XOMA There are 3 IL-1 inhibitors on the market associated with the ligand/receptor signaling interaction, anakinra (Kineret; Amgen/Biovitrum), canakinumab (Ilaris; Novartis) and rilonacept (Arcalyst; Regeneron). Anakinra and rilonacept inhibits the effect of IL-1alpha as well as those of beta. As I understand it, diacerein/rhein prevents, the formation of IL-1beta and not the receptors.
Currently there are 3 IL-1 inhibitors on the market in the world. 2 are Mabs and approved in the US in orphan indications. But the third is diacerein, approved in the EU for treatment of Osteoarthritis. The MOA is very different and probably less clean than the Mabs - it works by preventing the creation on the IL-1 receptors (by interfering with ICE - part of the activation system for creating the receptors). The caveats to the pertinence of the diacerein data to Xoma's osteo trial are:
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