'Living drug' offers hope to terminal blood cancer patients
'Living drug' offers hope to terminal blood cancer patients
21 June 2019
Mike Simpson, 62, from Durham,
says his cancer is now "on the run".
The therapy, called CAR-T, is a
"living drug" that is tailor-made for each patient using their body's
own cells
Doctors at King's College
Hospital, London, said some patients were being completely cured in a way that
had "never been seen before".
How does the treatment work?
CAR-T is the pinnacle of personalised
medicine as it has to be developed for each individual patient.
Firstly, parts of the immune
system - specifically white blood cells called T-cells - are removed from the
patient's blood.
They are frozen in liquid
nitrogen and sent to laboratories in the United States.
There, the white blood cells are
genetically reprogrammed so that rather than killing bacteria and viruses, they
will seek out and destroy cancer.
They are now "chimeric
antigen receptor T-cells" - or CAR-T cells.
Millions of the modified cells are grown in the lab,
before being shipped back to the UK where they are infused into the patient's
bloodstream.
The whole manufacturing process
takes a month.
As this is a "living
drug", the cancer-killing T-cells stay in the body for a long time and
will continue to grow and work inside the patient.
Who is benefiting?
Mike Simpson was one of the first
NHS patients to be treated.
He was diagnosed with large
B-cell lymphoma - a type of blood cancer - in 2015 when he returned from a
holiday with a stiff and swollen neck.
Two bouts of chemotherapy
initially controlled his cancer, but each time it returned.
By the end of 2018, he was given
less than two, unpleasant and probably painful, years to live.
"If this treatment wasn't
offered to me, I'd be saying goodbye in a relatively short period of
time," he told the BBC.
He started the treatment in
February and follow-up scans show the CAR-T therapy is working.
He added: "I feel the
treatment really is being effective, that we've got the cancer pretty much on
the run.
"Obviously I'm really happy
about that and optimistic for the future and glad that I committed to the
treatment."
However, it is still too soon to
know whether the therapy has been completely successful.
Up to 200 patients a year like
Mike could benefit from the therapy.
How effective is it?
This is a new therapy and very
long-term data is still lacking.
Clinical trials have shown that 40% of
patients had all signs of their otherwise untreatable, terminal lymphoma
eliminated from their body 15 months after treatment.
"It is a very exciting new
development and it gives new hope to a lot of our patients," Victoria
Potter, consultant haematologist at King's College Hospital told the BBC.
She added: "It's amazing to
be able to see these people, who you may have not been able to give any hope
to, actually achieving remission.
"And that is a situation we
have never seen before and it's an incredibly impressive change in the
treatment paradigm."
Is it safe?
Mike says the side-effects of his
treatment were worse than either of his two batches of chemotherapy.
Short-term neurotoxicity, where
the brain and nerves are affected, can lead to confusion, difficultly speaking
and a loss of consciousness.
There are five days after the
treatment, when Mike was on intensive care, that he cannot remember at all.
"It might be a magic bullet,
but it hurts," said Mike.
His brain function is back to
normal, but Mike says fatigue means he's not ready to go back to work.
How much does this cost?
This truly personalised medicine
- made from and for each individual patient - is unsurprisingly expensive.
The official list price for this
CAR-T therapy, called Yescarta, is more than £280,000 per patient.
A deal has been struck between
NHS England and the pharmaceutical company Gilead Sciences, but how much this
is costing remains confidential.
Simon Stevens, chief executive of
NHS England, said: "CAR-T shows huge promise and it is fantastic to see
that patients in the NHS are among the first in the world to benefit.
"The start of this treatment
marks the beginning of a new era of personalised medicine."
Does it work for other cancers?
CAR-T has so far shown the most
promise in blood cancers including types of lymphoma and leukaemia.
The first NHS patient to receive it was 11-year-old
Yuvan Thakkar, who has a form of leukaemia.
"Solid cancers" - those
that form tumours like lung cancer or melanoma - have been more challenging.
One reason the blood cancer work has been easier is
down to acceptable collateral damage.
CAR-T cells have to target
proteins that stick out from the surface of a cancerous cell.
Cancerous B-cells (a type of
immune cell in the blood) have a protein called CD19 on the outside, but so too
do healthy B cells.
So CAR-T therapies that currently
target CD19 are wiping out healthy and cancerous cells.
This is an acceptable amount of
collateral damage as the rest of the immune system is still there and drugs can
help plug the gap.
The same is not true in other
cancers - you cannot destroy the lungs to kill lung cancer, or the skin to kill
melanoma.
So more precise targets are being
developed and are entering clinical trials.
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