When Warning Letters Spell Trouble

When the FDA finds significant violations of federal requirements, it typically issues a Warning Letter to the responsible firm. The letter identifies the problems—such as inadequate manufacturing practices, misleading claims, or incorrect instructions—and sets a deadline to respond with corrective actions.

Common triggers include:

Inadequate or missing procedures.
Poor record-keeping and documentation.
Insufficient employee training.
Contamination or cross-contamination risks.
Failure to follow written procedures.

Recent themes in warning letters.

Data integrity: A leading cause of citations. Data integrity concerns appeared in 61% of Warning Letters in 2021. Examples include non-contemporaneous microbiology entries, gaps in environmental monitoring, and altered batch records.
OTC example (mid-2025): A Utah-based topical OTC manufacturer was cited for inadequate sampling and component testing, specifically for failing to test incoming raw materials for diethylene glycol (DEG) and ethylene glycol (EG). Inspectors also noted weak water-system monitoring (microbiological control and conductivity) and documentation gaps, signaling a deficient quality system and non-compliance with cGMPs3.

These examples underscore the need for strong compliance practices: complete documentation, trained personnel, robust quality and risk management, routine audits, timely issue resolution, clean facilities, and open communication with regulators.

How Sartorius Can Help

Sartorius solutions help companies stay compliant and protect products from contamination.

Cubis^® II balances — designed to support FDA data integrity principles (ALCOA: Attributable, Legible, Contemporaneous, Original, Accurate).
Picus^® 2 and Tacta^® pipettes — engineered for precise liquid handling and compatibility with ISO 8655 performance requirements; results are traceable when calibrated by an ISO/IEC 17025–accredited laboratory.
Minisart^® and Claristep^® filters — remove particulates prior to analysis to protect HPLC columns and improve result reliability.
Microbiology and sterility tools — Sterisart^® systems for sterility testing, MD8 for microbial air monitoring, and Microsart^® solutions for microbial enumeration and rapid detection.

All are designed to align with GMP and regulatory expectations. By enabling accurate measurements, reliable contamination control, and strong data practices, Sartorius helps maintain product quality, reduce compliance risk, and streamline workflows, so manufacturers can deliver safe, high-quality therapies while avoiding costly deviations and FDA warning letters.

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