MPN Workshop of the Carolinas 2024 | Serum albumin as a dynamic treatment-specific surrogate for outcomes in rux-treated pts with MF

Yeah. So this is a bit of a passion project, I think, you know, for a long time I think the idea and something we still talk about is, is how do you know that a patient is benefiting from ruxolitinib or not?

You know, like in many cancers, we give agents and we assess for complete responses. Does the tumor go away? Right. And I don’t think we have that with myelofibrosis. 

We don’t have you know…if you look in the bone marrow a lot of times with ruxolitinib or other agents, we see really the same disease that’s ongoing in the bone marrow, and that’s unfortunate because we know that patients are clinically benefiting. They feel better, right?

And so we have some metrics that we can tell are patients are benefiting. We can see that the spleen volumes decrease, we do that by physical exam, but in practice we’re not doing spleen MRIs that frequently. We know that patients symptoms improve, and we have validated questionnaires that help to to kind of establish how much symptoms are improving.

But unfortunately there’s some, you know, subjectivity to symptoms. And with spleen volume, not everyone has a big spleen or a huge spleen that we can really adequately measure.

And so we thought about looking at a different metric, and albumin really came up as something that, one, we have readily available on normal labs, and two, is a marker of inflammation. We know myelofibrosis is an inflammatory disease, ruxolitinib is an anti-inflammatory therapy. Also, albumin measures kind of nutritional optimization, and we believe that ruxolitinib allows patients spleens to shrink so they eat better, they feel better, they’re more nutritionally optimized. 

And so we went in and looked at albumin and kind of how it changes in response to ruxolitinib and whether or not that change actually was predictive of outcomes. And interestingly, it was in ruxolitinib-treated patients.

So in patients that were treated with rux whose albumin either stayed the same or got better, they did much better than those patients whose albumin actually went down. And when we looked at non-ruxolitinib treated patients we didn’t see the same pattern.

So we think this is something that’s unique to ruxolitinib and may be kind of a quote unquote poor man’s way of assessing response to rux. So if you have a patient who’s on rux, you feel like they’re doing well, you can kind of check their albumin over time. If that looks like it’s increasing or maintaining, then that can give you some reassurance that the therapy may be working.