The Prostate cancer – Exercise and Metformin Trial (Pre-EMpT) was a trial involving men diagnosed with prostate cancer. It aimed to find out how practical or feasible it would be to ask those men to increase their activity levels or take metformin (a medication for type 2 diabetes).
This was because previous studies had shown that men with prostate cancer can reduce their risk of cancer progression or cancer-specific death by taking part in moderately intense physical activity. Other studies had also shown that men taking metformin have a reduced risk of prostate cancer and prostate cancer-specific death.
We wanted to assess how many men, who were eligible, would agree to take part in the study. We also wanted to assess whether men continued to exercise and/or take metformin six months after they started taking part in it.
This feasibility study used a factorial design. This meant we could estimate the effects of each factor (physical activity and/or metformin supplementation). We assigned men with prostate cancer to one of four groups:
- physical activity
- metformin supplementation
- combined physical activity and metformin supplementation
- control group (no change to normal routine)
Men in the physical activity group walked briskly for 30 or more minutes a day. We asked them to do this at least five days a week with an additional goal of walking 10,000 steps a day. Men in the metformin supplementation group took a 500mg metformin tablet once a day.
We followed up with the men in our study at 3, 6 and 12 months after they started taking part in the trial. We measured step counts (pedometer, physical activity monitor) and tablet counts. We used questionnaires (including prostate cancer-related symptoms) and took blood samples.
We have now finished collecting data and are writing our findings up for publication. We will use the findings and insights from this trial, including qualitative research, to inform the design of a phase 2 trial of the metformin and physical activity interventions.
We are also planning a trial of physical activity in men of South Asian origin who tend to get help from health services when their prostate cancer is more advanced. They are also at higher risk of experiencing the negative metabolic effects of treatment with androgen deprivation therapy (a therapy aimed at reducing levels of male hormones in the body). This trial will be in collaboration with the Bradford Institute for Health Research.