Medarex Announces Initiation of Phase 2 Clinical Trials for the Treatment of Ulcerative Colitis and Rheumatoid Arthritis

Presentation of Phase 1 Clinical Data of MDX-1100 at Digestive Disease Week


May 12, 2008, 01:00 ET from Medarex, Inc.

    PRINCETON, N.J., May 12 /PRNewswire-FirstCall/ -- Medarex, Inc.
 (Nasdaq:   MEDX) announced today that it has initiated the Phase 2 clinical
 development program of MDX-1100, a fully human monoclonal antibody that
 targets CXCL10 (also known as IP-10), in ulcerative colitis (UC) and
 rheumatoid arthritis (RA). MDX-1100 could potentially treat UC and RA by
 suppressing the inflammatory process characteristic of these diseases.
     "Based on positive safety data in Phase 1 studies, we have initiated
 patient enrollment in Phase 2 studies that are designed to establish
 proof-of-concept," said Geoffrey M. Nichol, M.B.Ch.B., Senior Vice
 President of Product Development at Medarex. "We are optimistic about the
 broad potential of MDX-1100 to address a range of inflammatory diseases."
     Patients in the Phase 2 randomized, double-blind, placebo-controlled,
 multi-center study in UC will be administered MDX-1100 at 10 mg/kg or
 placebo every 2 weeks for a total of 4 doses. All patients will have active
 UC and will continue standard UC therapy during the trial. The trial is
 expected to enroll 106 patients at multiple sites internationally. The
 primary endpoint of the study is the response rate at 8 weeks. Clinical
 response is based on the Mayo score, a composite endpoint that assesses
 stool frequency and the amount of bloody stool per day as recorded in a
 patient diary, physician global assessment and the assessment of colon
 mucosal inflammation ascertained by endoscopy.
     Patients in the Phase 2 randomized, double-blind, placebo-controlled,
 multi-center study in RA will be administered MDX-1100 at 10 mg/kg or
 placebo every 2 weeks for a total of 6 doses. All patients will have active
 RA while on methotrexate. The trial is expected to enroll 70 patients at
 multiple sites in Europe. The primary endpoint of the study is the ACR20
 response, a composite endpoint that indicates a 20% improvement in RA signs
 and symptoms, at 12 weeks.
     Medarex also announced that results from the MDX-1100 Phase 1 trials
 will be presented at the Digestive Disease Week (DDW) meeting, being held
 May 17 - 22, 2008 in San Diego. The following abstracts are expected to be
 the subject of presentations at the DDW 2008 conference:
-- "A Double-Blind, Placebo-Controlled, Dose-Escalation, Safety and Pharmacokinetic Study of MDX-1100, a Fully Human Anti-CXCL10 Monoclonal Antibody, in Healthy Subjects" (Abstract #T1145) - Poster presentation on May 20, 2008 from 12:00 to 2:00 PM CDT. -- "A Phase 1 Open-Label, Single-Dose, Dose-Escalation Study of MDX-1100, a High-Affinity, Neutralizing, Fully Human IgG1k Anti-CXCL10 (IP10) Monoclonal Antibody, in Ulcerative Colitis" (Abstract #704) - Oral presentation on May 20, 2008 from 3:00 to 3:15 PM CDT. -- "CXCL10 Expression and Biological Activities in Inflammatory Bowel Disease" (Abstract #W1170) - Poster presentation on May 21, 2008 from 12:00 to 2:00 PM CDT. These presentations support the development of MDX-1100 for the treatment of inflammatory diseases such as ulcerative colitis and rheumatoid arthritis. About MDX-1100 MDX-1100 is a fully human antibody that targets CXCL10 (also known as IP-10), a chemokine expressed in association with multiple inflammatory disease indications such as rheumatoid arthritis, inflammatory bowel disease and multiple sclerosis. About Ulcerative Colitis Ulcerative colitis (UC) is a chronic inflammatory bowel disease of the colon and is characterized by inflammation and ulceration of the lining of the colon. Symptoms typically include bloody diarrhea and abdominal pain and in severe cases may require colectomy. According to the Crohn's & Colitis Foundation of America, it is estimated that there are up to approximately 500,000 Americans with ulcerative colitis. About Rheumatoid Arthritis According to the American College of Rheumatology, more than two million Americans suffer from rheumatoid arthritis (RA), a chronic autoimmune disease that develops when certain cells of the immune system inappropriately attack healthy joint tissue, thereby causing swelling, inflammation and damage of joints, as well as systemic inflammation and damage of other tissues. About Medarex Medarex is a biopharmaceutical company focused on the discovery, development and potential commercialization of fully human antibody-based therapeutics to treat life-threatening and debilitating diseases, including cancer, inflammation, autoimmune disorders and infectious diseases. Medarex applies its UltiMAb(R) technology and product development and clinical manufacturing experience to generate, support and potentially commercialize a broad range of fully human antibody product candidates for itself and its partners. Over forty of these therapeutic product candidates derived from Medarex technology are in human clinical testing or have had INDs submitted for such trials, with seven of the most advanced product candidates currently in Phase 3 clinical trials or the subject of regulatory applications for marketing authorization. Medarex is committed to building value by developing a diverse pipeline of antibody products to address the world's unmet healthcare needs. For more information about Medarex, visit its website at Medarex Statement on Cautionary Factors Except for the historical information presented herein, matters discussed herein relating to the development of MDX-1100 constitute forward-looking statements, as defined by the Private Securities Litigation Reform Act of 1995, that are subject to certain risks and uncertainties that could cause actual results to differ materially from any future results, performance or achievements expressed or implied by such statements. Statements that are not historical facts, including statements preceded by, followed by, or that include the words "preliminary"; "potential"; "may"; or similar statements are forward-looking statements. Medarex disclaims, however, any intent or obligation to update these forward-looking statements. Risks and uncertainties include risks associated with the development of MDX-1100, unforeseen safety issues resulting from the administration of antibody products in humans, as well as risks detailed from time to time in Medarex's public disclosure filings with the U.S. Securities and Exchange Commission (SEC), including its Annual Report on Form 10-K for the fiscal year ended December 31, 2007 and its quarterly reports on Form 10-Q. There can be no assurance that such product development efforts will succeed, or whether other developed products will receive required regulatory clearance or that, even if such regulatory clearance were received, such products would ultimately achieve commercial success. Copies of Medarex's public disclosure filings are available from its investor relations department. Medarex(R), the Medarex logo and UltiMAb(R) are registered trademarks of Medarex, Inc. All rights are reserved.

SOURCE Medarex, Inc.