From LONDON Daily Telegraph no comment from poster "Patients 'freefrom cancer' after immune-boost treatment"

Patients 'free from cancer' after immune-boost treatment

By Roger Highfield, Science Editor
Last Updated: 7:01pm BST 14/08/2008

Cancer patients have been left free of the disease after being treated
with a new drug which harnesses the power of their own immune cells.
# Cancer and immunotherapy Q and A
# Immunotherapy: could it be the cure for cancer?
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Four of 38 patients with non-Hodgkin's lymphoma have seen the disease
complete regressions following treatment, while five others saw
reductions of 50 per cent in their tumours.

Immunotherapy for cancer
While the trials were only carried out on patients with blood cancer,
it is hoped the methods can be adapted to tackle other cancers

The drug, which could prove cheaper than other therapies that try to
achieve the same effect with cells, works by activating the body's own
defences to attack the cancer.

The results have been described as an "exciting" and "significant"
development in the use of immunotherapy, the process of using the
body's own immune system to fight disease.

While the trials were only carried out on patients with the blood
cancer, it is hoped the methods can be adapated to tackle other
cancers.

The disease claims the lives of more than 150,000 people in the UK
every year and more than one million people are suffering from cancer
at any one time.
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Earlier this year doctors announced that a patient with advanced skin
cancer was free of the disease two years after they injected him with
billions of his own immune cells using a different method. However,
experts warned at the time that the process could prove extremely
expensive.

The development of the drug could prove a much cheaper alternative way
of providing immunotherapy treatments.

Professor Peter Johnson, Cancer Research UK's chief clinician, said:
"These exciting preliminary results come from using them to harness
the body's own immune response in a new way. Although the side effects
need to be monitored carefully, we hope that this type of treatment
will prove to be active in larger trials in the future"

"This a significant study," said Dr Cassian Yee, Fred Hutchinson
Cancer Research Center, Seattle, who has had significant results using
the alternative method of treating patients with white blood cells
grown in the lab.

"It remains to be seen if most of the responses are longlasting.
Certainly the results are very promising."

The drug, which has been developed by Micromet, in Bethesda, Maryland,
was trialled by a team led by Dr Ralf Bargou at University of Würzburg
in Würzburg, German.

The results, published in the journal Science, are encouraging because
they suggest that the bigger the dose, the bigger the effect.

Coauthor of the study Dr Patrick Baeuerle, of Micromet, said all seven
who received the highest dose responded to the drug.

"Two of the seven had a complete response, and five a partial
regression (greater than 50 per cent reduction of tumour).".

The longest duration of a response was so far seen in a patient who
received one quarter of their dose. After 13 months, he remains free
of the blood cancer.

There are adverse side effects involved, however, such as fevers and
chills, occasionally with confusion and tremor, though all stopped
after treatment ceased.

Now a further trial is investigating how the drugs works in patients
with another form of blood cancer, called acute lymphoblastic
leukaemia.

Trials with a similar drug are also under way on patients with another
type of cancer, which affects glandular tissue and can appear in the
lungs, prostate, breast, colon and elsewhere in the body.

Micromet targets the body's own white blood cells on the cancer, using
a fraction of a millionth of a gram of a specialised protein called a
"bispecific antibody".

The company has created antibodies, called BiTE antibodies, which are
able to stick to sites with exquisite precision, in this case to
activate specialised white blood cells ( T cells) to attack cancer and
the results published today in the journal Science are encouraging
because the bigger the dose, the bigger the effect.

The antibodies overcome a key problem with immunotherapy that as
tumours become more advanced they become more "invisible" to the T
cells because the cancer cells lack molecules for white blood cells to
hang on to and stage their attack.

Normal antibodies are designed to latch on to one molecular target but
the bispecific antibody developed by Micromet, given the name
blinatumomab, binds to two, the cancer cell and the T cell, and bring
the two together to target the immune system on the cancer.

The team tried varying doses of blinatumomab in patients, and found
that among 38 patients, at doses from 0.0005 to 0.06 milligrams
(millionths of a gram) per square metre of body surface per day, 11 of
them exhibited major responses and tumour shrinking. The disease was
cleared from bone marrow, spleen and liver too.