A trial looking at vorinostat, bortezomib and dexamethasone for myeloma that has come back (MUK four)

This trial showed that adding vorinostat to bortezomib and dexamethasone worked for some people but the side effects were bad.

Results
16 people took part in this trial. The team had hoped to find more people to join but the trial closed earlier than planned. This was because it was difficult to recruit enough people. 

Everyone had vorinostat, bortezomib and dexamethasone for up to 6 months. This was their initial treatment. After initial treatment the team looked at how well treatment worked. They found the myeloma:

• went away completely in 4 people (a complete response)
• shrunk a lot in 2 people (a very good partial response)
• shrunk a bit in 7 people (a partial response)
• shrunk even less in 3 people (a minimal response)

11 people continued to have vorinostat on its own. This is called maintenance treatment. They had it for as long as it was working and the side effects weren’t too bad. 

The team also looked at how long before the myeloma started to grow again. They found this was 11.9 months. This is better than having standard treatment with bortezomib and dexamethasone. 

Side effects 
Most people taking part had at least 1 side effect. Some of these were mild or didn’t last long. But some were more severe.

The severe side effects of dexamethasone, bortezomib and vorinostat included:

• a drop in the number of blood cells called platelets
• diarrhoea
• tiredness (fatigue)
• a drop in the number of red blood cells (anaemia)

The team also looked at the side effects of vorinostat on its own. This was in the group of people who had maintenance treatment. The most common severe side effect was a drop in the number of blood cells called neutrophils .

They looked at the number of people who had side effects and had to:

• stop treatment
• reduce the dose of treatment 

They found this happened in 12 out of 16 people (75%).

Researchers can class a side effect as serious for a number of reasons, including if:

• the person has to go to hospital because of it
• it is particularly important for the specific treatment in the trial

4 people had serious side effects that were related to treatment. These included:

• heart palpitations 
• diarrhoea 
• sepsis  
• dehydration 
• a drop in blood pressure 

Everyone recovered from these serious side effects. 

Conclusion
This was a very small trial. The team concluded that adding vorinostat to bortezomib worked for some people in the trial but the side effects were bad. 

The team hope these results highlight that these types of drugs need to be improved. Further research could look at hopefully reducing the side effects and help to treat people with myeloma.

More detailed information
There is more information about this research in the references below. 

Please note, the information we link to here is not in plain English. It has been written for healthcare professionals and researchers.

Bortezomib, Vorinostat, and Dexamethasone Combination Therapy in Relapsed Myeloma: Results of the Phase 2 MUK four Trial
S Brown and others
Clinical Lymphoma, Myeloma & Leukemia, 2021. Volume 21, No 3, pages 154-161.

Where this information comes from
We have based this summary on the information in the article above. This has been reviewed by independent specialists (peer reviewed ) and published in a medical journal. We have not analysed the data ourselves. As far as we are aware, the link we list above is active and the article is free and available to view.