A Phase 3 interventional study of Navtemadlin and Navtemadlin placebo in Myelofibrosis, Post-PV MF and Post-ET Myelofibrosis, sponsored by Kartos Therapeutics, Inc.. Recruiting at 215 sites in 19 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-09-25.
Sponsored by Kartos Therapeutics, Inc. · Phase 3, Interventional, and Treatment
This clinical trial is evaluating whether addition of navtemadlin to ruxolitinib treatment will provide more clinical benefit than ruxolitinib alone for patients with Myelofibrosis who have a suboptimal response to ruxolitinib treatment alone.
Subjects will start by receiving ruxolitinib alone in the run-in period. Those who demostrate a suboptimal response from ruxolitinib alone will then be randomized 2:1 to receive navtemadlin or navtemadlin placebo as add-on treatment to their ongoing ruxolitinib. Randomized means that subjects will be assigned to a group by chance, like a flip of a coin. The study is blinded, meaning the subjects, doctors, central endpoint assessors and sponsor will not know which add on treatment (navtemadlin or navtemadlin placebo) the subject is receiving.
419 studies on the registry are indexed under Primary Myelofibrosis; 117 are open to participants now.
This study's planned enrollment of 600 is above the median of 44 across 347 interventional studies indexed under Primary Myelofibrosis.
Browse Primary Myelofibrosis studies →Kartos Therapeutics, Inc. is the lead sponsor of 16 studies on the registry; 7 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Inclusion Criteria for Ruxolitinib Alone Period:
Exclusion Criteria for Ruxolitinib Alone Period:
Inclusion Criteria for Randomized Period:
Exclusion Criteria for Randomized Period:
Navtemadlin administered orally once daily on Days 1-7, off treatment on Days 8-28, in 28-day treatment cycles. Ruxolitinib administered orally twice a day.
Drug: Navtemadlin · Drug: Ruxolitinib
Navtemadlin placebo administered orally once daily on Days 1-7, off treatment on Days 8-28, in 28-day treatment cycles. Ruxolitinib administered orally twice a day.
Drug: Navtemadlin placebo · Drug: Ruxolitinib
Navtemadlin is an investigational MDM2 inhibitor
Also known as: KRT-232
Navtemadlin placebo
Also known as: KRT-232
Ruxolitinib is a janus kinase 1/2 inhibitor
Also known as: Jakafi, Jakavi
To compare spleen volume reduction (SVR35) between Arm 1 and Arm 2
The proportion of subjects in each arm with SVR35 by MRI/CT scan (central review) 24 weeks after start of the randomized period
Time frame: 24 weeks
To compare total symptom score reduction (TSS50) between Arm 1 and Arm 2
The proportion of subjects in each arm with a TSS50 by the Myelofibrosis Symptom Assessment Form (MFSAF) v4.0 24 weeks after start of the randomized period
Time frame: 24 weeks
To compare time to progression between Arm 1 and Arm 2
Time to progression or death from any cause in subjects randomized to each arm
Time frame: Up to 8 years
To compare overall survival (OS) between Arm 1 and Arm 2
Time to death from any cause in subjects randomized to each arm
Time frame: Up to 8 years
Showing the first 100 of 215 sites across 19 countries.
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Kartos Therapeutics, Inc.