AstraZeneca has announced enrollment of the first patient in the new Gravity study (Gauging the lipid effects of RosuvAstatin plus ezetimibe Versus sImvastatin plus ezetimibe TherapY). Gravity is a clinical trial examining the impact on LDL-cholesterol ('bad' cholesterol) levels in patients with hypercholesterolaemia and coronary heart disease following a treatment regimen with lower doses of Crestor plus ezetimibe, compared to higher doses of simvastatin plus ezetimibe (in a fixed dose combination marketed as Vytorin or Inegy.

Ezetimibe is a cholesterol absorption inhibitor and this study is AstraZeneca's first head-to-head comparison of Crestor/ezetimibe with simvastatin/ezetimibe.

Crestor provides comprehensive dyslipidaemia management, offering the most effective LDL-C reduction of any statin available, with the additional benefit of raising HDL across the dose range.

In a previous clinical trial, Explorer, Crestor 40mg with ezetimibe 10mg helped high risk patients achieve unprecedented levels of LDL-C reduction of up to 70 per cent compared to 57 per cent with Crestor alone.

"Gravity will, for the first time, examine the effects of adding ezetimibe to low dose Crestor and to simvastatin in a head-to-head clinical trial setting, to see which of these treatment options achieves the greatest LDL-C lowering benefits. We expect these results to firmly establish Crestor as the best statin upon which to base any combination therapy for patients with dyslipidaemia," said Elisabeth Bjork, global medical science director for Crestor.

Gravity is a 12-week, open-label, randomised, parallel-group, multicentre, Phase IIIb study of 800 patients to compare the efficacy and safety of Crestor (rosuvastatin) 10mg and 20mg in combination with ezetimibe 10mg and simvastatin 40mg and 80mg in combination with ezetimibe 10mg in patients with hypercholesterolaemia and coronary heart disease (CHD) or a CHD risk equivalent, atherosclerosis or a 10-year CHD Risk of 20 per cent. Complete results are due in 2009.

Gravity is a part of AstraZeneca's extensive Galaxy clinical trials programme, designed to address important unanswered questions in statin research and to investigate the impact of Crestor on cardiovascular risk reduction and patient outcomes. Currently, more than 69,300 patients have been recruited from 55 countries worldwide to participate in the Galaxy Programme.

Crestor has now received regulatory approvals in over 90 countries across five continents. Over 11 million patients have been prescribed Crestor worldwide. Data from clinical trials and real world use shows that the safety profile for Crestor is in line with other marketed statins.