KRT-232-115 – Blood Cancer Research WA

KRT-232 Versus Best Available Therapy for the Treatment of Subjects With Myelofibrosis Who Are Relapsed or Refractory to JAK Inhibitor Treatment (BOREAS)

A Phase 2/3 Randomized, Controlled, Open-Label Study of KRT 232 in Subjects With Primary Myelofibrosis (PMF), Post Polycythemia Vera MF (Post-PV-MF), Or Post Essential Thrombocythemia MF (Post-ET-MF) Who Are Relapsed or Refractory to Janus Kinase (JAK) Inhibitor Treatment

Myelofibrosis (MF)

This study evaluates KRT-232, a novel oral small molecule inhibitor of MDM2, for the treatment of patients with myelofibrosis (MF) who no longer benefit from treatment with a JAK inhibitor. Inhibition of MDM2 is a novel mechanism of action in MF.

This study will be conducted in 2 phases. Phase 2 will determine the KRT-232 recommended dose and dosing schedule; Phase 3 will test KRT-232 vs Best Available Therapy (BAT). Patients in the Phase 3 part of the study will be randomized 2:1 to receive either KRT-232 (Arm 1) or BAT (Arm 2). The BAT administered will be determined by the treating physician, with the option to “cross-over” to KRT-232 treatment after 6 months of BAT or if the disease worsens at any time.

Inclusion Criteria:

Confirmed diagnosis of PMF, post-PV MF or post-ET MF (WHO)
High, intermediate-2, or intermediate-1 risk Dynamic International Prognostic System (DIPSS)
Failure of prior treatment with JAK inhibitor
ECOG ≤ 2

Exclusion Criteria:

Prior splenectomy
Splenic irradiation within 3 months prior to randomization
History of major hemorrhage or intracranial hemorrhage within 6 months prior to randomization
History of stroke, reversible ischemic neurological defect or transient ischemic attack within 6 months prior to randomization
Prior MDM2 inhibitor therapy or p53-directed therapy
Prior allogeneic stem-cell transplant or plans for allogeneic stem cell transplant
History of major organ transplant
Grade 2 or higher QTc prolongation (> 480 milliseconds per NCI-CTCAE criteria, version 5.0)