UPDATE:=Doctors Consider New Approach For Advanced Lung Cancer
June 01 2009 - 10:52AM
Dow Jones News
Some doctors are changing the way they treat lung cancer, the
most lethal type of cancer for both men and women, after new
studies added to the concept of giving certain drugs continuously
to battle the disease in hopes of prolonging lives without the
side-effects of initial treatment with chemotherapy.
Most patients with advanced non-small cell lung cancer are
treated with four-to-six rounds of chemotherapy drugs in order to
slow tumor growth. Chemotherapy kills cancer cells but also affects
healthy cells and can cause significant side effects including
nausea, vomiting and fatigue.
Many doctors also give drugs like Avastin or Tarceva in addition
to chemotherapy. Avastin, marketed in the U.S. by Roche Holding
AG's (RHHBY) Genentech unit, blocks blood vessels that feed
cancerous tumors while Tarceva, also marketed by Genentech along
with OSI Pharmaceuticals Inc. (OSIP), blocks an enzyme involved in
cancer growth.
However, once chemotherapy ends, doctors typically stop all
treatment until the cancer starts growing again or progresses
because giving continuous chemotherapy makes patients sicker from
side effects.
But new studies have suggested that maintaining treatment with
targeted agents like Avastin and Tarceva as well as Alimta, a
chemotherapy drug from Eli Lilly & Co. (LLY) that doctors say
is far less toxic than traditional chemotherapy, could be a new
approach to treating cancer.
Two of the most recent studies were released over the weekend at
the American Society of Clinical Oncology's annual meeting. One
showed patients receiving Alimta after being treated with other
chemotherapy drugs lived for about three months longer than
patients not receiving the drug. The other study showed that adding
Tarceva to treatment with Avastin after patients had been
previously treated with other drugs slowed average cancer growth by
an additional month.
"We don't cure patients," said Roman Perez-Soler, the chairman
of Montefiore-Einstein Cancer Center in New York City. But, he said
doctors no longer have to wait until patients relapse or have their
cancer get worse until they start new treatments.
Most people with lung cancer are diagnosed with advanced stage
disease that cannot be surgically removed or has spread to other
parts of the body. The majority of people with advanced lung cancer
survive less than one year.
Perez-Soler said he currently has just a few patients on
continuous maintenance therapy, but said the new studies provide
additional evidence to treat more patients continuously.
"It's definitely an option to discuss with patients," he
said.
OSI Pharmaceuticals and Genentech have filed an application with
the Food and Drug Administration seeking approval to market Tarceva
as a maintenance therapy.
Gabriel Leung, OSI's president of oncology, said until recently
there were few drugs approved to treat lung cancer so doctors
waited until the disease worsened before adding treatments, partly
because of the side-effects of chemotherapy, but also so they
didn't want to quickly exhaust the supply of available drugs.
"Now with more and more therapy there's not a lot of reason to
wait anymore," he said.
Bruce Johnson, the director of the Dana-Farber Harvard Medical
Center Lung Cancer program, noted that lung-cancer is one of the
most difficult types of cancer to treat. Most patients are
diagnosed with advanced stages of the disease when tumors usually
can't be successfully removed by surgery.
He said such patients will end up getting additional treatment
once their tumors start growing again so treating patients on a
continuous basis essentially moves up the treatment time table. The
ultimate goal of therapy is to stop or slow the growth of lung
cancer for several years but without the significant side effects
of chemotherapy.
Johnson, who is involved in research of an AstraZeneca PLC (AZN)
compound Zactima, which essentially combines the mechanism of
Avastin and Tarceva into one pill, said he's had lung-cancer
patients on Zactima for years. AstraZeneca has said it plans to
soon file for FDA approval of Zactima.
-By Jennifer Corbett Dooren, Dow Jones Newswires; 202-862-9294;
jennifer.corbett@dowjones.com