A trial of arsenic trioxide (Trisenox) for myelodysplastic syndromes

This trial was looking at arsenic trioxide (also called Trisenox) for myelodysplastic syndromes.

Myelodysplastic syndromes (MDS) are a group of diseases. In MDS too many blood cells are made by the bone marrow. Most of them are not normal and are destroyed before they get into the blood. This means the number of blood cells in the bloodstream is lower than normal. A drop in blood cells can cause an increased risk of infection, bleeding problems, tiredness and breathlessness. Depending on results of various tests, doctors classify MDS as being either high risk or low risk of turning into acute leukaemia.

If you have MDS but don’t have any symptoms, you may not have treatment straight away. But if you do have symptoms, you may have treatment with chemotherapy, or you may have supportive care. Supportive care means controlling the symptoms rather than treating the MDS itself. This includes treatments such as blood or platelet transfusions, antibiotics or injections of growth factors.

Arsenic Trioxide was a treatment that had been used for a type of leukaemia called acute promyelocytic leukaemia. Doctors thought it might also help people with MDS. The aims of the trial were to

• See how well arsenic trioxide worked for MDS

• Learn more about the side effects