Emapalumab With Post-Transplant Cyclophosphamide, Tacrolimus and Mycophenolate Mofetil for the Prevention of Graft-versus-Host Disease After Donor Reduced-Intensity Hematopoietic Cell Transplant

Description

PRIMARY OBJECTIVE:

I. Assess the safety and describe the toxicity profile of adding emapalumab to post-transplant cyclophosphamide (PTCy)-based graft-versus-host disease (GVHD) prophylaxis by day 28 post reduced-intensity hematopoietic cell transplantation (HCT).

SECONDARY OBJECTIVES:

I. Estimate activity of emapalumab, PTCy, tacrolimus (tacro) and mycophenolate mofetil (MMF) acute GVHD (aGVHD) prophylaxis, by cumulative incidence of aGVHD (grade 2-4) at day +100.

II. Estimate cumulative incidence of chronic GVHD (cGVHD) at 1-year post-HCT. III. Estimate overall survival (OS) and progression-free survival (PFS) at 1- year post-transplant.

IV. Estimate GVHD-free relapse-free survival (GRFS) at 1-year post-HCT. V. Estimate cumulative incidence of relapse/disease progression, and non-relapse mortality (NRM) at day +100 and 1-year post-HCT.

VI. Estimate the rate of grade 2 or higher infection at 100 days. VII. Assess time to engraftment (platelets and neutrophils).

EXPLORATORY OBJECTIVES:

I. Evaluate free emapalumab levels by serial blood sampling and assess association with severe aGVHD incidence.

II. Determine levels of interferon gamma (IFNgamma)-related inflammatory cytokines (CXCL-9 and CXCL-10) by serial sampling and assess association with free emapalumab levels and incidence of grade 3-4 aGVHD.

III. aGVHD biomarkers per Mount Sinai Acute GVHD International Consortium (MAGIC) criteria on days + 1, +7, +14 and +28.

IV. Describe the kinetics of immune cell recovery (B, T, natural killer [NK] cells) at days 30, +100, +180 and +365 post-HCT in peripheral blood.

V. Evaluate patient quality of life at baseline then on day +100, 6 months, and 1-year post-HCT using patient reported outcomes of Functional Assessment of Cancer Therapy-Bone Marrow Transplant (FACT-BMT).

VI. Obtain a preliminary estimate of gut microbiome diversity at baseline (preferably before fludarabine administration), and then on days +14, +28, +60, and +100 after HCT.

OUTLINE:

Patients receive fludarabine intravenously (IV) on days -7 to -3 and melphalan IV over 1 hour on day -2 or busulfan IV on days -7 and -6 and fludarabine IV on days -7 to -2. Patients receive HCT infusion on day 0 per institutional standards of practice. Patients also receive emapalumab IV over 1 hour on days -8. -1, -7, 14 and 21, cyclophosphamide IV on days 3 and 4, tacrolimus IV or orally (PO) on days 5-95, mycophenolate mofetil IV or PO on days 5-35. Additionally, patients undergo chest computed tomography (CT) and echocardiography (ECHO) or multigated acquisition scan (MUGA) at baseline and blood sample collection throughout the study.

After completion of study treatment, patients are followed up at 100 days after HCT, then at 6 months and 1 year.