20 October 2009

Topics: Onyx, Proteolix, and an Autoimmune Fix?

I read with interest yesterday of Onyx Pharmaceutical's acquisition of Proteolix. (Thanks to VentureLoop for the tweet that tipped me to this.)  Onyx specializes in cancer therapies, and Proteolix has drug therapies that are useful in treatment of both cancer and autoimmune disorders. Among the products in the Proteolix pipeline are immunoproteasome-selective inhibitors.

Proteasomes are barrel-shaped  complexes found in every cell of our body. They are cellular recyclers -- their job is to break down old or unwanted proteins and turn them in to peptide building blocks that can then be recycled to make new proteins. An immunoproteasome is the form this structure takes in cells of the immune system. Normally, they play a role in fighting infections, by breaking down proteins from invaders and using the broken-down pieces as a sort of signal for infection-fighting cells. But increased activity of the immunoproteasome has been implicated in many autoimmune disorders, like rheumatoid arthritis and lupus, where the body attacks itself instead.

Proteasome inhibitors block the action of proteasomes. Since proteasomes are necessary for the day-to-day life activities of cells, inhibiting them can induce apoptosis (cell death), which sounds bad but which is a great thing when you're fighting cancer. And immunoproteasome-specific inhibitors are likewise a great thing when fighting autoimmune disorders.

Immunoproteasome inhibitors are being studied as therapies for autoimmune diseases such as RA and psoriasis (where they've been shown to be effective in animal models) and potentially many other diseases.

One autoimmune disease that I'd hope was an eventual target for this sort of therapy is Goodpasture Disease. OK, I'm admittedly very biased here: I have that disease. It's a very rare autoimmune disorder that causes kidney and lung failure; I was diagnosed with the disorder in 1989. It's a rare enough disease that it's considered an orphan disease for which there are no specifically-targeted therapies.

Encouragingly, there is good evidence (such as this paper from the journal Proteomics [PDF] and this one from the Federation of European Biochemical Societies) and a good chain of reasoning to indicate that immunoproteasome inhibitors would be effective against Goodpasture Disease as well.

I'm happy to see that this novel kind of research into therapies for autoimmune diseases like Goodpasture's is bearing fruit. Onyx Pharmaceuticals has been concentrating on cancer therapies. I certainly strongly encourage Onyx to take advantage of Proteolix's full pipeline and continue the development of proteasome inhibitor-based therapies for autoimmune disorders as well. There are established links between the pathologies of cancers and autoimmune diseases; and there are millions of suffers of  these diseases who could benefit from therapies based on this biotechnology.

Boy, do I love this stuff! The intersection of entrepreneurship, innovation, biotechnology, and the hyper-hyper-local. More, please!

[cross-posted to A Marble Desk]