The FDA’s August 11, 2025 warning letter to LeMaitre Vascular reads like a masterclass in how fundamental water system deficiencies can cascade into comprehensive quality system failures. This warning letter offers lessons about the interconnected nature of pharmaceutical water systems and the regulatory expectations that surround them.

The Foundation Cracks

What makes this warning letter particularly instructive is how it demonstrates that water systems aren’t just utilities—they’re critical manufacturing infrastructure whose failures ripple through every aspect of product quality. LeMaitre’s North Brunswick facility, which manufactures Artegraft Collagen Vascular Grafts, found itself facing six major violations, with water system inadequacies serving as the primary catalyst.

The Artegraft device itself—a bovine carotid artery graft processed through enzymatic digestion and preserved in USP purified water and ethyl alcohol—places unique demands on water system reliability. When that foundation fails, everything built upon it becomes suspect.

Water Sampling: The Devil in the Details

The first violation strikes at something discussed extensively in previous posts: representative sampling. LeMaitre’s USP water sampling procedures contained what the FDA termed “inconsistent and conflicting requirements” that fundamentally compromised the representativeness of their sampling.

Consider the regulatory expectation here. As outlined in ISPE guideline, “sampling a POU must include any pathway that the water travels to reach the process”. Yet LeMaitre was taking samples through methods that included purging, flushing, and disinfection steps that bore no resemblance to actual production use. This isn’t just a procedural misstep—it’s a fundamental misunderstanding of what water sampling is meant to accomplish.

The FDA’s criticism centers on three critical sampling failures:

• Sampling Location Discrepancies: Taking samples through different pathways than production water actually follows. This violates the basic principle that quality control sampling should “mimic the way the water is used for manufacturing”.
• Pre-Sampling Conditioning: The procedures required extensive purging and cleaning before sampling—activities that would never occur during normal production use. This creates “aspirational data”—results that reflect what we wish our system looked like rather than how it actually performs.
• Inconsistent Documentation: Failure to document required replacement activities during sampling, creating gaps in the very records meant to demonstrate control.

The Sterilant Switcheroo

Perhaps more concerning was LeMaitre’s unauthorized change of sterilant solutions for their USP water system sanitization. The company switched sterilants sometime in 2024 without documenting the change control, assessing biocompatibility impacts, or evaluating potential contaminant differences.

This represents a fundamental failure in change control—one of the most basic requirements in pharmaceutical manufacturing. Every change to a validated system requires formal assessment, particularly when that change could affect product safety. The fact that LeMaitre couldn’t provide documentation allowing for this change during inspection suggests a broader systemic issue with their change control processes.

Environmental Monitoring: Missing the Forest for the Trees

The second major violation addressed LeMaitre’s environmental monitoring program—specifically, their practice of cleaning surfaces before sampling. This mirrors issues we see repeatedly in pharmaceutical manufacturing, where the desire for “good” data overrides the need for representative data.

Environmental monitoring serves a specific purpose: to detect contamination that could reasonably be expected to occur during normal operations. When you clean surfaces before sampling, you’re essentially asking, “How clean can we make things when we try really hard?” rather than “How clean are things under normal operating conditions?”

The regulatory expectation is clear: environmental monitoring should reflect actual production conditions, including normal personnel traffic and operational activities. LeMaitre’s procedures required cleaning surfaces and minimizing personnel traffic around air samplers—creating an artificial environment that bore little resemblance to actual production conditions.

Sterilization Validation: Building on Shaky Ground

The third violation highlighted inadequate sterilization process validation for the Artegraft products. LeMaitre failed to consider bioburden of raw materials, their storage conditions, and environmental controls during manufacturing—all fundamental requirements for sterilization validation.

This connects directly back to the water system failures. When your water system monitoring doesn’t provide representative data, and your environmental monitoring doesn’t reflect actual conditions, how can you adequately assess the bioburden challenges your sterilization process must overcome?

