Company: KROS
Filing Date: 2025-02-26
Form Type: 10-K
Source: 0001664710-25-000018
Chunk: 117

Company: Keros Therapeutics, Inc.
Filing Date: 2025-02-26
Form: 10-K
Item: Item 1
Chunk 117
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27) of patients with a TI response had ongoing TI as of the data cutoff date, of which 92.3% (n=12/13) had ongoing TI for greater than 52 weeks.

Additional data from the mITT24 patients, as of the data cut-off date, include:

•39.1% (n=27/69) of the TI-evaluable patients achieved TI for at least eight weeks over the first 24 weeks of treatment. 

•Of the patients with HTB, 31.4% (n=16/51) achieved TI for at least eight weeks during the first 24 weeks of treatment. Eight of those 16 patients (50.0%) achieved TI for at least 24 weeks over the first 48 weeks of treatment.

Studies in mainly lower-risk-MDS patients suggest that the majority (~90%) of patients have serum erythropoietin levels less than 500 U/L. Additionally, erythropoietin levels of ≥ 500 U/L are associated with lower erythroid response rates across 

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multiple treatments. Accordingly, we evaluated a subset of transfusion-dependent mITT24 patients with a baseline erythropoietin level less than 500 U/L (n=55), and observed the following, as of the data cut-off date:

•47.3% (n=26/55) achieved TI for at least eight weeks over the first 24 weeks of treatment. 

•Of the mITT24 patients with baseline erythropoietin level less than 500 U/L and HTB, 38.5% (n=15/39) achieved TI for at least eight weeks over the first 24 weeks of treatment.

The FACIT-Fatigue scale, a measure of self-reported fatigue and its impact upon daily activities and function, was utilized to assess health-related quality of life, including in a subgroup of patients (n=17) achieving TI for at least 24 weeks over the first 48 weeks of treatment. Patients in this subgroup showed clinically meaningful improvements in quality of life, and meaningful improvements in FACIT-Fatigue were observed early and generally continued to improve over time in patients with more durable TI responses.

The majority of patients enrolled in this ongoing trial had HTB and/or multi-lineage dysplasia, indicating a difficult-to-treat trial population. Durable TI responses continued to be observed in a broad range of patients with lower-risk MDS, including in those with HTB, which support