Regulatory Open Forum

Hi,

Can a CLIA clinical lab create an LDT by obtaining a protocol for a test developed as an LDT by another facility? We found this documented in a few references online but fail to understand how would you satisfy FDA's requirement of LDTs as designed, developed and manufactured within a single lab.

Thank you

Hello Anon,

As you mention Laboratory Developed Test (LDT) this is a U.S. term used so the FDA has been trying to implement control and guidance over these products for many years.  Indeed by definition, the test is supposed to be developed by the laboratory themselves, but in practicality this is not what happens.  Usually manufacturers of "materials" (which use the term loosely) provide a "recipe" or at least provide all of the components needed for a test.  Therefore, different labs use these materials and recipes to complete tests for patients.  There is a lot of history around LDTs, but the tests are supposed to be developed and used in one lab; in reality this is not what happens.

Hi,

Can a CLIA clinical lab create an LDT by obtaining a protocol for a test developed as an LDT by another facility? We found this documented in a few references online but fail to understand how would you satisfy FDA's requirement of LDTs as designed, developed and manufactured within a single lab.

Thank you

Hi,

Can a CLIA clinical lab create an LDT by obtaining a protocol for a test developed as an LDT by another facility? We found this documented in a few references online but fail to understand how would you satisfy FDA's requirement of LDTs as designed, developed and manufactured within a single lab.

Thank you

The problem with LDTs, home brew, is that for years FDA has exercised enforcement discretion based on the original understanding. A lab in a hospital, for example, develops a test for a specific patient and runs it in the hospital lab. FDA, correctly, said that while those test are medical devices, FDA didn't see much value in regulating them.

After years of scope creep, LDTs have become big business. As FDA tries to gain control, there has been a lot of push back for the labs.

FDA has created the, so called, four walls test. The test must be developed and run in the same lab. This means, for example, that larger companies with multiple labs in different locations, cannot share LDTs among labs.

FDA has not been enforcing this rule, as far as I know. In addition, it is not a CLIA rule, so they don't enforce it.

In the end, the practice is forbidden, but frequently occurs.

My recommendation is that you follow FDA's requirement.

Hi,

Can a CLIA clinical lab create an LDT by obtaining a protocol for a test developed as an LDT by another facility? We found this documented in a few references online but fail to understand how would you satisfy FDA's requirement of LDTs as designed, developed and manufactured within a single lab.

Thank you