Last year in the UK over 60,000 cancer patients enrolled on clinical trials aimed at improving cancer treatments and making them available to all.
A trial looking at treosulfan to treat Ewing's sarcoma that has come back after treatment (OTIS)
This trial looked at treosulfan chemotherapy for children, young people and adults with Ewing’s sarcoma who already had treatment. The trial was supported by Cancer Research UK.
This trial was for both adults and children. We use the term 'you' in this summary, but if you are a parent, we are referring to your child.
More about this trial
Ewing’s sarcoma is a type of cancer that usually develops in, or near, the bones. It mainly affects teenagers, young adults and children.
Doctors usually treat Ewing’s sarcoma with chemotherapy. But if the tumour does not completely disappear, or continues to grow during chemotherapy, there are not many other treatments that doctors can use. So they are always looking for new ways to help people in this situation. In this trial, they looked at a drug called treosulfan.
Treosulfan is a chemotherapy drug similar to one that was already used to treat people with Ewing’s sarcoma. We know from research that treosulfan can help people with other types of cancer. The researchers thought that treosulfan may help people who had already had treatment for Ewing’s sarcoma.
The aims of this trial were to find out
• What effect treosulfan has on Ewing’s sarcoma
• What the side effects are
Summary of results
The trial team found that the dose of treosulfan they used didn’t help people with Ewing’s sarcoma.
This trial recruited 21 people and the team were able to look at the results of 20 people. They found that
- In 1 person, the sarcoma didn’t get any worse or any better (doctors call this stable disease)
- In 13 people, the sarcoma continued to grow
- 6 people stopped treatment because they became more sick. It was believed that this was due to the sarcoma continuing to grow, but these people were too unwell to have a
scanto confirm this.
The trial team looked at the average length of time that people were living without any sign of their cancer getting worse. They found this was just under 2 months. They also looked at the average length of time people lived overall and found this was just over 6 months.
The most common bad side effect of treosulfan was a drop in blood cells causing an increased risk of infection, bruising and bleeding.
The trial team concluded that this dose of treosulfan didn’t work for people who had already had treatment for Ewing’s sarcoma.
We have based this summary on information from the team who ran the trial. The information they sent us has been reviewed by independent specialists (
How to join a clinical trial
Please note: In order to join a trial you will need to discuss it with your doctor, unless otherwise specified.
Dr Maria Michelagnoli
Cancer Research UK
Experimental Cancer Medicine Centre (ECMC)
NIHR Clinical Research Network: Cancer
University College London (UCL)
The Adam Dealey Foundation
This is Cancer Research UK trial number CRUKE/09/013.