A notice for Participants being randomised in Add-Aspirin from 1st April 2023

The Add-Aspirin trial has been studying 2 different doses of aspirin (100mg and 300mg) versus placebo (a dummy tablet) and participants taking part in the trial to date have been randomly assigned one of these two doses or a placebo to take daily for 5 years. The company which manufactures the aspirin used in the trial (Bayer Pharmaceuticals) have recently announced that they will stop producing 300mg aspirin after the end of March 2023. This means that on or after 1st April 2023, new participants joining the trial will receive either 100mg aspirin or placebo only. For every 3 participants randomised to the trial, 2 will receive 100mg aspirin and 1 will receive placebo (which means the chance of being randomised to aspirin remains the same).

The aspirin produced by Bayer has a 5-year shelf life, meaning their last batch of 300mg aspirin will be used until the end of March 2028. Therefore, participants already taking part in the trial will continue on the treatment they were allocated to receive when they joined the trial. This change is an operational decision following the drug manufacturer’s announcement and has no impact on patient safety or the integrity of the trial. The trial oversight committees who monitor the conduct of the trial have approved this change.

The Add-Aspirin team would like to thank you for your continued participation in the Add-Aspirin study.