HERSHEY, PennsylvaniaAn innovative approach to treating
glioblastoma multiformethe use of a bacterial toxin attached to
interleukin-13 (IL-13)has been tested in animals, and a phase I
study should begin this year, Waldemar Debinski, MD, PhD, said at the
annual seminar of the Council for the Advancement of Science Writing,
a science journalists group.
Dr. Debinski, assistant professor of surgery and of microbiology and
immunology at Pennsylvania State University, where the agent is being
developed, emphasized that there are no effective treatments
available for glioblastoma multiforme, a high-grade glioma.
Mean survival has increased only from 6 to 9 months in 1932, to less
than 12 months in 1989. After 2 years from diagnosis, almost
all patients have died, he said.
The new approach to treating glioblastomas emerged from a discovery
by Dr. Debinskis team regarding IL-13, a growth-hormone-like
cytokine (see figure). They found
that among more than 60 individuals with high-grade gliomas, the
vast majority of patients overexpressed the receptor for inter-leukin-13.
Previous to this finding, no tumor-specific antigens or receptors
were known to be overexpressed in glioblastoma multiforme cells to
such an extent.
This discovery led to the idea of incorporating a Pseudomonas toxin
into IL-13 as a way of delivering a killer dose to the cancer cells.
Studies showed that among mice implanted with human gliomas and then
treated with the toxin-IL-13 combination, 40% remained alive at 5
months, while control mice survived only 6 weeks.
Dr. Debinski hopes that the phase I trial will begin at a number of
institutions in the summer of 2000. We have a collaborative
agreement with the brain tumor consortium supported by the NCI,