About the Hibiscus Study™

The Hibiscus Study is evaluating the safety and effectiveness of an investigational medication on treating anemia and reducing the number of annual sickle cell crises in people 12 to 65 years of age with sickle cell disease (SCD).

Who may qualify

Eligible participants must:

  • Be 12 to 65 years of age (inclusive).
  • Have a confirmed diagnosis of SCD.
  • Have had at least 2 pain episodes (vaso-occlusive crises) within the past 12 months.
  • Have had no more than 10 pain episodes within the past 12 months.
  • Be willing and able to follow all study requirements and study visit schedules.
  • Be willing and able to take the assigned study treatment, which is 2 tablets, once a day.

There are additional eligibility requirements, which the investigator will explain to you.

Study participation

Participation in this study will last up to 113 weeks, which is just over 2 years, and will require up to 25 visits throughout the course of the study. This includes:

  • Screening: This period lasts up to 5 weeks. During this time, the study team will confirm if the study is a good match for interested individuals.
  • Double-blind treatment: This period lasts up to 52 weeks. “Double-blind” means neither the participant nor the study team will know if the participant has been assigned the investigational medication or the placebo.
  • Open-label extension treatment: This period lasts up to 52 weeks. “Open-label” means the participant and the study team will know which treatment option has been assigned. All participants will receive the investigational medication in this period. If you are eligible for this period, you will need to sign a separate informed consent form to take part.
  • End-of-study visit: This visit happens approximately 4 weeks after the last full dose of the investigational medication or placebo. This visit is important because the study team will check on participants’ health after stopping the study treatment.

Throughout the study, the investigator may perform a number of tests and procedures, including but not limited to:

  • A physical exam.
  • An electrocardiogram (ECG).
  • A pregnancy test (if applicable).
  • Collection of blood and urine samples.