Spruce advances MPS IIIB therapy BLA plan

• Spruce Biosciences completed two FDA pre-BLA meetings supporting its planned Biologics License Application for tralesinidase alfa in MPS IIIB.
• The FDA found Spruce’s chemistry, manufacturing, and controls comparability strategies reasonable following technology transfer to a commercial-scale manufacturer.
• Spruce stated that it remains on track to submit the BLA in the fourth quarter of 2026 under the accelerated approval pathway.

Spruce Biosciences (NASDAQ:SPRB) announced that it completed two pre-BLA meetings with the U.S. Food and Drug Administration supporting its planned submission of a Biologics License Application for tralesinidase alfa enzyme replacement therapy in Sanfilippo Syndrome Type B.

The company stated that the FDA provided feedback on manufacturing plans and the planned BLA structure, while Spruce continues pursuing accelerated approval based on reduction of cerebrospinal fluid heparan sulfate non-reducing ends.

Spruce stated that the FDA found its drug substance and drug product analytical comparability strategies reasonable following technology transfer to a global biologics manufacturer, and the company aligned with regulators on integrated efficacy and safety summary formats.

The company stated that it remains on track for a fourth-quarter 2026 BLA submission.

Spruce completed the transfer of drug substance and drug product manufacturing and produced the first process performance qualification batch in July 2026, with a second batch planned for completion in the fourth quarter of 2026.

Tralesinidase alfa is being developed as an enzyme replacement therapy for Sanfilippo Syndrome Type B, a rare genetic disorder caused by NAGLU enzyme deficiency and associated with progressive neurological decline.