BACKGROUND: The complexity of treatment regimens, costs and pill burden decrease 
the medication adherence and contribute to shortfall in cardiovascular 
preventive drug coverage. The polypill, a fixed dose combination pill of 
established drugs, is expected to increase adherence and reduce the costs whilst 
preventing major cardiovascular events (MCVE).
DESIGN AND METHODS: The PolyIran trial is a pragmatic cluster randomized trial 
nested within the Golestan Cohort Study (GCS). Subjects were randomized to 
either non-pharmacological preventive interventions alone (minimal care arm) or 
together with a polypill (polypill arm) comprising hydrochlorothiazide, aspirin, 
atorvastatin and either enalapril or valsartan. This study benefits from the 
infrastructure of the primary health care system in Iran and the interventions 
are delivered by the local auxiliary health workers (Behvarz) to the 
participants. The primary outcome of the study is the occurrence of first MCVE 
within five years defined as non-fatal and fatal myocardial infarction, unstable 
angina, sudden death, heart failure, coronary artery revascularization 
procedures, and non-fatal and fatal stroke.
TRIAL STATUS: From February 2011 to April 2013, 8410 individuals (236 clusters) 
attended the eligibility assessment. Of those, 3421 in the polypill arm and 3417 
in the minimal care arm were eligible. The study is ongoing.
CONCLUSION: The infrastructure of GCS and the primary health care system in Iran 
enabled the conduct of this pragmatic large-scale trial. If the polypill 
strategy proves effective, it may be implemented to prevent cardiovascular 
disease in developing countries.