Keros Therapeutics Halts Dosing in Trial Due to Adverse Events

Biopharmaceutical company Keros Therapeutics, Inc. (NASDAQ:KROS), currently in the clinical stage, experienced a significant decline in its stock value following the announcement of a voluntary halt in dosing for certain arms of the Phase 2 TROPOS Trial. This decision was made after unexpected cases of pericardial effusion (a condition characterized by excessive fluid accumulation around the heart) were identified during a safety review among trial participants.

The fully enrolled TROPOS trial is evaluating the safety and efficacy of cibotercept (KER-012) in conjunction with standard treatment in patients with pulmonary arterial hypertension (PAH). Adverse events led the company to halt dosing in the 3.0 mg/kg and 4.5 mg/kg treatment arms. However, dosing at the 1.5 mg/kg level will continue following a risk-benefit assessment conducted by an independent Data Monitoring Committee (DMC) and a selected group of unblinded individuals at Keros.

Jasbir S. Seehra, Ph.D., Chairman and CEO of Keros, emphasized the company's commitment to patient safety, stating, "We are working diligently to better understand these unexpected findings." He also confirmed that Keros is actively collaborating with trial investigators, the U.S. Food and Drug Administration (FDA), and other regulatory bodies to address the issue swiftly.

Although dosing has been halted for the higher treatment arms, Keros will continue to collect safety and efficacy data for all groups involved in the trial. The company informed trial investigators and the FDA of the dosing halt and is in the process of notifying other relevant regulatory agencies. Keros anticipates presenting topline data from all treatment arms of the TROPOS trial in the second quarter of 2025 and will provide additional information as significant developments occur.