Spruce Biosciences (SPRB) H.C. Wainwright 28th Annual Global Investment Conference summary

Pipeline and product overview

• Focused on rare and ultra-rare neuroendocrine diseases with significant unmet needs, aiming for best-in-class and first-in-class therapies.

• Lead asset is tralesinidase alfa, an enzyme replacement therapy for Sanfilippo Syndrome type B (MPS IIIB), acquired in late 2024.

• Product leverages a unique construct with an IGF2 linker, enhancing cellular uptake and making biosimilar competition difficult.

• Additional pre-IND monoclonal antibody program for congenital adrenal hyperplasia is not currently funded.

• Most resources are dedicated to advancing tralesinidase alfa (TA-ERT).

Clinical development and regulatory progress

• Inherited a robust five- to six-year clinical data set after prior sponsor discontinued studies due to funding issues.

• FDA now accepts heparan sulfate as a surrogate endpoint for neuronopathic MPSs, enabling accelerated approval pathways.

• Clinical program includes natural history studies and pivotal trials, with a confirmatory 301 trial designed in alignment with FDA.

• BLA submission planned for Q4 2026, with potential for priority review voucher and U.S. IP exclusivity through 2038.

• Multiple positive and collaborative pre-BLA meetings with FDA have clarified submission requirements.

Efficacy and safety data

• Tralesinidase alfa shows rapid and durable normalization of heparan sulfate in nearly all patients, with effect sizes surpassing competitors.

• Early treatment leads to improvements in cognition, motor skills, communication, and daily living activities.

• No observed shrinkage of cortical gray matter over time, suggesting neuroprotection.

• Drug is generally well tolerated; most adverse events are related to the delivery device, and anti-drug antibodies are not clinically significant in the brain.

• Data package includes evidence for both weekly and every-other-week dosing regimens.