The FDA noted that LeMaitre had six out-of-specification bioburden results between September 2024 and March 2025, yet took no action to evaluate whether testing frequency should be increased. This represents a fundamental misunderstanding of how bioburden data should inform sterilization validation and ongoing process control.

CAPA: When Process Discipline Breaks Down

The final violations addressed LeMaitre’s Corrective and Preventive Action (CAPA) system, where multiple CAPAs exceeded their own established timeframes by significant margins. A high-risk CAPA took 81 days instead of the required timeframe, while medium and low-risk CAPAs exceeded deadlines by 120-216 days.

This isn’t just about missing deadlines—it’s about the erosion of process discipline. When CAPA systems lose their urgency and rigor, it signals a broader cultural issue where quality requirements become suggestions rather than requirements.

The Recall That Wasn’t

Perhaps most concerning was LeMaitre’s failure to report a device recall to the FDA. The company distributed grafts manufactured using raw material from a non-approved supplier, with one graft implanted in a patient before the recall was initiated. This constituted a reportable removal under 21 CFR Part 806, yet LeMaitre failed to notify the FDA as required.

This represents the ultimate failure: when quality system breakdowns reach patients. The cascade from water system failures to inadequate environmental monitoring to poor change control ultimately resulted in a product safety issue that required patient intervention.

Gap Assessment Questions

For organizations conducting their own gap assessments based on this warning letter, consider these critical questions:

Water System Controls

• Are your water sampling procedures representative of actual production use conditions?
• Do you have documented change control for any modifications to water system sterilants or sanitization procedures?
• Are all water system sampling activities properly documented, including any maintenance or replacement activities?
• Have you assessed the impact of any sterilant changes on product biocompatibility?

Environmental Monitoring

• Do your environmental monitoring procedures reflect normal production conditions?
• Are surfaces cleaned before environmental sampling, and if so, is this representative of normal operations?
• Does your environmental monitoring capture the impact of actual personnel traffic and operational activities?
• Are your sampling frequencies and locations justified by risk assessment?

Sterilization and Bioburden Control

• Does your sterilization validation consider bioburden from all raw materials and components?
• Have you established appropriate bioburden testing frequencies based on historical data and risk assessment?
• Do you have procedures for evaluating when bioburden testing frequency should be increased based on out-of-specification results?
• Are bioburden results from raw materials and packaging components included in your sterilization validation?

CAPA System Integrity

• Are CAPA timelines consistently met according to your established procedures?
• Do you have documented rationales for any CAPA deadline extensions?
• Is CAPA effectiveness verification consistently performed and documented?
• Are supplier corrective actions properly tracked and their effectiveness verified?

Change Control and Documentation

• Are all changes to validated systems properly documented and assessed?
• Do you have procedures for notifying relevant departments when suppliers change materials or processes?
• Are the impacts of changes on product quality and safety systematically evaluated?
• Is there a formal process for assessing when changes require revalidation?

Regulatory Compliance

• Are all required reports (corrections, removals, MDRs) submitted within regulatory timeframes?
• Do you have systems in place to identify when product removals constitute reportable events?
• Are all regulatory communications properly documented and tracked?

Learning from LeMaitre’s Missteps

This warning letter serves as a reminder that pharmaceutical manufacturing is a system of interconnected controls, where failures in fundamental areas like water systems can cascade through every aspect of operations. The path from water sampling deficiencies to patient safety issues is shorter than many organizations realize.

The most sobering aspect of this warning letter is how preventable these violations were. Representative sampling, proper change control, and timely CAPA completion aren’t cutting-edge regulatory science—they’re fundamental GMP requirements that have been established for decades.

For quality professionals, this warning letter reinforces the importance of treating utility systems with the same rigor we apply to manufacturing processes. Water isn’t just a raw material—it’s a critical quality attribute that deserves the same level of control, monitoring, and validation as any other aspect of your manufacturing process.

The question isn’t whether your water system works when everything goes perfectly. The question is whether your monitoring and control systems will detect problems before they become patient safety issues. Based on LeMaitre’s experience, that’s a question worth asking—and answering—before the FDA does it for you.