BACKGROUND: In October 2011, the National Institute for Health and Care Excellence (NICE) recommended the use of ticagrelor in adult patients presenting with acute coronary syndrome (ACS) in England and Wales. The relative effectiveness and cost-effectiveness of ticagrelor compared to clopidogrel—the current standard of care in the NHS—were based on results from one large multicentre study including over 18,000 ACS patients. Patients were recruited from October 2006 through to July 2008 and primary trial data analysis, published in September 2009, demonstrated that ticagrelor significantly reduced the rate of death, myocardial infarction (MI), and/or stroke versus clopidogrel. Delays in completing and reporting on RCTs can impede access to new valuable treatments; however, data simulation may allow for the continuous modelling of trial results and support early HTA submissions. OBJECTIVES: Using a data simulation approach to estimate the relative effectiveness of ticagrelor vs. clopidogrel from recruitment to final analysis, we explore whether a trial design with shorter follow-up or the publication of an interim analysis could have resulted in a positive NICE decision at an earlier time point. METHODS: Time-to-event data was extracted from published Kaplan-Meir curves and individual patient data was simulated assuming censoring and recruitment distributions. The relative effectiveness of ticagrelor was assessed as a continuum from 2006 to 2009; and the probability of ticagrelor being cost-effective in the UK was also evaluated over time using a trial-based economic model. RESULTS: Despite increased uncertainty around the probabilities of death, MI and stroke estimated from immature trial data; results suggest that ticagrelor was a cost-effective alternative to clopidogrel before the original completed 12 months follow-up. CONCLUSIONS: Data simulation allowed us to evaluate HTA outcomes prior to the original planned analysis which, in retrospect, could have led to an earlier NICE recommendation for ticagrelor in ACS.