The clinical trial is called POIESIS. More than 600 patients. Over 250 sites worldwide.
It is testing navtemadlin as an add-on to the current standard of care for myelofibrosis. That is the specific institutional response to a known problem: ruxolitinib works for some, but not all.
For those it fails, the numbers are grim. Median overall survival after stopping ruxolitinib runs about one to two years. Ipsen, the French drugmaker listed on Euronext with an ADR on the U.S. market, is buying Kartos Therapeutics to get that drug.
Kartos is a private biotech based in Redwood City, California. The deal is definitive.
The asset is navtemadlin, an investigational MDM2 inhibitor. The mechanism: restore the tumor-suppressing function of p53. The target: patients with intermediate and high-risk TP53 wild-type myelofibrosis who have a suboptimal response to ruxolitinib.
The Paris headquarters announced the acquisition June 29. Chief executive David Loew said the move strengthens the company’s late-stage oncology pipeline. He described the effort as bringing transformational treatments to cancer patients.
He expressed excitement about navtemadlin’s potential to define a new treatment paradigm. That paradigm addresses what he called a critical care gap.
The earliest possible arrival of a new therapeutic option: 2028. Ruxolitinib is the standard of care. It improves splenomegaly and myelofibrosis-related symptoms.
But a significant proportion of patients get a suboptimal response. They discontinue treatment.
The outcomes after that are described as dismal. That is the gap. That is what the Phase III trial is designed to measure.
The POIESIS trial is global. It is enrolling now. It is testing navtemadlin as an add-on therapy.
The structure is straightforward: add the MDM2 inhibitor to the existing regimen. See if it changes the trajectory.
The trial design reflects a specific institutional strategy: go after the patients who fall through the existing treatment net. Ipsen is not a small player. It is headquartered in Paris, listed on Euronext, with an ADR on the U.S. market.
The acquisition of Kartos adds a late-stage asset to a pipeline that already has oncology focus. The company framed the deal as a continued focus on transformational treatments.
Loew did not mince words about the opportunity. He called it a critical care gap. He talked about a new treatment paradigm.
The drug itself is not new to development. Navtemadlin has been in trials. The POIESIS trial is the next step.
It is designed to enroll more than 600 patients. That is a large trial for a niche indication.
Myelofibrosis is not a common cancer. But the unmet need is clear. The median survival numbers after ruxolitinib failure are stark.
That is the clinical reality the trial is meant to address. The acquisition is definitive.
The mechanics are straightforward. Ipsen gets the drug. Kartos gets bought.
The patients get a potential new option. The timeline is long. 2028 is years away. But clinical development takes time.
The trial has to enroll. It has to read out.
The data has to be analyzed. The regulators have to review. That is the institutional process.
Loew expressed excitement about the potential. He did not promise results.
He described the acquisition as strengthening the late-stage pipeline. He said it reflects a continued focus on transformational treatments. The language is standard.
The substance is not. A drug that targets the p53 pathway in a specific genetic subset of myelofibrosis patients is a precise tool. The trial will show if it works.
