article about a vaccine for lymphoma

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Vaccine Yields 89% Survival in Lymphoma Study

Results Could Affect Other Lymphoma, Leukemia Types

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A vaccine given to patients with recurrent mantle cell lymphoma

resulted in an 89% survival rate at 46 months for all of the

patients, according to a new Phase I study.

Although several of the 26 patients with mantle cell lymphoma have

relapsed for reasons that are unclear, " so many of these patients

continue to be alive that it is quite possible the vaccine did

modify the natural history of the disease, " says the study's senior

author Larry Kwak, M.D., Ph.D., chair of M. D. 's Department

of Lymphoma.

Kwak developed the vaccine while he worked at the National Cancer

Institute (NCI) before coming to work at M. D. . The study,

published in the September issue of Nature Medicine, was conducted

by researchers from M. D. and the NCI. " We can't over-

interpret this single study, but these patients may have done better

than expected, " Kwak says.

B cells not needed to prime immune system

The clinical trial focused on the immune system cells of patients

with mantle cell lymphoma, a rare type of non-Hodgkin's lymphoma for

which there is no effective long-term therapy. Typical overall

survival for mantle cell lymphoma is 50% at three years.

Results showed that few, if any, B cells (cells that produce

antibodies in response to tumor cells) are needed to trigger a

response from T cells (cells that activate the immune system).

The discovery overturns the belief that B cells are needed to prime

the human immune system, says the study's first author, Sattva

Neelapu, M.D., an assistant professor in M. D. 's Department

of Lymphoma: " This is the first human cancer vaccine study to see T-

cell responses in the absence of B cells, and this paves the way to

use vaccines in a number of hematological cancers (such as lymphoma

and leukemia) that are treated by eliminating diseased B cells. "

Vaccine is tailored to each patient based on antigens

In the study, patients received the vaccine three months after

treatment with chemotherapy and rituximab (Rituxan®). Rituximab is a

monoclonal antibody drug federally approved for use in non-Hodgkin's

lymphoma. Monoclonal antibodies are designed to latch onto proteins

on the surface of cancer cells and trigger an immune response

against the cells.

Five doses of the vaccine were given at monthly intervals, resulting

in the 89% survival rate. " After the third vaccination, we began to

see T-cell responses. An antibody response to the tumor produced by

recovering B cells was seen after the fourth or fifth vaccination, "

Neelapu says.

Vaccine continues to be studied in other clinical trials

M. D. researchers are working to improve the vaccine before

testing it further.

The vaccine was originally tested for use in follicular lymphoma and

was subsequently licensed to Accentia Biopharmaceuticals. That

company, for which Kwak now consults, is testing the vaccine, known

by the name Biovaxid™, in a Phase III clinical trial. Two other

customized lymphoma vaccines are now being tested in the United

States.