Here's more on anti-angiogenesis:
'Starving' Cancers a New Approach to a Cure
By JEFF NESMITH
c.1998 Cox News Service
WASHINGTON -- Cancer researchers, drug firms and biotech
research companies are rushing to identify and test substances that
may someday be used to treat cancer by starving it of its blood
supply.
But that approach, which is known as antiangiogenesis and has been
called a ''fourth route'' in cancer therapy, is still many experiments
away from being available to treat cancer patients, researchers said
Monday.
One cancer patient, an Illinois history professor, said his tumors
shrank dramatically after he took an antiangiogenic compound.
Previously, chemotherapy, radiology and surgery had failed to stop the
spread of his sarcomas, said Barry Riccio.
''I am convinced that had I not been on the drug, I would be much,
much worse off than I am now,'' said Riccio, who receives a drug
called vitaxin from researchers at Ixsys, a San Diego, Calif., biotech
company.
Patent Office records show that over 33 substances have been
patented for use in treating disease by influencing the growth of new
blood vessels. In some cases, such as burn victims or persons
suffering from diabetes, a doctor may want to stimulate the growth of
new blood vessels.
Large and small drug companies in the United States, Europe, Japan
and Australia all have invested in the research, the patent records
show.
Antiangiogenesis research has been energized for the last decade by
the understanding that the rapid and proliferative growth of tumors
requires a large supply of blood.
Long before a tumor's presence is apparent to the victim, it has started
to direct his or her body to construct new blood vessels that will bring
in the necessary nourishment.
To do this it releases chemical signals which ''turn on'' a nearby blood
vessel, inducing it to start growing a branch in the direction of the
tumor. As the tumor grows, more and more new branches must be
constructed to keep its voracious appetite satisfied.
A substance that could interfere with this process might join
chemotherapy, radiology and surgery as a fourth and completely new
way to treat cancer, some scientists think.
The New York Times reported Sunday that two substances,
angiostatin and endostatin, may be used someday to interfere with a
tumor's ability to have the new blood vessels installed for its benefit.
In reaction to the story, telephones at a the offices of the Rockville,
Md., manufacturer of angiostatin and endostatin were ringing off the
hook Monday as desperate cancer patients sought to get in line for
treatment. The company's stock went up more than tenfold in a few
hours Monday.
However, it could be close to two years before any human being
receives either drug, said Nelson Campbell, chief financial officer of
Entremed Inc., the 52-employee firm.
And then the substances likely will not be administered to cancer
patients, but to healthy volunteers who will take them in a ''Phase I''
trial designed to uncover unwanted side effects, Campbell said.
''We have to do formal pharmacology and toxicology testing on
animals before we'll be able to take the first step toward testing in
humans,'' Campbell said, ''and that has not begun yet.''
He estimated the company was ''12 to 18 months'' of animal tests
away from even asking the federal Food and Drug Administration for
permission to give endostatin and angiostatin to healthy human
volunteers.
Meanwhile, first-phase human trials have been completed on vitaxin
and Ixsys expects to begin Phase II trials, which test a drug's
effectiveness, within six months, said William Huse, president of the
San Diego firm.
Riccio, an Eastern Illinois University history professor, said he
approached Ixsys after reading of vitaxin and asked to be included in
the Phase I trial. Chemotherapy, radiation and surgery had failed to
stem the growth and spread of his tumors, he said.
''When the trial was over, my tumors began to grow, so I asked to be
allowed to resume taking vitaxin,'' Riccio said Monday in a telephone
interview. ''I feel much better than I did 9 months ago, before the trial
began. Some of the tumors have shrunk and others have stabilized.''
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