Merck Halts Keytruda Trial for Extensive-Stage Lung Cancer

Drugmaker Cites Immune-Mediated Adverse Events

Trial Discontinuation Marks Setback for Anti-TIGIT Therapy

Merck & Co. announced Thursday the discontinuation of a late-stage clinical trial evaluating a combination immunotherapy treatment for patients with extensive-stage lung cancer.

The trial, known as KEYNOTE-926, was assessing the efficacy and safety of Merck's anti-PD-1 therapy Keytruda (pembrolizumab) in combination with tiragolumab, an anti-TIGIT antibody.

According to Merck, the trial was halted due to an increased incidence of immune-mediated adverse events (IMAEs), which include side effects such as pneumonitis, colitis, and hepatitis. These adverse events were more common in patients receiving the combination therapy than in those receiving Keytruda alone.