Data Published in Journal of Clinical Oncology Highlights Significant Activity of Micromet's Blinatumomab in Patients with Acute Lymphoblastic Leukemia
European pivotal trial enrolling at leading cancer centers
ROCKVILLE, Md.--(BUSINESS WIRE)--May 17, 2011 - Micromet, Inc. (Nasdaq: MITI) today announced that data from a Phase 2 clinical trial of the Company's lead product candidate blinatumomab in patients with minimal residual disease positive (MRD) acute lymphoblastic leukemia (ALL) were published in the May 16th on-line edition of the Journal of Clinical Oncology (JCO). Results of the study demonstrated that blinatumomab produced durable remissions in front-line adult ALL patients at high risk of relapse. Blinatumomab is the most advanced of a new class of agents called BiTE® antibodies, designed to harness the body's T cells to kill cancer cells.
“ALL patients with residual leukemic cells in the bone marrow following treatment with front-line chemotherapy have a 90% risk of relapse and a resulting poor long-term prognosis," said Professor Max Topp, Department of Internal Medicine II, University of Wuerzburg, and lead author of the publication. "Results from this study show that blinatumomab has the potential to fundamentally change the long-term outcome for this difficult-to-treat disease."
Phase 2 Study Design
The multi-center Phase 2 study evaluated the efficacy and safety of blinatumomab in adult patients with B precursor ALL. Enrolled patients had evidence of leukemic cells in the bone marrow following treatment with front-line chemotherapy, otherwise known as minimal residual disease (MRD). The primary endpoint of the study was molecular complete response, or elimination of MRD below detectable levels. Key secondary endpoints included time to hematological relapse, time to molecular relapse and overall incidence and severity of adverse events. Patients received 15 micrograms per meter squared per day of blinatumomab for 28 days followed by two weeks off therapy over a six week treatment cycle. Patients received up to seven treatment cycles.
Phase 2 Results
21 patients were treated in the study. Of 20 evaluable patients, 80% (16 out of 20) achieved a complete molecular response, all within the first cycle of treatment. A priori a 22% molecular response rate was expected. A subset of the patients in the study received an allogeneic hematopoetic stem cell transplant (HSCT), a procedure that typically carries a high risk of mortality. Notably, all transplanted patients were alive 100-days following the transplant.
"Historically stem cell transplantation is associated with a high mortality rate, approximately 25% in adult patients1,” said Professor Topp. "Data from this study highlights the potential for blinatumomab to improve the outcome of the transplant by improving the physical status of the patient and safely reducing the burden of disease before the transplant."
Overall, blinatumomab was well-tolerated. Most adverse events occurred early, were transient and reversible. The most common clinical adverse events (any grade) were fever, headache and chills. Two patients discontinued treatment due to fully reversible adverse events; a seizure and a syncope (temporary loss of consciousness), respectively.
“These data continue to validate our confidence in blinatumomab's potential as a promising new treatment option for patients with ALL and heighten our excitement in the broad-based development program now on-going in this disease setting," said Jan Fagerberg, M.D., Ph.D., Micromet's Chief Medical Officer.
BLAST: European Pivotal Trial in MRD-Positive Adult ALL Patients
Based on results from the Phase 2 trial, in September 2010, the Company initiated a Phase 2 multi-center, single-arm study, also known as BLAST (Blinatumomab Adult ALL MRD Study of T cell engagement), intended to evaluate the efficacy, safety and tolerability of blinatumomab in up to 130 evaluable adult patients with B-precursor ALL with MRD after treatment with front-line chemotherapy. Patients will receive 15 micrograms per meter squared per day of blinatumomab for 28 days followed by two weeks off therapy over a six week treatment cycle, for up to four treatment cycles. The primary endpoint of the study is molecular complete response. Secondary endpoints include 18 month relapse-free survival rate (for non-transplanted patients) and mortality rate within 100 days after stem cell transplantation. Data from the trial, if positive, is intended to support a market authorization in Europe. The Company currently expects to complete patient enrollment by the end of 2012. Additional information regarding the BLAST study is available at www.micromet.com or the U.S. government's clinical trials database at www.clinicaltrials.gov.
