Xoma Ltd. announced that Schering-Plough Corporation exercised its right to initiate additional discovery and development programmes under their collaboration for therapeutic antibody products.

Xoma has received up-front payments for each of the additional collaboration programmes and will also receive research funding for each project as well as success based milestones and royalties on the sale of any products that result from the collaboration, a Xoma press release stated.

"We have made significant progress on the first product program since its initiation with Schering-Plough in mid-2006," said Jack Castello, chairman of the board, president, and chief executive officer of Xoma. "We look forward to advancing the new programmes in a similar high quality and expedited manner."

On May 23, 2006, Xoma announced the initiation of a collaboration with Schering-Plough Corporation through its research and development arm, Schering-Plough Research Institute, for therapeutic monoclonal antibody discovery and development. Under the agreement, Xoma is responsible for discovering therapeutic antibodies against multiple targets selected by Schering-Plough. Other Xoma activities are expected to include preclinical studies to support regulatory filings, cell line and process development, and production of antibodies for initial clinical trials. Schering-Plough will make up-front and milestone payments to Xoma, fund Xoma's R&D activities related to the agreement, and pay royalties to Xoma on sales of products resulting from the collaboration.

Xoma is a leader in the discovery, development and manufacture of therapeutic antibodies, with a therapeutic focus that includes cancer and immune diseases. Xoma has royalty interests in Raptiva (efalizumab), a monoclonal antibody product marketed worldwide (by Genentech, Inc. and Serono, SA) to treat moderate-to-severe plaque psoriasis, and Lucentis (ranibizumab injection), a monoclonal antibody product marketed worldwide (by Genentech, Inc. and Novartis AG) to treat neovascular (wet) age-related macular degeneration.