“I was keen to go on a clinical trial. I wanted to try new cancer treatments and hopefully help future generations.”
A trial using G-CSF to maintain the full dose of chemotherapy for people with breast cancer (SPROG)
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This trial was to find out if G-CSF could help people with early breast cancer continue to have the full dose of chemotherapy throughout treatment.
More about this trial
Breast cancer is often treated with chemotherapy. Some of the chemotherapy drugs used can cause a drop in the number of red blood cells, white blood cells and platelets (cells that help the blood to clot).
If there is a drop in the number of white blood cells, it means patients are at an increased risk of getting an infection. To try and prevent that happening, the next dose of chemotherapy is sometimes reduced. If the dose of chemotherapy has to be reduced or delayed, there is a concern that the treatment may be less effective.
G-CSF is a growth factor that stimulates white blood cells to grow. Giving G-CSF after each dose of chemotherapy may prevent the white blood cell count falling too far.
The aim of this trial was to give the full dose of chemotherapy and reduce the risk of infection.
Summary of results
The trial team found that more patients who had G-CSF were able to have most of their full dose of chemotherapy than those who didn’t have G-CSF.
This was a phase 3 trial. It recruited 407 people. Everyone had chemotherapy at planned doses and frequency for her breast cancer.
Their white blood cells were monitored. If the level dropped below a certain level or they got an infection and were admitted to hospital (a neutropenic event), they were put into 1 of 2 groups at
- 203 patients had the standard management of dose reduction
- 204 patients had G-CSF
The researchers were able to look at the results of 401 patients. The number of patients who were able to have most of their full dose (at least 85%) of chemotherapy was
- 100 patients (50%) in the standard management group
- 151 patients (75%) in the G-CSF group
This difference is extremely unlikely to have happened by chance so the researchers said it was
The team also looked at the number of people in each group that had further neutropenic events after being put into their group. They found that
- 65 out of every 100 people (65.7%) in the standard management group did
- 18 out of every 100 people (18.2%) in the G-CSF group did
The trial team concluded that significantly more patients who had G-CSF were able to have most of their full chemotherapy dose. This may have an important impact on how well they do after chemotherapy.
We have based this summary on information from the research team. The information they sent us has been reviewed by independent specialists (
How to join a clinical trial
Professor RCF Leonard
Anglo Celtic Cooperative Oncology Group
NIHR Clinical Research Network: Cancer