Medarex Announces Ipilimumab Program Continues to Move Forward
Thursday April 3, 8:00 am ET
Previously-Stated Guidance Remains Unchanged
PRINCETON, N.J., April 3, 2008 /PRNewswire-FirstCall/ -- Medarex, Inc. (Nasdaq: MEDX - News) today issued the following statement in response to the announcement by Pfizer Inc that it was discontinuing its Phase 3 clinical trial of front-line treatment with Pfizer's single-agent anti-CTLA-4 antibody (tremelimumab) compared to chemotherapy in patients with advanced melanoma. Dr. Geoffrey M. Nichol, M.B.Ch.B., Senior Vice President, Product Development of Medarex, stated:
"While Pfizer's tremelimumab and Medarex's ipilimumab have a similar mechanism of action and have been considered by some as similar molecules, it is natural to attempt to draw parallels between the two molecules. However, we feel we need to make certain clarifications. First, the two antibodies are different molecules, and results from one antibody program may not be indicative of results from another program. The molecules are of different IgG antibody subclasses, administered at different doses and dosing schedules, and with different pharmacokinetic parameters.
Second, while, as previously reported, the results from the Phase 2 study under special protocol assessment did not meet the primary endpoint, the three studies in our Phase 2 program were suggestive of ipilimumab's potential for clinical anti-tumor activity based on the totality of the data and are under discussion with regulatory agencies.
Third, Medarex's ongoing ipilimumab Phase 3 program (study 024) for front- line treatment of advanced melanoma is different in design from the Pfizer trial, and at this time, it is too early to draw any clinical conclusions from the Pfizer announcement. In addition, a recent review of our ongoing 024 Phase 3 trial by the Data Monitoring Committee (DMC) indicated that our trial should continue.
Finally, we and our partner, Bristol-Myers Squibb Company, continue to move firmly forward. Our previously-stated guidance remains unchanged and regulatory discussions are pending."
About the Chemotherapy Combination Registrational Trial
Study 024 is a randomized, blinded registrational Phase 3 study designed to evaluate the effect of dacarbazine in combination with 10mg/kg ipilimumab or placebo on progression-free survival and overall survival in 500 patients with previously untreated metastatic melanoma (front-line). Ipilimumab is administered at 10 mg/kg once every three weeks for up to four doses. Subsequently, eligible patients who have not experienced disease progression at week 24 will continue in a maintenance phase where a single dose of ipilimumab or placebo will be administered once every 12 weeks until disease progression. All efficacy analyses, except for overall survival and survival rate at one year, will be conducted when at least 416 events for progression- free survival have been observed in the study and all patients have been followed for at least 12 weeks.
In June 2006, the 024 registrational Phase 3 trial was reviewed by the U.S. Food and Drug Administration (FDA) under a Special Protocol Assessment (SPA) concerning the suitability of the trial design to support regulatory approval. In December 2006, the FDA granted Fast Track status to this program which provides for expedited regulatory review for new drugs that demonstrate the potential to address unmet medical needs for the treatment of serious or life-threatening conditions. Trial enrollment was completed in the first- quarter of 2008.
About Ipilimumab
Ipilimumab is a fully human antibody that binds to CTLA-4 (cytotoxic T lymphocyte-associated antigen 4), a molecule on T-cells that plays a critical role in regulating natural immune responses. The absence or presence of CTLA- 4 can augment or suppress the immune system's T-cell response in fighting disease. Ipilimumab is designed to block the activity of CTLA-4, thereby sustaining an active immune response in its attack on cancer cells.
Comprehensive Clinical Trial Program for Ipilimumab
Ipilimumab is being developed through a joint partnership between Bristol- Myers Squibb and Medarex. Based on nonclinical and clinical studies showing that antibody blockade of CTLA-4 plays an important role in sustaining an active immune response to fight cancer, Bristol-Myers Squibb and Medarex are pursuing a broad clinical development program with ipilimumab evaluating its potential use in advanced metastatic melanoma, as well as prostate, lung, pancreatic, bladder, breast, lymphoma and leukemia cancers. More than 2,000 patients have been treated with ipilimumab as a monotherapy or in combination with other agents in clinical trials.
For further information about ipilimumab clinical trials, please visit www.clinicaltrials.gov. |
