Ipsen has completed its acquisition of Kartos Therapeutics, adding the late-stage oncology drug navtemadlin to its pipeline as the company expands its presence in myelofibrosis.
Kartos is a clinical-stage biopharmaceutical company developing navtemadlin, an oral MDM2 inhibitor currently in Phase III clinical development.
Navtemadlin is being developed as an add-on treatment to ruxolitinib for patients with myelofibrosis who have a suboptimal response to the standard therapy.
The Phase III POIESIS study is evaluating whether adding navtemadlin to ruxolitinib can improve clinical outcomes compared with ruxolitinib alone.
Early clinical results cited by Ipsen suggest navtemadlin could potentially improve suboptimal responses to ruxolitinib among patients with intermediate- and high-risk TP53 wild-type myelofibrosis.
Myelofibrosis is a myeloproliferative neoplasm involving abnormal proliferation of hematopoietic stem cells and progressive fibrosis of the bone marrow.
As bone marrow function declines, blood production can move to other organs, particularly the spleen, potentially causing splenomegaly.
Patients can experience bone marrow failure, fatigue, night sweats and other progressive symptoms, and the disease can transform into acute myeloid leukemia.
Ipsen said the median age at diagnosis is approximately 67 to 69 years, and myelofibrosis affects about 1.5 people per 100,000 in the U.S. and Europe.
Approximately 75% to 89% of patients are classified as intermediate- or high-risk at diagnosis, while more than 95% are TP53 wild-type.
Ruxolitinib is currently used as a first-line standard of care, but Ipsen estimates that a significant proportion of patients experience an initially suboptimal response and approximately 50% to 75% discontinue therapy after three years.
Median overall survival following treatment discontinuation is typically one to two years, highlighting the need for therapies that can improve or extend treatment response.
The acquisition strengthens Ipsen’s late-stage oncology pipeline and adds another externally developed asset to a portfolio spanning oncology, rare diseases and neuroscience.
Ipsen operates in more than 40 countries and provides medicines to patients across more than 100 countries.
