U-TXM study
The thromboxane biosynthesis study was undertaken at 28 UK centres. Participants provided 6-ml urine samples at trial entry/baseline (off aspirin), after the 8-week run-in period of aspirin 100 mg daily (24 h after the previous aspirin dose), and a third sample between 3 and 6 months after randomisation to blinded treatment (aspirin 100 mg, aspirin 300 mg or matched placebo) (Fig. 