Sclerostin is a glycoprotein made in the osteocytes of the bone. It slows down bone formation. It can cross the blood brain barrier and apparently does so increasingly as we age, causing excess production of amyloid. But sclerostin is currently targeted only for bones.
Amgen’s drug Evenity (romusuzumab) targets sclerostin and is prescribed for severe osteoporosis. (At present there do not seem to be guidelines for when to prescribe romosuzumab versus teraparatide, another anabolic that works primarily by stimulating the parathyroid but can also reduce sclerostin – not as much as romosuzumab.)
I did not want to take romosuzumab because of the cardiac warnings. But, my osteoporosis is severe and romosuzumab has been shown to increase bone formation more than any other treatment currently availale. I re-looked at my genetics and saw that I have two SNP’s that are homozygous for the risk allele-- these SNP’s control the Wnt signaling pathway. This was revelatory for me because it pointed to an overabundance of sclerostin as a driver of my osteoporosis. (I don’t know if this is common, but it seems that it is not rare) I went from not wanting to take romosuzumab to practically begging for it, and changing my insurance so I could cover it. I’ve now had my first injections.
But I digress. The reason I am posting is that I am trying to understand why there isn’t more heat and light on romosuzumab – or some other sclerostin inhibitor – as a therapy for neuordegeneration.
Could it be that it is because Amgen makes both Evenity and Lecanemab? Lecanemab reduces amyloid in the brain but has failed to show any improvement in cognition, and has risks for brain bleeds. It is very expensive and not very helpful. Does Amgen want to wring out every potential dollar from their Lecanemab investment before bringing something potentially much better? Perhaps they are already working on Evenity 2.0 for the brain? (If not, why not?)
For me personally, I would want to see more attention to this so that I might possibly be able to take romosuzumab beyond the current twelve month protocol. Right now you cannot get more than that, (cost? cardiac risks?) though a few clinicians have been making exceptions.
Anyone have any insights into Amgen, or any thoughts about how to bring more attention to sclerostin as a potential therapy for neurodegeneration?