“I was keen to go on a clinical trial. I wanted to try new cancer treatments and hopefully help future generations.”
A trial looking at zoledronic acid for breast cancer that has spread to the bones (BISMARK)
This trial compared different ways of giving zoledronic acid for breast cancer that has spread to the bones. This trial was supported by Cancer Research UK.
When cancer spreads to the bone it can make the bone weaker and cause pain. Drugs called bisphosphonates can slow down the damage and reduce pain. Zoledronic acid (Zometa or zoledronate) is a bisphosphonate.
Doctors often prescribe zoledronic acid through a drip into a vein, once every 3 to 4 weeks. This is the standard treatment (S-ZOL) used in this trial. But they wanted to find out if it’s better to use a urine test to decide how often to give zoledronic acid. The test measures the level of a
This trial compared S-ZOL and M-ZOL. The aim was to find out if using bone marker directed treatment worked as well as standard treatment for reducing bone pain and weakness.
Summary of results
The research team found that using bone marker directed treatment wasn’t better than the using standard treatment.
This trial recruited slower than hoped, and closed earlier than expected having recruited just 289 people with advanced breast cancer. Of these
- 146 had standard zoledronic acid treatment (S-ZOL) once every 3 to 4 weeks
- 143 had marker directed zoledronic acid treatment (M-ZOL)
How often people in the M-ZOL group had treatment depended on the level of NTX marker in their urine. It ranged from every 3 or 4 weeks, to every 15 or 16 weeks.
The research team looked at how many people developed problems with their bones that required medical attention. These are called skeletal related events (SRE) and include
- A fractured or broken bone
- Radiotherapy to the bone
- Surgery to the bone
- Pressure on your spinal cord from the cancer (spinal cord compression)
They found that just over 3 out of 10 people (32%) who had standard treatment had at least one SRE, compared to nearly 4 out of 10 (38%) who had marker directed treatment. These results are similar, but they found that more people who’d had marker directed treatment had 2 or more SREs.
It is difficult to draw firm conclusions from this trial because it didn’t recruit as many patients as hoped. But the research team conclude that using markers to decide how often to give zoledronic acid is not as good as standard treatment every 3 to 4 weeks.
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 Robert Coleman
Cancer Research UK
Experimental Cancer Medicine Centre (ECMC)
National Institute for Health Research Cancer Research Network (NCRN)
University of Leeds
University of Sheffield
This is Cancer Research UK trial number CRUK/05/18.