FDA Warning Letter Highlights Process Validation Failures

The U.S. Food and Drug Administration (FDA) has issued a warning letter to HTO Nevada, Inc., dba Kirkman for significant shortcomings in process validation and production controls. Citing 21 CFR 211.100(a), the agency said the company failed to establish adequate procedures to ensure drug products meet required standards for identity, strength, quality and purity.

Inspectors found that key manufacturing parameters were not included in the firm’s process validation. Several quality-critical parameters were also missing from operating procedures and batch documentation. The FDA additionally noted insufficient qualification of production equipment.

The agency emphasised that process validation must follow a lifecycle approach, starting with product development and control strategy design, followed by process qualification to demonstrate consistent performance.

The FDA required the company to conduct risk assessments for products already on the market and take corrective measures if needed, including potential recalls or customer notifications. It also recommended engaging a qualified CGMP consultant to help address compliance gaps.

09-03-2026