Rapid Test - FDA Analogy:
Person: I want a pair of binoculars to see the moon when hiking
FDA: Great but do they allow you to see Pluto?
P: Umm, no…?
FDA: ah, well, if they can’t help you see Pluto, we deem them illegal for use in the US.
P: What?
FDA: Yep. Get a telescope
Person: I want a pair of binoculars to see the moon when hiking
FDA: Great but do they allow you to see Pluto?
P: Umm, no…?
FDA: ah, well, if they can’t help you see Pluto, we deem them illegal for use in the US.
P: What?
FDA: Yep. Get a telescope
This is an analogy to point out how ridiculous it is that the FDA continues, to this day, to require comparison of a rapid antigen test to PCR when they have entirely different qualities and uses.
If FDA wasn’t so stubborn, they’d make the comparison test a BinaxNoW.
If FDA wasn’t so stubborn, they’d make the comparison test a BinaxNoW.
Use a high bar against BinaxNoW.
Here, Simple:
For authorization, a new rapid test must achieve 95% sensitivity compared to Abbott BinaxNOW (since we’ve already deemed it appropriate), and must have fewer than 1 in 2000 false positives.
Here, Simple:
For authorization, a new rapid test must achieve 95% sensitivity compared to Abbott BinaxNOW (since we’ve already deemed it appropriate), and must have fewer than 1 in 2000 false positives.
This alone would immensely streamline rapid test authorizations and not force companies to skew their clinical trials and offer FDA data that is effectively useless (but FDA considers it - erroneously - useful)
And to be clear - this requirement to skew the clinical trials or fail is what has stalled so many rapid tests.
What do I mean by this? As long as you are comparing an Ag test to a PCR, you have to selectively and very carefully choose who you are going to allow into your clinical trial. If you don't skew the trial, you'll get people at all different PCR Ct values. ...
And that will make it look like the rapid tests are missing a lot of people. But the reality is, rapid tests detect people with high viral load who are infectious and are thus the most important to detect in real time. PCR detects people for weeks after they are infectious.
so this is a simple problem - if PCR lasts positive for weeks after someone leaves isolation and rapid tests are specific to the time of infection when someone needs to isolate, then the FDA is forcing clinical trials that selectively recruit certain ppl at high virus loads.
Better to just compare to a BinaxNOW. Then you are comparing apples to apples. And not apples (rapid) to orange (PCR)... which have different analytes and different kinetics.
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