Company: KROS
Filing Date: 2025-02-26
Form Type: 10-K
Source: 0001664710-25-000018
Chunk: 111

Company: Keros Therapeutics, Inc.
Filing Date: 2025-02-26
Form: 10-K
Item: Item 1
Chunk 111
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 Jakafi developed treatment-related grade 3 or 4 anemia. Grade 3 or higher adverse events of anemia and thrombocytopenia were observed in approximately 34% and 12%, respectively, of patients evaluated in the Phase 3 clinical trial of Inrebic. The treatment-related cytopenias led to severe complications, dose reductions and reduced compliance.

In September 2023, momelotinib (Ojjaara) received approval from the FDA for the treatment of intermediate or high-risk myelofibrosis in adults with anemia. In a third-party Phase 3 clinical trial of Ojjaara versus danazol in patients with myelofibrosis who were symptomatic and anemic and had been previously treated with an approved JAK inhibitor, 25% in the Ojjaara arm achieved the primary endpoint of total symptom score reduction of at least 50%, compared to 9% in the danazol arm. Additionally, 31% in the Ojjaara arm achieved the secondary endpoint of transfusion independence, compared to 20% in the danazol arm. In a separate third-party Phase 3 clinical trial of Ojjaara versus ruxolitinib in JAK-naïve patients, in the subset of patients with anemia, a numerically lower percent of patients treated with Ojjaara (25%) achieved a total symptom score reduction of 50% or more at Week 24 compared with ruxolitinib (36%). In this trial, similar reductions in spleen volume reduction were observed with both Ojjaara (31%) and ruxolitinib (33%).

We believe elritercept has the potential to not only ameliorate myelofibrosis-associated cytopenias, but also improve spleen volume and patient-reported outcomes, alone or in combination with approved products regardless of the underlying mechanism of action of such products, including JAK inhibitors and Ojjaara.

Our Solution: Elritercept

Elritercept is a ligand trap comprised of a modified ligand-binding domain of ActRIIA that is fused to the portion of the human antibody known as the Fc domain. Elritercept is designed to bind to and inhibit the signaling of TGF-ß ligands involved in the regulation of hematopoiesis, including activin A, activin B and growth differentiation factor 11, that restrict blood cell progenitors from continuing through differentiation and developing into mature cells with