Keros Therapeutics Halts Dosing In Phase 2 Trial Of Cibotercept Combination In PAH; Stock Plunge 65%

(RTTNews) - Biopharmaceutical company Keros Therapeutics, Inc. (KROS) announced Thursday that it has voluntarily halted dosing in the 3.0 mg/kg and 4.5 mg/kg treatment arms in the ongoing TROPOS trial based on a safety review due to the unanticipated observation of pericardial effusion adverse events in the trial.

TROPOS trial is a Phase 2 clinical trial of cibotercept (KER-012) in combination with background therapy in patients with pulmonary arterial hypertension (PAH).

The TROPOS trial is fully enrolled, and dosing in the 1.5 mg/kg treatment arm remains ongoing following completion of a risk and benefit assessment of the data from the ongoing trial that was conducted by the independent Data Monitoring Committee (DMC) followed by a select group of unblinded individuals at Keros.

The decision to halt the dosing in 3.0 mg/kg and 4.5 mg/kg treatment arms and continue dosing in the 1.5 mg/kg treatment arm was made in consultation with the independent DMC for the trial.

The Company intends to continue ongoing safety and efficacy data collection for all treatment arms in the trial.

The Company has notified investigators and certain regulatory authorities, including the FDA, about this decision, and is in the process of notifying other relevant regulatory authorities.

The Company continues to expect to present topline data from all treatment arms in this trial in the second quarter of 2025.

The Company is working diligently to investigate and address this matter and expects to provide additional information when there is a material update.