Research and development expenses for the quarter ended March 31, 2009 reduced by $2.2 million, from $49.3 million in 2008 to $47.1 million in 2009. General and administrative expenses decreased by $1.9 million for the quarter ended March 31, 2009, from $12.4 million in 2008 to $10.5 million in 2009.

Medarex ended the first quarter of 2009 with about $322.8 million in cash, cash equivalents and marketable securities. Further, as of March 31, 2009, the fair market value of Medarex’s equity interests in Genmab and Celldex Therapeutics were about $85.3 million and about $32.3 million, respectively.

Our first quarter accomplishments and steady progress of key development programs towards proof-of-concept have given us a strong start to an exciting year, said Howard H. Pien, chairman and chief executive officer of Medarex. In addition to furthering our pipeline, we are also capitalizing on value-creating opportunities, including our agreement with Merck and the progress and recent approvals for products developed by licensee partners. Our future prospects will remain strong as we continue to advance the pipeline, leverage multiple opportunities and execute a solid business strategy.

First Quarter Highlights and Recent Developments

During the first quarter, the allowance of an investigational new drug (IND) application was announced for MDX-1203, Medarex’s first antibody-drug conjugate generated using its proprietary technology. Enrollment initiation of the MDX-1203 Phase 1 trial for renal cancer remains on track for mid-2009.

During the first quarter, Medarex received a milestone payment from its partner, MedImmune, LLC, for the allowance of an IND application for MEDI-546, a fully human anti-type 1 interferon antibody for the treatment of scleroderma, a chronic autoimmune disease.

As announced in April, SIMPONI(TM) (golimumab) was approved for commercial sale in Canada and in the United States as a once-monthly subcutaneous treatment for rheumatoid arthritis and other inflammatory diseases and is the second human antibody generated using Medarex’s UltiMAbĀ® technology to receive market approval. In connection with the approval in Canada, Medarex received an undisclosed milestone payment from licensing partner Centocor Ortho Biotech, Inc.

As announced in April, Medarex and its partner, Massachusetts Biologics Laboratories (MBL), signed an exclusive worldwide licensing agreement with Merck & Co, Inc., for the MDX-066 and MDX-1388 antibody combination treatment for C. difficile infection. In return for the world-wide rights to develop and commercialize the antibodies, Medarex and MBL expect to equally divide an upfront payment of $60 million, up to $165 million upon achievement of certain development and regulatory milestones, double-digit royalties on product sales, as well as additional sales-based milestones.

Preliminary MDX-1401 Phase 1 data presented at the 2009 Annual Meeting of the American Association of Cancer Research (AACR) in April demonstrated tumor reduction of 40 percent or more in 25 percent of Hodgkins lymphoma patients (2 of 8) with stable disease. Additional preclinical efficacy and safety data from multiple preclinical programs, including research in the area of antibody-drug conjugates, were also presented at the AACR meeting.

Data from clinical trials of investigational oncology products ipilimumab (Phase 2) and MDX-1106 (Phase 1) will be presented at the 2009 Annual Meeting of the American Society of Clinical Oncology (ASCO) being held from May 29 to June 2 in Orlando, Florida.

Data from the Phase 2 C. difficile program of MDX-066 and MDX-1388 combination treatment for C. difficile infection is scheduled to be presented at Digestive Disease Week (DDW) 2009 being held from May 30 to June 4 in Chicago, Illinois.