Chugai Slides After Ending Trials for Muscle Disorder Drug

Chugai Pharmaceutical Co. fell 7.3%, the largest intraday decline since August 2025, after the company said it had ended the development of an experimental drug for certain diseases that cause muscle weakness.

The decision doesn’t affect Chugai’s obesity drug development and isn’t expected to impact its earnings forecast for the fiscal year ending December, the Japanese drugmaker said in a statement Monday.