A trial of AT13148 for advanced solid tumours

The trial team found the best dose of AT13148 to give. In a very few people, the cancer stayed the same. But AT13148 treatment didn’t shrink the cancer in anyone who took part. 

This trial was open for people to join between 2012 and 2017. Researchers reported the results in 2018.

About this trial
This phase 1 trial took place in the UK. 56 people with advanced solid tumours took part. There were 27 people with advanced bowel cancer. 29 had other types of cancer. Some of these included:

• breast
• pancreas
• bile duct
• eye
• lung
• ovary
• kidney 
• skin 

51 people had treatment. They had at least 1 dose of AT13148.

AT13148 is a capsule. People had this capsule 3 times a week. The first few people taking part had a low dose of AT13148. If they didn’t have any serious side effects, the next people had a higher dose. And so on, until the researchers found the best dose to give. This is called a dose escalation study. 

People could have treatment for up to a year if it was working and the side effects weren’t too bad. But nobody had treatment for this long. 

Results
Researchers looked at the results of the dose escalation study. They found the best dose of AT13148 was 180mg. 14 people had this dose. There were too many side effects at the two highest doses that people had (240 mg and 300 mg). So, a lower dose of 180 mg was chosen as the best dose.

Researchers looked at how well AT13148 worked. To do this they measured the tumours with scans at the beginning of the trial and every 2 months. They included 18 people in this analysis. They found:

• in 3 people the cancer stayed the same (stable disease )
• in 15 people the cancer got worse 

AT13148 treatment didn’t shrink the cancer in anyone who took part. 

Samples
The trial team took blood samples. They looked at what happened to AT13148 in the body. Five people had the highest dose of the drug. This was 300 mg. At this dose, lab tests showed that the drug worked as expected. But due to the side effects, it wasn’t a suitable dose to give to more people. 

At the doses lower than 300 mg it wasn’t possible to block the cancer signals that the cancer used to divide and grow. 

Low blood pressure was a common side effect. The researchers looked at tumour samples that some people gave. The results showed that the drug affected how the body regulated blood pressure. They didn’t know about this when they started the trial. 

Side effects
36 out of 51 people who had AT13148 reported side effects. The most common were:

• low blood pressure
• feeling sick
• headache
• tiredness

Other side effects included: 

• loss of appetite
• diarrhoea
• being sick

10 people had serious side effects. These included: 

• low blood pressure
• liver problems
• a decrease in a type of white blood cell called neutrophils
• rash
• breathlessness
• tiredness
• low oxygen in the blood
• lung inflammation (pneumonitis)
• feeling sick
• kidney problems

Conclusion
The trial team found the best dose of AT13148 to give. But it didn’t help to shrink the tumours in anyone who had treatment in this trial. 

The trial has helped researchers learn more about: 

• the side effects of AT13148 
• how AT13148 works
• how it affects the body and what the body does to the drug

At the moment, the trial team are not planning to look at AT13148 in more trials.

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 ) 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.