Seikagaku (TYO:4548) resubmitted its biologics license application to the U.S. FDA for SI-6603 (condoliase), a potential treatment for lumbar disc herniation, according to its Tokyo bourse filing on Tuesday.

The resubmission follows a complete response letter (CRL) received in March 2025, which raised no concerns about the drug's clinical efficacy or safety but cited issues related to the manufacturing facility and quality control.

The CRL is an FDA notification that an application will not be approved in its current state after review.

Seikagaku has since addressed these observations and is working with licensing partner Ferring Pharmaceuticals to pursue approval and offer a new non-surgical option for reducing leg pain associated with the condition.