for people ages 12-65 (full criteria)
at Sacramento, California and other locations
study started
estimated completion



This clinical trial is a Phase 2/3 study that will evaluate the efficacy and safety of FT-4202 and test how well FT-4202 works compared to placebo to improve the amount of hemoglobin in the blood and to reduce the number of vaso-occlusive crises (times when the blood vessels become blocked and cause pain).

Official Title

An Adaptive, Randomized, Placebo-controlled, Double-blind, Multi-center Study of Oral FT-4202, a Pyruvate Kinase Activator in Patients With Sickle Cell Disease (HIBISCUS)


FT-4202 is designed to activate PKR and thereby modulate RBC metabolism by impacting two critical pathways in RBCs. The FT-4202 clinical development program will investigate whether decreasing 2,3-DPG may help oxygen bind to hemoglobin (i.e. increasing oxygen affinity), and thereby increase ATP and impact RBC function. This study is a randomized, placebo-controlled, double-blind, multicenter Phase 2/3 study of patients age 12 to 65 years (inclusive), with sickle cell disease. There are two planned interim analyses in this study design. Initially, patients will be randomized at 1:1:1 to one of two dose levels of FT-4202 or placebo. At the first interim analysis, one of the two FT-4202 dose levels will be selected for the Phase 3 portion of the study, in which patients will be randomized at 1:1 to the selected FT-4202 dose or placebo. Efficacy on hemoglobin will be evaluated at the second interim analysis, and then will be tested along with evaluation of efficacy on vaso-occlusive crises at the final analysis. Following completion of 52 weeks of double-blind treatment, patients may enter a 52-week FT-4202 open-label extension period.


Sickle Cell Disease Sickle Cell Anemia Sickle Cell Anemia Hemolytic Hemoglobin Vaso-occlusive Crisis Sickle Cell Crisis Congenital Anemia Hemolytic Anemia Hematologic Disease Hemoglobinopathies Genetic Disease Inborn Disease Sickle Cell Trait Pyruvate Kinase Anemia, Sickle Cell FT-4202 Tablets Open label FT-4202


You can join if…

Open to people ages 12-65

  • Provision of consent
  • Patient has a confirmed diagnosis of sickle cell disease
  • At least 2 episodes of vaso-occlusive crises in the past 12 months
  • Hemoglobin ≥ 5.5 and ≤ 10 g/dL (≥ 55 and ≤ 100 g/L) during screening
  • Patients taking hydroxyurea, must demonstrate a stable dose for at least 90 days prior to start of study treatment
  • Female patients of childbearing potential must use highly effective methods of contraception, male patients are willing to use barrier methods of contraception

You CAN'T join if...

Medical Conditions

  • More than 10 vaso-occlusive crises within the past 12 months
  • Female who is breast feeding or pregnant
  • Hepatic dysfunction characterized by:
  • Alanine aminotransferase (ALT) > 4.0 × upper limit of normal (ULN)
  • Direct bilirubin > 3.0 × ULN
  • Known HIV positive
  • Active hepatitis B or hepatitis C infection
  • Severe renal dysfunction or on chronic dialysis
  • History of unstable or deteriorating cardiac or pulmonary disease within 6 months prior to consent including but not limited to the following:
  • Unstable angina pectoris or myocardial infarction or elective coronary intervention
  • Congestive heart failure requiring hospitalization
  • Uncontrolled clinically significant arrhythmias
  • Symptomatic pulmonary hypertension
  • History of overt clinical stroke within previous 2 years or any history of an intracranial hemorrhage

Prior/Concomitant Therapy

  • Patients receiving regularly scheduled blood (RBC) transfusion therapy (also termed chronic, prophylactic, or preventive transfusion)
  • Receiving or use of concomitant medications that are strong inducers or moderate/strong inhibitors of CYP3A4/5 within 2 weeks of starting study treatment or anticipated need for such agents during the study
  • Use of voxelotor within 28 days prior to starting study treatment or anticipated need for this agent during the study
  • Use of a selectin antagonist (eg, crizanlizumab or other monoclonal antibody or small molecule) within 28 days of starting study treatment or anticipated need for such agents during the study
  • Use of erythropoietin or other hematopoietic growth factor treatment within 28 days of starting study treatment or anticipated need for such agents during the study
  • Receipt of prior cellular-based therapy (eg, hematopoietic cell transplant, gene modification therapy)


  • UC Davis Medical Center - UC Davis Comprehensive Cancer Center - Hemotology/Oncology Clinic accepting new patients
    Sacramento California 95817 United States
  • Pacific Research Partners, LLC accepting new patients
    Oakland California 94607 United States


accepting new patients
Start Date
Completion Date
Forma Therapeutics, Inc.
Sign up for this study
Phase 2/3
Study Type
Last Updated