Ipsen acquires Kartos Therapeutics in $1.75 billion deal
Key takeaways
- The drug is currently in a Phase III trial called POIESIS, which is enrolling more than 600 patients across more than 250 sites globally.
- Ipsen CEO David Loew said in a statement that the deal "further strengthens our late-stage oncology pipeline" and that navtemadlin has the potential to become a new treatment option as early as 2028.
- Approximately 50% to 75% of patients on ruxolitinib discontinue treatment within three years, and median overall survival after discontinuation is roughly one to two years, the company said.
Ipsen acquires Kartos Therapeutics in $1.75 billion deal Ipsen acquires Kartos Therapeutics in $1.75 billion deal · Quartz · Dimitar Dilkoff / Getty Images Colleen Cabili Mon, June 29, 2026 at 8:50 PM GMT+7 2 min read IPN.PA Ipsen agreed to acquire Kartos Therapeutics, a Redwood City, California-based clinical-stage biopharmaceutical company developing a treatment for myelofibrosis, a rare blood cancer, for $450 million upfront and up to $1.3 billion in additional milestone payments, bringing the total potential deal value to $1.75 billion.
According to Reuters, the acquisition centers on navtemadlin, an oral MDM2 inhibitor being evaluated as an add-on therapy to ruxolitinib, the current standard of care for myelofibrosis, in patients who have a suboptimal response to that treatment. The drug is currently in a Phase III trial called POIESIS, which is enrolling more than 600 patients across more than 250 sites globally. Top-line data from that trial are expected in 2027, the company said.
Ipsen CEO David Loew said in a statement that the deal "further strengthens our late-stage oncology pipeline" and that navtemadlin has the potential to become a new treatment option as early as 2028.