Monoclonals in Therapy
Some researchers have had limited success using monoclonal antibodies in the experimental treatment of cancer patients. In 1981, Drs. Richard A. Miller and Ronald Levy reported partial remission of a lymphoma patient treated at the Stanford University Medical Center. In cancer therapy, monoclonals seek out and kill cancer cells exclusively or deliver drugs to tumor cells. But over the course of treatment, cancer cells seem to lose their sensitivity to the antibodies.
For example, in cases studied at Harvard’s Dana-Farber Cancer Institute, the targets for antibodies on cancer cells vanish when the antibodies are preset, and then reappear again when the antibodies have gone. It is not known exactly why this happens. Furthermore, no one has found characteristic target sites unique to cancer cells, although antigens not normally found in a patient’s tissues have been discovered.
Preliminary results of studies by a group at Dana-Farber and the Children’s Hospital in Boston suggest that monoclonal antibodies can be used to purify bone marrow samples taken from leukemia patients. After the remaining leukemic bone marrow is destroyed by radiation and drugs, the purified marrow can be reinfused into the patients.
The monoclonal antibodies sold by Ortho are being tested for therapeutic applications in bone marrow and organ transplantation. Clinical trials supervised by Otho and elsewhere by competing companies are under way to use monoclonal antibodies for suppressing the immunity of a patient’s system to prevent graft-versus-host rejection in renal transplants.
The monoclonal antibodies are being tested for therapeutic applications in bone marrow and organ transplantation. Clinical trials are under way to use monoclonal antibodies for suppressing the immunity of a patient’s system to prevent graft-versus-host rejection in renal transplants. There were nearly 5000 kidney transplants performed in 1981, the most recent statistic available.
In many organ transplants, it is necessary to suppress the rejection response in the person receiving the transplant. But such general suppression of the immune function leaves the patient susceptible to many other diseases. The precise specificity of monoclonal antibodies shows promise in preventing graft rejection by suppressing only those T cells active in rejecting the graft, leaving the body’s immune system otherwise intact.