The FDA issued a Warning Letter to Cue Health on May 10, 2024, after an inspection revealed the company made changes to these tests and these changes reduced the reliability of the tests to detect SARS-CoV-2 virus.
I'm almost certain those changes were to reduce production costs. This is a widespread endemic (no pun intended) across many industries.
Per https://www.fda.gov/inspections-compliance-enforcement-and-c..., it looks like the FDA is unhappy that Cue did something to identify whether the cartridge went outside of the allowed temperature parameters in transit (CP-4166 says that the seller is responsible if a device malfunctions due to damage in transit) and didn’t test each lot as much as they were supposed to or maybe used a lower accuracy threshold than stated in their claims.
I'm almost certain those changes were to reduce production costs. This is a widespread endemic (no pun intended) across many industries.