What does it mean to be MRD negative?

What does it mean to be MRD Negative?

what is mrd negativity? A lot of people are talking about MRD., MRD. means minimal residual disease. And if you cannot identify any residual disease, then that's obviously a great thing.

That translates with longer progression free and also overall survival. The definition for that comes from work that was done and published in the International Myeloma Work Working Group, and it was also implemented in the NCCN guideline. And it says that you have to rule out one myeloma cell in hundred thousand investigated cells. Another way of saying that is 10 to -5 negativity.

There are newer tests that can have a higher sensitivity. They can rule out one cell in a million. There are also studies indicating that if you have these more sensitive technologies and you still cannot find any disease cells, that means the patient is 10 to -6 negative. The progression free survival is longer compared

to if you have a group of patients, up to 10 to -5 negative.

But the definition is set to 10 to -5. So anything better than that is just an improvement of the clinical outcomes.

So the IMWG criteria talks about MRD negativity where the first thing is to think about MRD negativity, you need to be in a complete response or better.

So you need to have reached an IMWG complete response criteria definition and then you can look to see are you have MRD negative or not MRD negativity by IMWG criteria is four different ways to look at it. MRD by flow So that is by the next generation flow that I talked about where it's one in 100,000 cells and no, no, myeloma cells are detected in that.

The next one would be next generation sequencing MRD so MRD by sequencing and that one would be with using tests like the cloneSEQ or adaptive, the third one would be next generation flow or sequencing with imaging as well. So if you're MRD negative by flow or sequencing plus imaging, then that's another level of, you know, no evidence of disease.

And then the third last one, fourth one would be sustained. MRD negativity and we hear a lot about this word, and when we talk about sustained MRD negativity, we are talking about two time points, whether it's by next generation flow, or next generation sequencing, but two time points more than one year apart that are negative and then that constitutes sustained MRD negativity