Around 1 in 5 people diagnosed with cancer in the UK take part in a clinical trial.
A trial of niraparib for advanced cancer
More about this trial
PARP stands for poly ADP-ribose polymerase. It is a type of protein called an
The aims of this study were to
- Find the best dose of niraparib to give
- Find out how well it works for advanced cancers that have a change in genes called BRCA1 or BRCA2
Summary of results
The research team found the best dose of niraparib to give, and found it does have some effect on cancer cells.
This trial was in 2 parts, and recruited 100 people with advanced cancer in total.
Part A recruited 60 people who had, or were likely to have, a change (mutation) in their BRCA1 or BRCA2 gene. The people in this group had a number of different cancers.
Part B recruited an extra 40 people who didn’t have, or were unlikely to have, a change in their BRCA1 or BRCA2 gene. The people in this group had either ovarian cancer or prostate cancer that had not responded to treatment, or had come back.
The first few people who joined part A had the lowest dose of niraparib. As they didn’t have any serious side effects, the next few people had a higher dose. And so on, for 10 different doses. This is called a dose escalation study. The research team found that the highest dose caused some serious side effects, so they recommend the dose below that was the best one to use. The people joining part B all had this dose of niraparib
Niraparib did cause some side effects, but they were mostly mild or moderate. The most common side effects were
- A drop in blood cells which can cause an increased risk of infection, bleeding problems, tiredness and breathlessness
- Feeling or being sick
- Tiredness (fatigue)
The research team were able to look at how well the treatment worked for 77 of the people who took part. First they looked at the 51 people in part A who had a change in the BRCA1 or BRCA2 gene. They found that the cancer had
- Got smaller in 11 people (21%)
- Stayed the same in 36 people (71%)
- Continued to grow in 4 people (8%)
They also looked at 26 people in part B who didn’t have a change in the BRCA1 or BRCA2 gene. They found that the cancer had
- Got smaller in 3 people (11%)
- Stayed the same in 14 people (54%)
- Continued to grow in 9 people (35%)
The trial team concluded that niraparib didn’t cause too many side effects, and could be useful for people with or without changes in the BRCA1 or BRCA2 gene. They found the best dose to give, and recommend that this dose is used in future trials.
We have based this summary on information from the team who ran the trial. The information they sent us has been reviewed by independent specialists (
How to join a clinical trial
Professor Johann de Bono
Experimental Cancer Medicine Centre (ECMC)
Merck, Sharp & Dohme
The Royal Marsden NHS Foundation Trust