Interim Policy on Compounding Using Bulk Drug Substances Under Section 503A of the Federal Food, Drug, and Cosmetic Act | Shudarsana Company

FDA Issues Interim Policy on Compounding Using Bulk Drug Substances Under Section 503A of the FD&C Act

In January 2025, the U.S. Food and Drug Administration (FDA) released updated guidance titled “Interim Policy on Compounding Using Bulk Drug Substances Under Section 503A of the Federal Food, Drug, and Cosmetic Act” to clarify the circumstances under which human drug products can be compounded using bulk drug substances. This policy aims to address ongoing challenges in compounding practices while ensuring public health protection and maintaining drug quality standards.

Background on Section 503A

Section 503A of the FD&C Act provides specific conditions under which licensed pharmacists and physicians can compound drugs for human use without following certain FDA requirements, such as new drug approval, current good manufacturing practice (CGMP) regulations, and adequate directions for use. The intent of Section 503A is to support the availability of compounded medications for patients who have unique medical needs that cannot be met by commercially available products.

To qualify under Section 503A, compounded drugs must:

• Be compounded by a licensed pharmacist in a state-licensed pharmacy or a federal facility, or by a licensed physician.
• Be made using bulk drug substances that meet the requirements outlined in the policy.
• Not be compounded regularly or in inordinate amounts, or be essentially a copy of an FDA-approved drug.

Bulk Drug Substances and the 503A Bulks List

Bulk drug substances are the active ingredients used in drug compounding. Under the interim policy, the FDA outlines three key criteria for acceptable bulk drug substances:

1. USP or NF Compliance: The substance must comply with an applicable United States Pharmacopeia (USP) or National Formulary (NF) monograph, if one exists.
2. FDA Approval Status: The substance must be part of an FDA-approved product.
3. 503A Bulks List Inclusion: If the substance does not meet the above criteria, it must be listed on the FDA’s 503A bulks list, which includes substances evaluated for safety, effectiveness, and medical necessity.

Evaluation of Nominated Substances

The policy establishes a framework for evaluating substances nominated for inclusion on the 503A bulks list. The FDA assesses each substance based on factors such as:

• The medical rationale for its use in compounding.
• The availability of FDA-approved alternatives.
• Evidence supporting its safety and efficacy in compounded drug products.
• Potential health risks associated with its use.

Substances under evaluation are placed on a “Category 1” list until a final decision is made. If a substance is determined to present safety concerns or lacks sufficient evidence of efficacy, it may be excluded from the 503A bulks list.

Conditions and Limitations on Compounding

The FDA clarifies that certain compounding activities are prohibited, even when using bulk substances that meet the outlined criteria:

• Compounded drugs cannot be copies of commercially available products unless there is a documented shortage or a significant difference for the patient (e.g., removing an allergen).
• Compounded drugs cannot be distributed across state lines in amounts exceeding 5% of the total prescription volume unless the compounder is registered as an outsourcing facility.
• Compounding of complex biologics, such as gene therapies, remains outside the scope of Section 503A.

Impact on Compounders and Pharmacies

The interim policy has significant implications for compounding pharmacies and healthcare providers. Pharmacies must carefully track the status of substances on the 503A bulks list and ensure that their compounding practices align with FDA guidance. Additionally, they must maintain detailed documentation to justify compounding decisions, especially when substituting or modifying commercially available drugs.

Regulatory Oversight and Enforcement

The FDA states that it will continue to monitor compliance through inspections and enforcement actions. Compounders found to be in violation of the policy may face warning letters, product seizures, or injunctions. The agency will also work with state pharmacy boards and professional organizations to ensure consistent interpretation and implementation of the interim guidance.

Conclusion

The FDA’s interim policy on compounding using bulk drug substances under Section 503A of the FD&C Act reflects a balanced approach to supporting patient access to necessary compounded medications while maintaining high standards for drug safety and efficacy. This guidance helps streamline the evaluation and approval process for bulk substances and ensures that compounded products meet stringent quality and safety requirements.

Interim Policy on Compounding Using Bulk Drug Substances Under Section 503A of the Federal Food, Drug, and Cosmetic Act | Shudarsana Company

Also Read : Short Note on Regulation (EU) No 536/2014 on Clinical Trials

By Shudarsana Company