DORADO-AC-EX – A Long-Term Safety Extension Study to the Phase 3 DORADOC-AC Study (Protocol DAR-312) of Darusentan in Resistant Hypertension


This is a double-blind, active-controlled, long-term study of a new experimental drug called darusentan. Darusentan in not currently approved by the United States Food and Drug Administration (FDA), which means that a doctor cannot prescribe this drug. The purpose of this study is to evaluate the long-term safety of darusentan (optimized dose) as compared to an active control, administered orally.

Full Title of Study: “A Double-Blind, Active-Controlled, Long-Term Safety Extension Study of Optimized Doses of Darusentan in Subjects With Resistant Hypertension Despite Receiving Combination Therapy With Three or More Antihypertensive Drugs, Including a Diuretic, as Compared to Guanfacine (Protocol DAR-312-E)”

Study Type

  • Study Type: Interventional
  • Study Design
    • Allocation: Randomized
    • Intervention Model: Parallel Assignment
    • Primary Purpose: Treatment
    • Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
  • Study Primary Completion Date: February 2010


  • Drug: Darusentan
    • Darusentan capsules at a dose of 50, 100, or 300 mg administered orally once daily
  • Drug: Guanfacine
    • Guanfacine 1 mg capsules administered orally once daily

Arms, Groups and Cohorts

  • Experimental: Darusentan
    • Darusentan capsules titrated to an optimal dose of 50 mg, 100 mg, or 300 mg administered orally once daily
  • Active Comparator: Guanfacine
    • Guanfacine 1 mg capsules administered orally once daily

Clinical Trial Outcome Measures

Primary Measures

  • Change from baseline in mean 24-hour systolic and diastolic ambulatory blood pressure
    • Time Frame: Baseline to Week 14
  • Percentage of subjects who reach systolic blood pressure goal
    • Time Frame: Week 14
  • Change from baseline in estimated glomerular filtration rate (eGFR)
    • Time Frame: Baseline to Week 14

Secondary Measures

  • Change from baseline in trough sitting systolic and diastolic blood pressures
    • Time Frame: Baseline to Week 14

Participating in This Clinical Trial


1. Subjects must be competent to provide written informed consent; 2. Subjects must have completed the Maintenance Period of the DAR-312 study. SELECTED EXCLUSION CRITERIA:

1. Subjects who discontinue treatment with study drug prior to the end of the Maintenance Period in DAR-312 due to a study drug-related AE; 2. Subjects who experience a study drug-related serious adverse event (SAE) during the DAR-312 study.

Gender Eligibility: All

Minimum Age: 35 Years

Maximum Age: 80 Years

Are Healthy Volunteers Accepted: No

Investigator Details

  • Lead Sponsor
    • Gilead Sciences
  • Provider of Information About this Clinical Study
    • Sponsor

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