UNITED STATE APPROVES BREAKTHROUGH LEUKAEMIA TREATMENT THAT 'EMPOWER' BLOOD CELLS TO ATTACK CANCER
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approved a breakthrough treatment that genetically
engineers patients' own blood cells into an army of
assassins to seek and destroy childhood leukaemia .
The Food and Drug Administration called the approval
historic, the first gene therapy to hit the US market. Made
from scratch for every patient, it's one of a wave of “living
drugs” under development to fight additional blood
cancers and other tumours, too.
Novartis Pharmaceuticals set the price for its one-time
infusion of so-called “CAR-T cells” at $475,000, but said
there would be no charge for patients who didn't show a
response within a month.
“This is a brand new way of treating cancer,” said
Dr Stephan Grupp of Children's Hospital of Philadelphia,
who treated the first child with CAR-T cell therapy — a girl
who'd been near death but now is cancer-free for five
years and counting. “That's enormously exciting.”
CAR-T treatment uses gene therapy techniques not to fix
disease-causing genes but to turbocharge T cells, immune
system soldiers that cancer too often can evade.
Researchers filter those cells from a patient's blood,
reprogramme them to harbour a “chimeric antigen
receptor” or CAR that zeroes in on cancer, and grow
hundreds of millions of copies. Returned to the patient,
the revved-up cells can continue multiplying to fight
disease for months or years.
It's a completely different way to harness the immune
system than popular immunotherapy drugs called
“checkpoint inhibitors” that treat a variety of cancers by
helping the body's natural T cells better spot tumours.
CAR-T cell therapy gives patients stronger T cells to do
that job.
“We're entering a new frontier in medical innovation with
the ability to reprogramme a patient's own cells to attack
a deadly cancer,” said FDA Commissioner Scott Gottlieb.
The first CAR-T version, developed by Novartis and the
University of Pennsylvania, is approved for use by several
hundred patients a year who are desperately ill with acute
lymphoblastic leukaemia, or ALL. It strikes more than
3,000 children and young adults in the U.S. each year and
while most survive, about 15 percent relapse despite
today's best treatments.
In a key study of 63 advanced patients, 83 percent went
into remission soon after receiving the CAR-T cells.
Importantly, it's not clear how long that benefit lasts:
Some patients did relapse months later. The others still
are being tracked to see how they fare long-term.
Still, “a far higher percentage of patients go into remission
with this therapy than anything else we've seen to date
with relapsed leukaemia,” said Dr. Ted Laetsch of the
University of Texas Southwestern Medical Center, one of
the study sites. “I wouldn't say we know for sure how
many will be cured yet by this therapy. There certainly is a
hope” that some will be.
Most patients suffered side effects that can be gruelling,
even life-threatening. An immune overreaction called
“cytokine release syndrome” can trigger high fevers,
plummeting blood pressure and in severe cases organ
damage, side effects that require sophisticated care to
help patients without blocking the cancer attack. The FDA
designated a treatment for those side effects Wednesday.
“This is remarkable technology,” said Dr Mikkael Sekeres
of the American Society of Haematology. But, he
cautioned that CAR-T “isn't a panacea.”
Among concerns, sometimes leukaemia can develop
resistance, and sometimes patients worsen while waiting
for their new cells, said Sekeres, who directs the
Cleveland Clinic's leukaemia programme and wasn't
involved with CAR-T testing.
“Unfortunately leukaemia grows so rapidly that it can
evade even the smartest of our technologies,” he added.
To better ensure patient safety, the FDA is requiring
Novartis to offer CAR-T therapy only through medical
centers specially trained and certified to handle the
complicated treatment. Novartis expects to have 32
centres around the country, mostly in large cities, running
by year's end, with the first 20 offering care within the next
month.
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