Company: KROS
Filing Date: 2025-05-06
Form Type: 10-Q
Source: 0001664710-25-000046
Chunk: 13

Company: Keros Therapeutics, Inc.
Filing Date: 2025-05-06
Form: 10-Q
Item: Item 1A
Chunk 13
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 include the most severe sufferers and their symptoms may have been bound to improve notwithstanding the new treatment. In addition, open-label clinical trials may be subject to an “investigator bias” where those assessing and reviewing the physiological outcomes of the clinical trials are aware of which patients have received treatment and may interpret the information of the treated group more favorably given this knowledge. Given that two open-label Phase 2 clinical trials are ongoing for elritercept, one in patients with lower-risk MDS and one in patients with myelofibrosis, the results from these clinical trials may not be predictive of future clinical trial results with these or other product candidates for which we include an open-label clinical trial, when studied in a controlled environment with a placebo or active control.

Our product candidates may be associated with serious adverse, undesirable or unacceptable side effects or other properties or safety risks, which may delay or halt their clinical development, or prevent marketing approval. If such side effects are identified during the development of our product candidates or following approval we may suspend or abandon our development of such product candidates, the commercial profile of any approved label may be limited, or we may be subject to other significant negative consequences following marketing approval. 

Undesirable side effects that may be caused by our product candidates could cause us or regulatory authorities to interrupt, delay or halt clinical trials and could result in a more restrictive label or the delay or denial of regulatory approval by the FDA or comparable foreign regulatory authorities. For example, in December 2024, we announced that we voluntarily halted dosing in the 3.0 mg/kg and 4.5 mg/kg treatment arms in our TROPOS trial evaluating cibotercept in patients with PAH based on a safety review due to the unanticipated observation of pericardial effusion adverse events at those dose levels. Subsequently, we announced in January 2025 that we voluntarily halted all dosing in the TROPOS trial, including the 1.5 mg/kg and placebo treatment arms, based on the ongoing safety review due to new observations of pericardial effusion adverse events. While KER-065 and elritercept have generally been well tolerated in our preclinical studies and clinical trials to date, the results from future preclinical studies and clinical trials, including of cibotercept and our other product candidates, may identify additional safety concerns or other undesirable properties of our product candidates. 

The results of our ongoing Phase 2 clinical trials of elritercept, our ongoing Phase 1 clinical trial of