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).



Eligible Ages
Between 12 Years and 65 Years
Eligible Genders
Accepts Healthy Volunteers

Inclusion Criteria

  • 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

Exclusion Criteria

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)

Study Design

Phase 2/Phase 3
Study Type
Intervention Model
Parallel Assignment
Primary Purpose
Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)

Arm Groups

ArmDescriptionAssigned Intervention
Double blind FT-4202 Low Dose
  • Drug: FT-4202 Tablets
    200 mg once daily
Double blind FT-4202 High Dose
  • Drug: FT-4202 Tablets
    400 mg once daily
Double Blind Placebo
  • Drug: Placebo Tablets
    Placebo once daily
Open label FT-4202
  • Drug: FT-4202 Tablets
    Selected dose once daily

Recruiting Locations

Boston Medical Center
Boston, Massachusetts 02118
Elizabeth Pottier

More Details

Forma Therapeutics, Inc.

Study Contact

Forma Therapeutics, Inc.

Detailed Description

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.


Study information shown on this site is derived from ClinicalTrials.gov (a public registry operated by the National Institutes of Health). The listing of studies provided is not certain to be all studies for which you might be eligible. Furthermore, study eligibility requirements can be difficult to understand and may change over time, so it is wise to speak with your medical care provider and individual research study teams when making decisions related to participation.