BTRN, MGH Clinical Success with End-Stage Renal Disease and Multiple Myeloma
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Thursday April 19, 1:00 pm Eastern Time
Press Release
SOURCE: BioTransplant Incorporated and Massachusetts General Hospital
BioTransplant and Massachusetts General Hospital Announce Clinical Success with End-Stage Renal Disease and Multiple Myeloma
- Advances May Lessen Life-long Use of Immunosuppressive Drugs -
CAMBRIDGE, Mass., April 19 /PRNewswire Interactive News Release/ -- BioTransplant Incorporated (Nasdaq: BTRN - news) and the Massachusetts General Hospital (MGH) announced today the continuing success of a double transplant procedure that frees the patient from the need for whole body irradiation to treat cancer. The procedure also eliminates the need for life-long immunosuppressive drugs to prevent donor graft rejection. Results of the treatment of two patients with end-stage renal disease secondary to multiple myeloma will be presented at the Transplant 2001 Meeting in Chicago on May 14, 2001, by scientists from the MGH.
Multiple myeloma is a cancer of the bone marrow that causes the proliferation of abnormal plasma cells. This disease can lead to reduced levels of red cells and platelets, tumors at multiple sites, kidney or heart failure or life-threatening infections. No rejection episodes have occurred, and both patients continue with normal kidney function without progression of myeloma for over 2.5 years and 6 months respectively, in the absence of chronic immunosuppressive drugs. This represents a significant advance toward the time when transplant recipients can be made tolerant to donors' organs without the risks and costs of life-long immunosuppression.
The treatment uses a less toxic preparation for bone marrow transplant that was developed at the Bone Marrow Transplantation Unit at MGH and is a prototype of BioTransplant's proprietary AlloMune(TM) System for cancer. Patients are prepared for transplant with a combination of mild chemotherapy and antibodies against T cells, the immune cells that are responsible for attacking transplanted tissues. This novel approach allows the patient to accept the donor marrow but preserves most of his or her own marrow, leading to the blended immune system described as ``mixed chimerism.'' The immune systems of the donor and recipient are mixed in a way that prevents rejection of the transplanted kidney by the recipient's body and suppresses an attack by the donor's immune cells on the recipient's organs, a dangerous condition called graft-vs-host disease. While the chimeric state keeps donor cells from attacking the recipient's healthy tissues, cancerous cells are not protected. Additional delayed infusions of donor leukocytes (DLI) can further enhance the anti-tumor effect in chimeric recipients. The MGH and BioTransplant have been studying mixed chimerism and its applications for both inducing tolerance of organ transplants and fighting blood cell cancers for several years.
A. Benedict Cosimi, M.D., Chief of the MGH Transplantation Unit, and Claude E. Welch Professor of Surgery at Harvard Medical School said, ``This is the first time that this has ever been done. We know that tolerance can develop and that some patients have been able to discontinue immunosuppressive therapy but didn't know why. This is the first deliberate up-front effort to create tolerance.'' He noted that two clinical trials are expected to begin this year, one in patients with kidney failure and multiple myeloma and the other in patients with comparatively uncomplicated kidney transplants.
Megan Sykes, M.D., Director of the Bone Marrow Transplantation Section and Professor of Surgery and Medicine at Harvard Medical School observed, ``Our research efforts are focused on creating and improving clinical procedures that will obviate the need for long-term immunosuppressive treatment in the transplantation of cells and organs. The milder conditioning regimen has the potential to enable treatment for a wider range of cancers and blood cell abnormalities.''
In further studies presented at the meeting by Juanita Shaffer, blood cells were taken from the patients to monitor their T cell recovery and immune responses to donor cells. Results confirm that mixed chimerism may be vital for the initial acceptance of organ transplants and the successful treatment of blood cancers.
Elliot Lebowitz, Ph.D., BioTransplant's President and C.E.O. said, ``We are excited by the results of these studies that suggest we are approaching the day when patients receiving transplants and cancer therapy can do so without life-long immunosuppression. We will continue to develop our AlloMune Systems that seek to break new ground in the treatment of malignancies. We are progressing toward commercialization of these systems as we build on our successes in the clinic''
Previously, U.S. patents (nos. 6006752 and 5876708) entitled ``Mixed Chimerism and Tolerance'' and ``Allogeneic and Xenogeneic Transplantation'' were issued and licensed exclusively to BioTransplant. The company believes that this technology will significantly expand the number of blood cell cancers and organ transplant patients who can be treated, produce fewer side-effects in these patients and reduce or eliminate the need for long-term immunosuppressive drug treatments.
BioTransplant's AlloMune Systems are also under evaluation for therapy- refractory lymphoma. By transplanting donor bone marrow, the AlloMune System for cancer applications is designed to more aggressively attack tumor cells than the patient's own immune defenses. Additional, potential indications for the AlloMune family of products include hematological disorders, autoimmune diseases and other types of cancer. BioTransplant is developing the AlloMune System for kidney transplantation to facilitate organ acceptance without the need for long-term immunosuppressive anti-rejection drugs. The company has previously demonstrated long-term (multi-year) survival of fully mismatched and life supporting donor kidney grafts in non-human primate models without chronic immunosuppression.
The Massachusetts General Hospital, established in 1811, is the original and largest teaching hospital of the Harvard Medical School and conducts the largest hospital-based research program in the United States. The MGH has major research centers in transplantation biology, the neurosciences, cardiovascular research, cancer, AIDS, cutaneous biology and photomedicine. Along with the Brigham and Women's Hospital, the MGH is a founding member of Partner's HealthCare System, Inc. an integrated health care delivery system comprising the two academic medical centers, specialty and community hospitals, a network of physician groups and non-acute and home health services.
BioTransplant Incorporated utilizes its proprietary technologies to re- educate the body's immune responses to allow tolerance of foreign cells, tissues and organs. Based on this technology, the Company is developing a portfolio of products for application in a range of medical conditions, including organ and tissue transplantation, and treatment of cancer and autoimmune diseases, for which current therapies are inadequate. BioTransplant's products under development are intended to induce long-term functional transplantation tolerance in humans, increase the therapeutic benefit of bone marrow transplants, and reduce or eliminate the need for lifelong immunosuppressive therapy. This release and additional information on BioTransplant is available on the Web at biotransplant.com [snip] |
