FDA Watch: Agency Resounds the Alarm on Biotin Test Interference

In early November 2019, the U.S. Food and Drug Administration (FDA) updated a previous safety communication about the potential of biotin to significantly interfere with diagnostic tests. The update reiterates the warning to laboratory personnel, diagnostic test developers, providers, and patients that biotin can lead to incorrect lab test results.

Biotin Blinding

Biotin, or Vitamin B7, is a water-soluble vitamin commonly used as an ingredient in multi-vitamins, prenatal vitamins, and dietary supplements marketed for hair, skin and nail growth. Because biotin bonds with specific proteins that can be measured to detect certain health conditions, many laboratory tests rely on biotin-detection based methods and technology. The problem is that biotin can distort laboratory test results leading false highs and false lows, especially when tested patients consume high levels of biotin. And such high consumption is far from unusual given how much of it producers use. Thus, for example, dietary supplements may contain up to 650 times more biotin than recommended daily values.

FDA Reaction to Biotin Interference

In 2017, the FDA issued a safety communication addressing biotin interference with certain in vitro diagnostic tests and has since issued recommendations for laboratory personnel and test manufacturers to minimize the potential for interference. The FDA expressed specific concern about biotin interference resulting in falsely low levels of troponin—the biomarker that aids in diagnosis of heart attacks. Misleading diagnoses as a result of incorrect laboratory results could lead to potentially serious clinical implications, the FDA cautioned.

Since the 2017 safety communication, some laboratory test developers have been successful at minimizing biotin interference of their assays, according to the updated safety communication, but others have not yet addressed it. The troponin problem remains of particular concern as the FDA continues to receive adverse events reports indicating that biotin interference caused falsely low troponin results.

Recommendations for Providers

The newly revised communication lays out recommendations for providers to minimize the risk of biotin interference, including:

• Discussing biotin and multivitamin supplements with patients;
• Notifying laboratories if patients being tested are taking biotin;
• Considering biotin interference as a source of error if laboratory test results do not match clinical presentation; and
• Reporting to the laboratory manufacturer and FDA if they become aware of patients experiencing adverse events following potentially incorrect laboratory test results due to biotin interference.

Recommendations for Laboratories

The communication also recommends that laboratory and testing personnel:

• Be aware that it is difficult to identify samples that contain biotin if assays are used with biotin technology, and to communicate with health care providers and patients to prevent incorrect test results;
• Ask patients if they are taking biotin or a biotin-containing supplement when collecting samples;
• Educate health care providers about biotin interference with laboratory tests;
• Understand that biotin levels higher than the recommended daily allowance of .03 mg may cause significant interference with laboratory tests;
• Be aware that specimens collected from patients taking high levels of biotin may contain more than 100 ng/mL biotin;
• Recognize that currently available data is insufficient to support recommendations for safe testing using affected tests in patients taking high levels of biotin, including about the length of time for biotin clearance from the blood;
• Communicate with the laboratory test manufacturer if there are questions about biotin interference; and
• Be aware of certain troponin assays where the risk of biotin interference has not yet been addressed.

Recommendations for Laboratory Manufacturers

Last but not least, the communication calls on laboratory test manufacturers and developers to:

• Contact the FDA to discuss biotin interference if an assay uses biotin technology;
• Investigate interference from biotin (up to at least 1200 ng/mL biotin) in assays that use biotin technology and determine the lowest concentration of biotin that may cause clinically significant interference with test(s);
• Communicate to customers that may be unaware that a test uses biotin technology and how it may be affected; and
• Contact the FDA with any questions about biotin technology and interference.

For specific measures the FDA wants test makers to implement to manage biotin interference risks, see Diagnostic Testing and Emerging Technologies (DTET), Sept. 23, 2019.

New FDA Approvals

Here’s a look at all the important new product approvals announced from late October through mid-November:

NEW FDA APPROVALS