Dr. Susan Galbraith

I'm sorry, I can't quote you.

It will be.

It will be.

Sorry.

Yeah, sure.

So let me just start with what a SIRD is.

It's a selective oestrogen receptor degrader.

So it fully inhibits the oestrogen receptor.

So it's a full antagonist, but it's also a degrader.

Now, of the drugs that are called oral SIRDs, not all of them are full antagonists.

But camisestrin is a full antagonist of the oestrogen receptor.

So it has no agonistic activity at all.

And it's a very potent degrader.

And we've shown that in the Serena 3 study, which was a window of opportunity study in the early stage, where we did detailed translational analysis, including mass spectrometry analysis of the protein degradation and a measure of the effect of that on proliferation.

So

The data in the second line setting have typically compared with a fulvestrin backbone, and fulvestrin is a previous estrogen receptor degraded, but didn't achieve the same level of degradation at the available dose.

It has to be given intramuscularly once a month because there was not good oral absorption.

So these oral SIRTs are able to, some of them are able to achieve this

more potent level of degradation and that full antagonism and camisestrin is one of those.

But if you look at the second line data sets, we had a study called Serena 2, which is a randomized study comparing against different doses of camisestrin versus fulvestrin.