A trial of pertuzumab, trastuzumab and cyclophosphamide for older people with advanced breast cancer (EORTC 75111-10114)

The research team found that trastuzumab, pertuzumab and cyclophosphamide worked better for older people with advanced breast cancer. And that it didn’t cause too many side effects.

Trial design
The people taking part in this trial were aged 60 or more and had breast cancer that had spread. They all had breast cancer that was HER2 positive. This means their cancer cells made a protein called HER2.

Half had trastuzumab and pertuzumab. And half had trastuzumab, pertuzumab and cyclophosphamide tablets.

They had treatment until there were signs that their cancer had started to grow, or they had serious side effects. They could then have another treatment called trastuzumab emtansine (Kadcyla) if they wanted to.

Results
80 people took part in this trial. They were put into a treatment group at random:

• 39 had trastuzumab and pertuzumab
• 41 had trastuzumab, pertuzumab and cyclophosphamide

 
The research team looked at how long it was before people’s cancer started to grow. They found it was:

• 5.6 months for those who had trastuzumab and pertuzumab
• 12.7 months for those who had trastuzumab, pertuzumab and cyclophosphamide

They also assessed how well the treatment worked for most people who took part. They looked at how many people’s cancer got a bit smaller, or so small that it couldn’t be seen on a scan. They found it was:

• more than 4 out of 10 people (44%) who had trastuzumab and pertuzumab
• more than 5 out of 10 people (53%) who had trastuzumab, pertuzumab and cyclophosphamide

And the number of people living 1 year after joining the trial was:

• nearly 7 out of 10 (67%) who’d had trastuzumab and pertuzumab
• more than 8 out of 10 (84%) who’d had trastuzumab, pertuzumab and cyclophosphamide

Further treatment
29 people went on to have trastuzumab emtansine when their cancer started to grow again:

• 14 people who’d had trastuzumab and pertuzumab
• 15 people who’d had trastuzumab, pertuzumab and cyclophosphamide

The cancer got a bit smaller in 4 of these people, 2 in each group.

Quality of life
The people taking part filled out questionnaires before they started treatment and at 2 months, 6 months and 12 months. They were asked how they were feeling, and whether the treatment or its side effects had affected their day to day life.

The research team looked at the results of 29 people who completed all the questionnaires. 

They found that some people were less able to carry out day to day tasks, but this was similar in the two groups:

• 5 out of 11 people (45%) who’d had trastuzumab and pertuzumab
• 7 out of 18 people (39%) who’d had trastuzumab, pertuzumab and cyclophosphamide

Side effects
Most people taking part had at least one side effect. Many were mild or didn’t last long, but some people had more severe side effects:

• 9 out of 39 people (23%) who had trastuzumab and pertuzumab
• 18 out of 41 people (44%) who had trastuzumab, pertuzumab and cyclophosphamide

The most common of these side effects were increased blood pressure, diarrhoea, shortness of breath and extreme tiredness (fatigue). 

More people who had cyclophosphamide had a drop in blood clotting cells (platelets), white blood cells and red blood cells.

Conclusion
The trial team concluded that trastuzumab, pertuzumab and metronomic cyclophosphamide worked better for older people with advanced breast cancer. And that it didn’t cause too many side effects.

They suggest older people who have this combination may not need to have other chemotherapy drugs which could cause more side effects.

Where this information comes from    
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.