Blinatumomab (MT103) is a next-generation monoclonal antibody designed to direct the body's cell destroying T-cells against CD19, a protein expressed on the surface of B-cell derived acute lymphoblastic leukemias and non-Hodgkin's lymphomas. Micromet has received orphan drug designation from the European Medicines Agency for blinatumomab for the treatment of acute lymphoblastic leukemia, mantle cell lymphoma and chronic lymphatic leukemia and from the U.S. Food and Drug Administration for the treatment of acute lymphoblastic leukemia, chronic lymphocytic leukemia and indolent B cell lymphoma.
About Acute Lymphoblastic Leukemia
Acute Lymphoblastic Leukemia (ALL) is an aggressive cancer of the blood and bone marrow that afflicts 5,760 patients in the U.S. annually2. Patients with ALL have abnormal white blood cells (lymphocytes) that crowd out healthy white and red blood cells and platelets, leading to infection, anemia (fatigue), easy bleeding and other serious effects. The average five-year survival rate for adult ALL patients after first relapse is 7%3. The presence of leukemic cells in the bone marrow following treatment with front-line chemotherapy, also known as minimal residual disease (MRD), is a recognized negative prognostic factor for patients with ALL. There are currently no therapies approved for the treatment of MRD-positive ALL.
Micromet, Inc. is a biopharmaceutical company focused on the discovery, development and commercialization of innovative antibody-based therapies for the treatment of cancer. Its product development pipeline includes novel antibodies generated with its proprietary BiTE® technology, as well as conventional monoclonal antibodies. The Company's lead product candidate blinatumomab (MT103) is currently the subject of a European pivotal trial in patients with minimal residual disease positive acute lymphoblastic leukemia. Micromet has collaborations with a number of leading pharmaceutical and biotechnology companies, including Bayer HealthCare Pharmaceuticals, Boehringer Ingelheim, MedImmune, Merck Serono, Nycomed and sanofi-aventis. Additional information can be found at www.micromet.com.
Safe Harbor Statement
This press release contains forward looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 and other federal securities laws. Any statements contained herein which do not describe historical facts are forward-looking statements that involve risks and uncertainties that could cause actual results to differ materially from historical results or from any future results expressed or implied by such forward-looking statements. These forward-looking statements include statements regarding the potential of blinatumomab as a treatment for patients with acute lymphoblastic leukemia and the scope and enrollment of ongoing clinical trials. You are urged to consider statements that include the words "ongoing," "may," "will," "believes," "potential," "expects," "plans," "anticipates," "intends," or the negative of those words or other similar words to be uncertain and forward-looking. Factors that may cause actual results to differ materially from any future results expressed or implied by any forward-looking statements include the risk that our preclinical data is not confirmed in clinical trials with our product candidates. This factor and others are more fully discussed in our Securities and Exchange Commission filings, including our Annual Report on Form 10-K, and Amendment No. 1 thereof, for the year ended December 31, 2010. We caution you not to place undue reliance on any forward-looking statements, which speak only as of the date they are made. We disclaim any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.
1. Pasquini MC, Wang Z. Current use and outcome of hematopoietic stem cell transplantation: CIBMTR summary slides, 2010. Available at: http://www.cibmtr.org
2. American Cancer Society. Cancer Facts and Figures 2009
3. Fielding A, et al. Outcome of 609 adults after relapse of acute lymphoblastic leukemia (ALL); an MRC UKALL12/ECOG 2993 study. Blood. 2007;109(3):944-950.
Contact: Micromet, Inc.
Jennifer Neiman, 240-235-0246
Director, Corporate Communications
Posted: May 2011