Keros Therapeutics Halts TROPOS Trial Due to Safety Concerns

Keros Therapeutics, Inc., a clinical-stage biopharmaceutical company focused on addressing disorders linked to TGF-ß signaling, has announced a voluntary halt to all dosing in its Phase 2 TROPOS trial of cibotercept (KER-012) for pulmonary arterial hypertension (PAH). This decision follows the observation of pericardial effusion adverse events, which previously prompted the suspension of higher-dose treatment arms in December 2024. The company has decided to terminate the trial early to prioritize patient safety.

“We are disappointed by this development, but our commitment to patient safety remains unwavering,” stated Jasbir S. Seehra, PhD., Chair and CEO of Keros. Despite the early termination, Keros plans to present topline clinical data from all treatment arms in the second quarter of 2025. Regulatory authorities, including the FDA, have been notified, and patients will continue to be monitored through their end-of-trial visits as part of the company’s safety protocols.