Bristol-Myers Squibb Co. (BMY) (BMY) is making
progress developing a new drug to assist the body's immune
system in its ability to find and attack cancer cells. The drug
may prove especially effective fighting lung cancer.
Bristol-Myers, the farthest along of at least five
companies pushing ahead with this cancer-targeting approach,
received U.S. approval in March 2011 on a drug that attacks
melanoma by unleashing the body's T-cells to fend off the
cancer. Now, early tests on a Bristol-Myers therapy affecting a
different immune-system lever is showing promise against
advanced lung tumors, tied to more than a quarter of U.S. cancer
deaths yearly, as well as other deadly malignancies.
"This could be a breakthrough for lung cancer," said
Julie Brahmer, an oncologist at the Johns Hopkins Kimmel Cancer
Center in Baltimore.
In an initial trial of 240 patients, the Bristol-Myers
drug, known as BMS-936558, shrunk tumors in 24 of 95 melanoma
patients, 10 of 33 people with kidney cancer and 13 of 75 of
those with advanced lung cancer, according to preliminary
information on the data, gathered in the first phase of tests
usually needed for regulatory approval.
If the result holds up in further trials, the therapy may
become a "backbone" for future combination treatments that
attack cancer by weakening it with chemotherapy while
simultaneously unleashing an immune system assault, said Seamus Fernandez, an analyst at Leerink Swann Co. in Boston. In this
case, Bristol-Myers's drug may reap more than $4 billion a year
in sales, he said.
Final-Stage Trials
"It is the early stage of a whole new field of cancer
therapy," Fernandez said in a telephone interview.
Bristol-Myers rose less than 1 percent to $33.35 at 9:37
a.m. New York time. The shares had declined 5.4 percent this
year before today.
The drugmaker, based in New York, is competing with Merck
Co. (MRK) (MRK) of Whitehouse Station, New Jersey, London-based
GlaxoSmithKline Plc (GSK), Roche Holding AG, of Basel, Switzerland,
and Teva Pharmaceutical Industries Ltd. (TEVA) in Petach Tikva, Israel,
to test the idea in patients. Updated data on Bristol's
experimental compound will be reviewed at the American Society
of Clinical Oncology meeting that starts June 1 in Chicago.
The preliminary results are promising enough that Bristol-
Myers plans to move directly into final-stage human trials in
lung cancer, melanoma, and kidney cancer, skipping the second of
three phases of drug development. The lung and kidney trials are
slated to start this year, and the melanoma trial by early 2013,
Sarah Koenig, a company spokeswoman, said.
'A Turning Point'
"After many years of negative studies, the idea of
reactivating the immune system against cancer seems to be paying
off," Roy Herbst, chief of medical oncology at the Yale Cancer
Center in New Haven, Connecticut, said by telephone. "It is a
turning point in the way we approach this disease."
It will take years of testing before researchers know for
sure whether the drugs, led by Bristol-Myers's product,
represents a real breakthrough or yet another hoped-for cancer
cure that fizzles in large trials.
Still, oncologists are particularly enthusiastic about the
potential of Bristol-Myers's drug to treat lung cancer, which
hits 226,000 Americans each year, killing about 160,000 of them,
according to the American Cancer Society.
Patients with advanced lung cancer who fail to respond to
chemotherapy often die within six to nine months. The potential
ability to produce "prolonged responses" that aren't seen with
other drugs makes it "the most exciting class of drugs right
now," said Scott Gettinger, a Yale Cancer Center lung cancer
specialist who is testing the drug. He wouldn't comment on the
updated data until it is presented at the cancer meeting.
Patient Response
David Gobin, a 62-year-old retired police officer from
Manchester, Maryland, who is one of the first patients to
undergo the treatment, is convinced the medicine is working for
him.
Gobin's lung cancer jumped into his liver and the space
around his lung despite his treatment with chemotherapy and
radiation, he said. Within two months after starting on the
Bristol-Myers therapy in February 2011, the tumors began to
shrink, and they remain dormant today, he said in a telephone
interview.
