Mannan-binding lectin-associated serine protease-2, or MASP-2, is a novel pro-inflammatory protein target involved in activation of the complement system, which is an important component of the immune system. The complement system plays a role in the inflammatory response and becomes activated as a result of tissue damage or microbial infection. Inappropriate or uncontrolled activation of the complement system can cause diseases characterized by serious tissue injury. MASP-2 is recognized as the effector enzyme, and is required for the function, of the lectin pathway, one of the principal complement activation pathways. Importantly, inhibition of MASP-2 does not appear to interfere with the antibody-dependent classical complement activation pathway, which is a critical component of the acquired immune response to infection. We are developing MASP-2 antibodies and small molecules and we expect that the intended therapeutic effect can be achieved through multiple routes of administration, including subcutaneous and intravenous administration of our antibodies and oral and intravenous administration of our small molecules.
OMS721, our lead fully human monoclonal antibody targeting MASP-2, is being developed for diseases in which the lectin pathway has been shown to contribute to significant tissue injury and pathology. These diseases are typically characterized by significant end organ injuries, such as kidney or central nervous system injury, when not treated. One group of such diseases is thrombotic microangiopathies (TMAs), including hematopoietic stem-cell transplant-related (HSCT) -related TMA and atypical hemolytic uremic syndrome (aHUS). Another group are complement-associated renal diseases, such as Immunoglobulin A (IgA) nephropathy.
Phase 3 clinical programs are in process for OMS721 in HSCT-TMA, in IgA nephropathy and in aHUS. We also have ongoing Phase 2 clinical trials in patients with HSCT-TMA and in patients with renal disease (including IgA nephropathy). Patient enrollment has opened in a Phase 3 trial in patients with IgA nephropathy and is ongoing in a Phase 3 trial in patients with aHUS.
We hold worldwide exclusive licenses to rights related to MASP-2, antibodies targeting MASP-2 and the therapeutic applications for those antibodies from the University of Leicester, Medical Research Council at Oxford University, and from Helion Biotech ApS. As of February 16, 2018, we exclusively controlled 19 issued patents and 29 pending patent applications in the U.S., and 273 issued patents and 101 pending patent applications in foreign markets, related to our MASP-2 program.