FOSTER CITY, Calif. (AP) — Gilead Sciences Inc. said Tuesday its high blood pressure treatment candidate, darusentan, failed to meet the main goal of a late-stage clinical trial when compared to a placebo. A trial involving 849 patients did not show a statistically significant difference between darusentan and a placebo when measured for improvement in both systolic blood pressure — taken when the heart contracts — and in diastolic blood pressure — taken when the heart is filling with blood, Gilead said. Chief Scientific Officer Norbert Bischofberger said in a statement from the company the result was disappointing, and Gilead officials think it "would be challenging to define an expedient path forward." "We would likely be required to initiate another (late-stage) study and would rather allocate our resources to other promising research and development opportunities in our pipeline," he said. Darusentan is designed to improve treatment resistant hypertension, or high blood pressure that has not been successfully reduced by other drugs.