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

Phase 2
Recruiting
Conditions
Primary Myelofibrosis (PMF)
Post-Polycythemia Vera MF (Post-PV-MF)
Post-Essential Thrombocythemia MF (Post-ET-MF)
Interventions
Drug: Best Available Therapy (BAT)
Registration Number
NCT03662126
Lead Sponsor
Kartos Therapeutics, Inc.
Brief Summary

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.

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
385
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)

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
Part A Cohort 3KRT-232KRT-232 240 mg by mouth once daily for Days 1-7, off treatment for Days 8-28 (28-day cycles)
Part A Cohort 4bKRT-232KRT-232 240 mg by mouth once daily for Days 1-5, off treatment for Days 6-28 (28-day cycles)
Part B Arm 1 KRT-232KRT-232KRT-232 240 mg by mouth once daily for Days 1-7, off treatment for Days 8-28 (28-day cycles)
Part B Arm 2 Best Available TherapyBest Available Therapy (BAT)Best available therapy at the discretion of the investigator, on a 28-day cycle.
Part A Cohort 1KRT-232KRT-232 120 mg by mouth once daily for Days 1-7, off treatment for Days 8-21 (21-day cycles)
Part A Cohort 2KRT-232KRT-232 240 mg by mouth once daily for Days 1-7, off treatment for Days 8-21 (21-day cycles)
Primary Outcome Measures
NameTimeMethod
(Part A Only) Spleen Volume Reduction (SVR)24 weeks

The proportion of subjects achieving a ≥ 35% spleen volume reduction (SVR) from Baseline to Week 24, as assessed by magnetic resonance imaging (MRI) or computed tomography (CT) scan

(Part B Only) Spleen Volume Reduction (SVR)24 Weeks

The proportion of subjects achieving SVR of ≥ 35% at Week 24 by MRI/CT scan (central review)

Secondary Outcome Measures
NameTimeMethod
(Part A only) Improvement in Total Symptom Score (TSS)48 weeks

The proportion of subjects who have at least a 50% reduction from Baseline to Week 24 and Week 48 in the total symptom score as measured by the modified MPN-SAF v2.0

(Part B only) Improvement of Total Symptom Score (TSS)24 Weeks

The proportion of subjects who have at least a 50% reduction from Baseline to Week 24 in the total symptom score as measured by the MF-SAF v4.0

(Part B Only) Overall Spleen Volume Reduction (SVR)48 months

The proportion of subjects in each arm achieving SVR of ≥ 35% at any time by MRI/CT scan (central review)

(Part B only) Overall Survival (OS)48 months

Time from randomization to death from any cause

(Part B only) Progression free survival (PFS)48 months

Time from randomization to either first occurrence of disease progression or death due to any cause

(Part B Only) Spleen Response Duration48 months

Time from initial SVR of ≥ 35% by MRI/CT (central review) until the first occurrence of disease progression

(Part B Only) Rate of conversion from RBC transfusion dependent to independent24 weeks

The proportion of subjects who have RBC transfusion independence at week 24

Trial Locations

Locations (191)

The Kirklin Clinic of UAB Hospital

🇺🇸

Birmingham, Alabama, United States

University of Southern California Norris Comprehensive Cancer Center

🇺🇸

Los Angeles, California, United States

Stanford Cancer Center - Palo Alto

🇺🇸

Stanford, California, United States

Innovative Clinical Research Institute

🇺🇸

Whittier, California, United States

University Cancer Institute

🇺🇸

Boynton Beach, Florida, United States

Northwestern University Feinberg School of Medicine

🇺🇸

Chicago, Illinois, United States

University of Illinois at Chicago

🇺🇸

Chicago, Illinois, United States

Dana-Farber Cancer Institute

🇺🇸

Boston, Massachusetts, United States

Washington University School of Medicine

🇺🇸

Saint Louis, Missouri, United States

Brookdale University Hospital and Medical Center

🇺🇸

Brooklyn, New York, United States

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The Kirklin Clinic of UAB Hospital
🇺🇸Birmingham, Alabama, United States

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