The trial team concluded that alemtuzumab worked for people who were MRD positive but it had significant side effects.
This was a phase 2 trial.
This main trial was open to people who had chemotherapy for their CLL and a blood test showed there were some leukaemia cells left (MRD positive).
In total, 47 people in took part in the main trial. Everyone started treatment with alemtuzumab. With 41 people receiving the full 6 weeks of treatment.
After treatment they had a bone marrow test and another blood test. The team looked at the results to see if there was any leukaemia cells left in the bone marrow or the blood. They found that:
- 39 people had no leukaemia cells - they were MRD negative
- 7 people had leukaemia cells – they were MRD positive
One person was too ill to have the bone marrow test or blood test.
The same tests were done 6 months after finishing treatment. Of the 39 people who were MRD negative immediately after treatment, 18 people were still MRD negative 6 months later. The average length of time these 18 people stayed MRD negative was just under 4 years.
Researchers noted that those who stayed MRD negative for more than 6 months after treatment appeared to have a greater chance of staying MRD negative.
The team looked at the total number of people who didn’t have any sign of their leukaemia 5 years after treatment. They found it was 25 people (53.2%).
They also looked at the total number of people who were alive after 5 years. They found it was 34 people (72.3%).
The most common reported side effects of alemtuzumab were:
- skin rash
- a drop in blood cells
- tiredness
- breathing problems
- high temperature (fever)
In addition, 15 people who were already MRD negative at the start of the trial were monitored alongside the main trial. It was found that the average length of time they stayed MRD negative, was similar to the people who were MRD negative at 6 months in the main trial.
The trial team concluded that this trial suggests that alemtuzumab can improve the outcome of people who were MRD positive after chemotherapy. But the side effects are bad. The team are now looking into another targeted cancer drug for people who are MRD positive after having chemotherapy. The drug is like alemtuzumab but with less severe side effects.
We have based this summary on information from the research team. The information they sent us has been reviewed by independent specialists (peer reviewed 
) and published in a medical journal. The figures we quote above were provided by the trial team who did the research. We have not analysed the data ourselves.
