The aim of this trial is to find out if a tablet called apixaban can reduce blood clots in people with lung cancer having chemotherapy or similar treatments. Apixaban is a type of oral anticoagulant ("blood thinner") that makes the blood less sticky to prevent blood clots forming.
The trial is trying to find out if apixaban it can reduce blood clots in people with lung cancer.
Participants will receive the following treatment:
• Apixaban or placebo, 2.5mg taken by mouth twice a day for 6 months. This treatment will be taken in addition to any treatment that they are receiving to treat their lung cancer.
Participants will need to:
* Sign a consent form to enter the trial.
* Take the trial treatment as directed by the research team
* Complete a participant diary to record when they took the trial treatment
* Complete the Quality of Life and Health resource use questionnaires.
* Female participants of childbearing potential must use adequate contraception during the trial and for at least 2 days after trial treatment has finished.