Case Study: When Underestimating Risk Leads to a Warning Letter

The DxI 9000 Access Immunoassay analyzer instrument and assays are used to diagnose serious conditions such as Hepatitis B and heart attacks, and to monitor levels of therapeutic drugs such as Digoxin used in treatment of heart failure and atrial fibrillation. In a recent warning letter, FDA cited several examples of incorrect severity assignments,

Severity Rating has been incorrectly selected for many assays’ false result failure modes.

Additionally, FDA found issues with procedures for CAPA, Nonconformances and Design Controls:

1. Criteria for escalating nonconformances to CAPA are not defined clearly

2. No process for assessing risk assessment of individual nonconformances

3. Severity classification of nonconformances released to the field is not adequately defined

4. No criteria for escalating complaints to CAPA based on trend analysis

5. CAPA actions are not verified and validated for effectiveness and additional adverse effect(s) on the finished devices

6. Inadequate procedures for verification and validation of design changes

🎧Listen to a brief audio summary of this case above and lessons QA/RA and Risk professionals can apply in practice.

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Note:

The audio summary was prepared using Google NotebookLM¹, an AI-enabled research tool. Here is the list of resources used for this analysis:

1. FDA: Warning letter, Beckman Coulter Inc., CMS 678042, March 15, 2024.

2. K011920, EMIT 2000 DIGOXIN ASSAY, MODEL OSR4H229, cleared July 2, 2001.

3. K121214, ACCESS ACCUTNI+3 REAGENT AND ACCESS ACCUTN1+3 CALIBRATORS FOR USE ON THE ACCESS 2 IMMUNOASSAY SYSTEM, cleared June 14, 2013.

4. K221225, Access TSH (3rd IS) Assay, DxI 9000 Access Immunoassay Analyzer, cleared November 10, 2022.

5. Beckman Coulter: Therapeutic Drug Monitoring Flyer FL-47564.

1. Google: NotebookLM, accessed June 22, 2025.