Takeda is paying Keros Therapeutics $200 million upfront to bolster its late-stage cancer pipeline. The outlay, plus up to $1.1 billion in milestones, has secured Takeda ex-China rights to a molecule that could compete with Bristol Myers Squibb’s Reblozyl in blood cancer indications.
The deal covers the activin inhibitor elritercept. Keros is developing the drug candidate to treat anemia seen in blood cancers including myelodysplastic syndromes (MDS) and myelofibrosis (MF). Teresa Bitetti, president of Takeda’s global oncology unit, outlined the opportunity and why the drugmaker believes elritercept can capture the market.
“Myelodysplastic syndromes and myelofibrosis are characterized by inadequate blood cell production, often leading to severe anemia that significantly impacts patient health and quality of life,” Bitetti said via email. “Early clinical results for elritercept have shown promising clinical activity and a manageable safety profile, highlighting its potential for patients with these cancers.”
Bitetti’s belief in the molecule is built on data from phase 2 trials Keros is running in MF and very low-, low- and intermediate-risk MDS. Keros sees elritercept as a molecule that can act on all stages of platelet and red blood cell production, leading it to identify opportunities across a broad patient population. But the initial focus is on people with more advanced disease, as Keros CEO Jasbir Seehra, Ph.D., explained.
“In [MDS] patients that have a greater disease burden, those that have a high transfusion burden, we have demonstrated a response rate of in the 40s, whereas luspatercept (Reblozyl) has a 20% response rate there. It's a much better response rate,” Seehra said at a Guggenheim Securities event last month. “In addition, we've demonstrated a more durable response in these harder-to-treat patients.”
More than half of patients in the elritercept were still on treatment after more than one year, Seehra said. Median duration of treatment on Reblozyl was 30 weeks, according to the CEO, “driven primarily by the low transfusion burden patients.” If everyone stopped therapy immediately after the last data cutoff, the median duration of treatment in the elritercept study would still exceed 52 weeks, the CEO said.
Keros will share more data at the American Society of Hematology Annual Meeting and Exposition next week. The updates will cover the durability of the responses to elritercept and quality of life data. Keros has identified the fatigue experienced by some people on Reblozyl as a way to differentiate its molecule.
“It is a common thing we hear from physicians,” Seehra said. “The patient is on luspatercept. They don't feel great. They're feeling fatigued. They want to come off and yet the physician knows that ... reducing the transfusion burden is good for them. It's a tug of war between the patient and the physician. We have demonstrated that elritercept actually reduces fatigue and we see that in patients pretty quickly.”
Keros is preparing to start a phase 3 trial in adult patients with transfusion-dependent anemia with very low-, low- or intermediate-risk MDS. Sales of Reblozyl, which is approved in very low- to intermediate-risk MDS, jumped 80% to $447 million in the third quarter. Takeda plans to study elritercept in MDS and MF across different patient segments and lines of therapy.
In MF, Keros has linked elritercept to reductions in spleen size and symptom scores. The phase 2 data suggest there may be a role for the molecule in the management of the dose-limiting low platelet levels seen in some people who take Incyte’s Jakafi to treat MF.