a BLA Review

In 2022, a BLA sponsor for a monoclonal antibody received a major amendment delay due to:

• Lack of boxed warning despite high-risk adverse events
• Inconsistent use of terms between PI and PPI
• SPL submission containing unapproved sections

The company had to resubmit all labeling components, triggering an extension of the PDUFA goal date by 3 months.

Labeling Lifecycle Management

Labeling doesn’t end at approval. Sponsors must maintain:

• Annual Reports of changes
• Safety-related labeling change notifications
• Post-approval updates for new indications or dosage forms
• Tracking of competitor label changes (for 505(b)(2) sponsors)

A proactive labeling strategy helps ensure compliance and maintain FDA trust.

Best Practices for Labeling Success

• Involve regulatory and medical writing teams early
• Use FDA labeling guidance and checklists
• Submit editable Word versions during review stages
• Run SPL validations before final ESG submission
• Document labeling negotiations thoroughly

Conclusion: Labeling as a Regulatory and Commercial Asset

Effective labeling is more than a regulatory requirement — it is a bridge between data and prescriber behavior, patient outcomes, and legal protection. A poorly crafted label can delay approval, expose sponsors to litigation, or limit market access. On the other hand, a well-structured, compliant label supports a successful launch and long-term product value.

Invest in labeling expertise — early and consistently — to avoid costly missteps.