Demise of beta integrin inhibitor
of MLN2201, a compound designed to inhibit vascular inflammation.
XOMA and Millennium Pharmaceuticals have abandoned the development of MLN2201, a compound designed to inhibit vascular inflammation that it was hoped could play a role in the management of a number of cardiovascular diseases.
MLN2201 is a humanised monoclonal antibody directed towards the beta-2 subunit of integrin cell surface proteins found on the surface of white blood cells. In preclinical studies, the antibody inhibited inflammatory responses, apparently by blocking the attachment of beta-2 integrins to their adhesion molecules, limiting the recruitment of leukocytes from blood vessels to tissues and thereby reducing the inflammatory process.
This could potentially be important for limiting the tissue damage that follows any obstruction of blood supply caused by thrombosis: much of this damage results from the inflammatory response triggered when blood flow is re-established. However, XOMA said that MLN2201 had not met the criteria for continued development in a Phase I study.
The two companies are still developing CAB-2, a recombinant protein that inhibits the activation of complement, another pathway involved in vascular inflammation. Both MLN2201 (formerly MLN01) and CAB-2 were the subject of a deal in 2001 in which Millennium agreed to purchase shares in XOMA to the tune of $33.5 million. With the failure of MLN2201, this commitment is now reduced to $20.1 million.
