A Phase 2, Open-Label Study to Assess the Pharmacokinetics, Pharmacodynamics and Safety of Orally Administered Epeleuton in Patients with Sickle Cell Disease

Background.

Sickle cell disease (SCD) is a rare hereditary multi-system disorder that is caused by a single mutation in the beta allele of the hemoglobin gene, leading to the production of sickle hemoglobin (HbS). HbS polymerizes when deoxygenated, resulting in red blood cell (RBC) sickling and membrane damage, ultimately leading to a cascade of events which include hemolysis, chronic anemia, inflammation, and vaso-occlusion. Despite recent progress, there is a need for additional disease-modifying therapeutic options.

Epeleuton is 15-hydroxy eicosapentaenoic acid (15(S)-HEPE) ethyl ester, a novel synthetic second generation w-3 fatty acid which targets key drivers of hemolysis and multicellular adhesion. In preclinical studies in Townes humanized SCD mice and SCD patient RBCs, epeleuton acts as a disease-modifying agent by simultaneously decreasing (a) systemic and local inflammatory activation, (b) endothelial adhesion, (c) organ damage and (d) intravascular hemolysis and sickling. Epeleuton has been administered to 343 subjects in clinical trials, with a favorable safety and tolerability profile.

Objective

To evaluate the pharmacokinetics, pharmacodynamics and safety of orally administered epeleuton in patients with SCD.

Study Design and Methods.

This open-label, phase 2, multicenter study (NCT05861453) will enroll approximately 30 adult patients with a confirmed diagnosis of SCD (HbSS and HbSß0-thalassemia). Participants must have hemoglobin levels of 5.0-9.5g/dL at screening, 2-10 vaso-occlusive crises (VOCs) in the past 12 months, and a high adhesion index at screening defined as RBC laminin adhesion > 400 cells. Concomitant treatment with a stable dose of hydroxyurea is permitted during the study. Key exclusion criteria include receiving an RBC transfusion within three months of enrolment, receiving voxelotor, crizanlizumab or l-glutamine within six weeks of enrolment and, prior hematopoietic stem cell transplant.

The trial has a 28-day screening period, followed by a 16-week treatment phase and a 30-day post-treatment follow-up period. Study participants will attend the clinic on 6 occasions at screening, baseline, weeks 4, 8 and 16 (end-of-treatment) and the week 20 post-treatment follow-up visit. Enrolled patients will receive epeleuton 2g BID (4g daily) for 16 weeks. Study endpoints include change from baseline in hemoglobin levels, hemolytic markers, assessments of RBC health, soluble adhesion molecules, RBC adhesion, whole blood adhesion and rates of VOC.

Conclusion:

Treatments that can simultaneously target hemolysis and cellular adhesion may have an important disease-modifying utility for patients with SCD. The results of this study are anticipated to confirm the potential of epeleuton to address multiple aspects of SCD and to guide the design and conduct of future studies in patients with SCD.