Gobin said he is breathing better, has gained back 20
pounds he had lost and next month plans to play golf again for
the first time in years.
"I've beaten the odds," Gobin said. "This is a miracle
drug for me."
Cellular Switch
Over the last decade, researchers have homed in on a
cellular switch, referred to as PD-1, that may be triggered by
cancer cells to help them evade destruction by the immune
system. Brahmer of Johns Hopkins refers to it as an
'invisibility cloak."
Bristol-Myers's drug is designed to work by binding to the
switch, blocking the ability of tumors to access it. The
medicine produced remission lasting a year or longer in a small
minority of patients who had failed on other therapies,
according to meeting abstracts released May 16.
Company executives won't comment further in advance of the
cancer meeting, Koenig said. At the oncology meeting,
researchers are expected to present updated data from the trial
examining how long the remissions from the anti-PD-1 drug last.
Cancer researchers have worked on therapies to trigger the
immune system against cancer for decades, with limited success
until recently. The field achieved a breakthrough in March 2011
with the approval of Bristol-Myers's Yervoy, the first drug
proven to extend the lives of advanced melanoma patients.
Yervoy, designed to blunt a different immune system off
switch, generated (BMY) $514 million in sales in its first 12 months.
Many Cancer Types
The PD-1 switch is linked to many tumors types and may
extend the success of cancer immune therapy. A key issue will be
whether the PD-1 drugs can stimulate the body against tumors
without causing dangerous autoimmune reactions.
One lung cancer patient in the Bristol-Myers drug trial
died from lung toxicity linked to the medicine, according to the
meeting abstracts.
While PD-1 was discovered two decades ago by Kyoto
University researcher Tasuku Honjo, it took years for
researchers to appreciate its role in cancer.
In one 2002 study, cancer researcher Lieping Chen, now at
Yale University, showed that numerous types of human tumors,
including cancers of the lungs, ovaries, colon, and melanoma,
have high levels of a protein that can trigger the PD-1 switch
on immune cells. This and similar data from other scientists
indicated tumors use PD-1 as a mechanism to evade the immune
system, Chen said.
Surprising Result
"It was a major surprise," Chen said in a telephone
interview.
The current thinking is that there is a war between the
immune system and cancer, said Gordon Freeman, a molecular
immunologist at Dana-Farber Cancer Institute in Boston.
While the body successfully wipes out many tumors at the
earliest stages years before they produce symptoms, eventually
"some of them escape and grow to become terrible things," he
said. Manipulating PD-1 is one of the ways the tumors may do
this, he said.
One of the first companies to focus on PD-1 was Princeton,
New Jersey-based Medarex Inc., which started developing a PD-1
antibody in 2005 with Ono Pharmaceutical Co. of Japan, and was
acquired by Bristol-Myers in 2009 for $2.4 billion. Ono has
rights to the PD-1 antibody drug in Japan, Korea, and Taiwan.
'Mop Up' Cancer
Among other competitors, Merck is presenting data at the
meeting showing that its PD-1-blocking drug helped shrink or
stabilize tumors in four of nine patients in an early trial. The
immune approach "ultimately may result in cures for metastatic
cancers that we have not been able to cure in the past," said
Gary Gilliland, a Merck senior vice president.
It may be especially effective when used after chemotherapy
to "mop up" remaining tumor cells and prevent the cancer from
recurring, he said.
Roche (ROG) is in the earliest stages of human testing on a drug
that works by a slightly different approach and may be more
effective, said Stuart Lutzker, a vice president at Roche's
Genentech unit. Instead of binding to immune cells, the Roche
drug acts inside tumors to block their ability to shut down
immune cells, he said.
Though Bristol-Myers has about a two-year lead on its
competitors, it's still too early to know which approach will
prove most effective, said Leerink Swann's Fernandez.
"It is going to be a race to the finish line," he said.
To contact the reporter on this story:
Robert Langreth in New York at
rlangreth@bloomberg.net
To contact the editor responsible for this story:
Reg Gale at
rgale5@bloomberg.net
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