Drug shrinks ovarian tumours in early trial
A new targeted treatment for ovarian cancer has shown "very promising" results in women in the advanced stages of the disease.
It shrank tumours in about half of women who took part in a small trial.
Researchers
had only been testing the drug to see if it was safe for humans to
take, but found it had an almost instant clinical effect.
It is hoped the drug could help women who have stopped responding to all other currently available treatments.
So far, it has only been tested in 15 women, and the researchers say it may not be safe to take for more than a few months.
However, ovarian cancer is a difficult disease to treat, and the prognosis in the advanced stages is very poor.
Marianne
Heath, 68, one of the patients who received the drug, said: "I had no
other treatment choices, so I felt this was my only option.
"I
just want to keep going so I can keep the tumours at a level where I can
enjoy my life. It isn't a cure, but it is life extension for me."
Marianne
had treatment over six months, and the drug shrak all three tumours in
her body, taking away much of the pain she was experiencing.
One
tumour - in her back - has started growing again since she stopped the
treatment in January, and she is undergoing radiotherapy for that, but
the others are stable.
The
researchers, from the Institute of Cancer Research and the Royal
Marsden NHS Foundation Trust in London, wanted to establish whether the
drug, known in the study as ONX-0801, was safe, so they tested it on a
small number of patients.
But they found it significantly shrank tumours in seven of the 15 patients who took the drug - all seven carrying a particular molecule that the drug was specifically designed to target.
ONX-0801
is the first in a new class of drugs which work by mimicking the
ability of folic acid selectively to latch on to cancer cells, while
leaving healthy tissue alone, thus reducing the side-effects often seen
with traditional chemotherapy, such as infections, diarrhoea, nerve
damage and hair loss.
Once locked on to a cancer cell, the drug
disrupts its chemistry by blocking the action of a key molecule, causing
widespread DNA damage and cell death.
The researchers, who hope
to carry out bigger clinical trials as soon as possible, have also
developed a test that can detect which women are most likely to benefit
from the treatment.
Study leader Dr Udai Banerji said: "The
results we have seen in this trial are very promising. It is rare to see
such clear evidence of reproducible responses in these early stages of
drug development.
"The beauty of this particular drug is that it
is targeted to the cancer cell. This means there are fewer side-effects,
making it a kinder treatment for ovarian cancer patients.
"It's early days of course, but I'm keen to see this treatment assessed in later-stage clinical trials as soon as possible."
Dr
Catherine Pickworth, from Cancer Research UK, said: "It's encouraging
to see this new drug is showing promise as a potential new treatment for
ovarian cancer.
"The next steps will be for researchers to test
the drug in larger clinical trials to confirm it works and is safe, and
to work out which women with ovarian cancer this drug could help."
Prof Michel Coleman, of the London School of Hygiene & Tropical Medicine, urged caution.
He
said: "Shrinkage of tumours is important, but as the authors point out,
that is not the same as producing the hoped-for extension of survival
for women with ovarian cancer.
"The excitement of the
investigators is completely understandable, but one should be cautious
about interpreting this result as a breakthrough for ovarian cancer
patients until data on longer-term outcomes are available."
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