A study of buparlisib and bortezomib for myeloma (BUBBLE)

Cancer type:

Blood cancers

Myeloma

Status:

Results

Phase:

Phase 1

This study looked at adding buparlisib to bortezomib for myeloma to improve treatment.

It was for people who:

had certain gene changes (mutations ) in their myeloma cells and
whose myeloma had come back or treatment had stopped working

This study was open for people to join between 2016 and 2017. The team reported the results in 2021.

More about this trial

Some people have gene changes in their myeloma cells. This means standard chemotherapy might not work as well. It also means the myeloma is more likely to come back or treatment might stop working.

When this study was done, doctors were looking for ways to improve treatment for this group of people. In this study, they looked at a drug called buparlisib.

Buparlisib is a type of targeted drug Open a glossary item called a cancer growth blocker. It works by blocking the action of proteins called PI3K.

Bortezomib was a standard treatment for myeloma at the time of the study. It is also a cancer growth blocker that works in a different way to buparlisib.

Researchers thought that adding buparlisib to bortezomib could improve treatment. They weren’t sure so wanted to find out more.

The main aims of the study were to:

find the best dose of buparlisib to have with bortezomib
see if this combination of treatment is safe
see how well treatment works
find out more about the side effects

Summary of results

The study team didn’t find the best dose of buparlisib to have with bortezomib. This was because the study closed earlier than planned.

Study design
This was a phase 1 study. The study was in 2 parts:

part 1 looked at the best dose of buparlisib to have with bortezomib
the plan was for part 2 to test this combination in people with the gene changes

Results
The study team had hoped to find 60 people to take part. Only 5 people joined the study:

3 people stopped treatment early because their myeloma got worse
1 person stopped treatment because of side effects
1 person decided not to go ahead with treatment

The study team had hoped to find the best dose to give. This wasn’t possible as the study closed early. This was because 2 trials looking at buparlisib for breast cancer showed it didn’t work very well. The company stopped making it so there wasn’t enough drug supply to continue with this study.

This also meant that part 2 of the study couldn’t go ahead.

Side effects
Everyone had side effects. Most of them were mild but a few were more severe.

The most common side effects of buparlisib and bortezomib were:

a drop in blood cells causing an increased risk of infection, tiredness and breathlessness (anaemia) and bleeding
diarrhoea

We have information about the side effects of bortezomib.

Conclusion
This study didn’t recruit enough people to find the best dose of buparlisib to have with bortezomib. For the few people who had treatment the side effects were manageable.

Where this information comes from
We have based this summary on information from the research team. As far as we are aware, the information they sent us has not been reviewed independently (peer reviewed) Open a glossary item or published in a medical journal yet. The figures we quote above were provided by the research team. We have not analysed the data ourselves.