Spruce Biosciences keeps December BLA target for Sanfilippo therapy, spins off CRHX-101

Spruce Biosciences said on November 9, 2026 that it remains on track to submit a Biologics License Application in December 2026 for tralesinidase alfa enzyme replacement therapy (TA-ERT) in MPS IIIB. The submission would seek accelerated approval based on reduction of cerebrospinal fluid heparan sulfate non-reducing end as a reasonably likely surrogate endpoint of clinical benefit.¹ If approved, TA-ERT may be eligible for a rare pediatric disease priority review voucher, and there is currently no FDA-approved therapy for MPS IIIB.¹

An open-label, single-arm Expanded Access Program for TA-ERT in children with attenuated and severe MPS IIIB who cannot enroll in the TrAnsform confirmatory study was initiated in November 2026 and is expected to enroll approximately 10 participants.¹ Spruce completed the first PPQ batch in July 2026 and expects to complete the second PPQ batch in December 2026, ahead of the anticipated FDA mid-cycle review.¹ The planned TrAnsform confirmatory study, a randomized, single-blind, controlled trial in children 1 to 5 years old with severe MPS IIIB, is expected to enroll about 14 participants evaluating cognition as the primary objective, and the FDA requested the study begin while the BLA is under review.¹

On the financing side, Spruce amended its loan agreement with Avenue Capital Management II and Avenue Venture Opportunities Fund II on November 6, 2026, increasing Tranche 2 availability to up to $15.0 million drawable between January 1 and March 31, 2027, and extending the interest-only period through March 31, 2027, with potential further extensions through October 31, 2028.¹

Also on November 6, 2026, Spruce separated its CRHX-101 (formerly SPR-202) program, an anti-corticotropin-releasing hormone monoclonal antibody, into a newly formed wholly-owned subsidiary, Adrenyx Biosciences, contributing related assets and liabilities.¹ Spruce intends to distribute Adrenyx shares to its stockholders, aiming to create two independent public companies.¹ Adrenyx also entered a secured convertible note agreement for up to $10.0 million, with $5.0 million issued at initial closing.¹ The distribution is expected to complete in the first half of 2027, subject to conditions including SEC registration effectiveness and Nasdaq listing approval.¹

Cash and cash equivalents were $87.7 million as of September 30, 2026, up from $48.9 million at year-end 2025, which Spruce said it believes will fund planned operations and debt obligations into the second half of 2027.¹