Edition | May 16, 2026
1. What’s the latest on the various Sanfilippo therapies working their way through the drug development pipeline?
Type A: UX111 has a PDUFA date. When Ultragenyx’s BLA resubmission for its UX111 gene therapy for Sanfilippo Syndrome Type A was accepted by FDA in April, it was assigned a PDUFA date of Sept. 19, 2026. A PDUFA date is a “target” action date set by the FDA, in which it aims to either approve the application, issue a Complete Response Letter (CRL), or take another formal regulatory action.
Type B: Spruce aiming for Q4 BLA for TA-ERT. Earlier this week Spruce announced that it continues to advance manufacturing readiness, regulatory interactions, and commercial planning to support an anticipated Biologics License Application (BLA) submission for its Tralesinidase Alfa Enzyme Replacement Therapy (TA-ERT) for Sanfilippo Type B in fourth quarter 2026. Spruce said it also continues to advance plans for a confirmatory study in patients with MPS IIIB and expanded access program to support continued patient access prior to and following potential approval.
Type B: Sangrail picks up ABO-101. Newly-formed Sangrail Biologics announced earlier this month SNG-101, a gene therapy for Sanfilippo Syndrome Type B (formerly known as ABO-101 under Abeona Therapeutics), as its lead clinical asset. Cure Sanfilippo Foundation was proud to be early funders of this program when it was run by Abeona and Nationwide Children’s Hospital, in which 14 children were treated with this intravenous AAV9 gene therapy.
Type C: U.S. location opens for Natural History Study. The “Natural History Study of Participants With Sanfilippo Syndrome Type IIIC” by Phoenix Nest is now recruiting at The University of Texas Southwestern Medical Center in Dallas, Texas, in addition to its already-running site in France. The two-year study combines a retrospective review of medical records and an ongoing collection of clinical data on an observational basis. Real-world data is collected at home using a recording device. Participants are asked to attend yearly in-clinic visits, which include neurocognitive, developmental, behavioral, biochemical, and imaging measures, as well as retrospective medical record analysis.
For more on these and other Sanfilippo studies and trials, visit the Foundation’s clinical trials webpage: https://curesanfilippofoundation.org/clinical-trials/
2. Who is running the FDA at this point?
As you’ve probably heard, Dr. Marty Makary resigned earlier this week as Commissioner (the top official) of the FDA. And just last month, Center for Biologics Evaluation and Research (CBER) Director Dr. Vinay Prasad left the agency too. These are two of the three top positions at FDA; the other being the Director of the Center for Drug Evaluation and Research (CDER).
Currently, all three positions are being filled by Acting Directors. Kyle Diamantas, a licensed attorney and the FDA’s Deputy Commissioner for Human Foods since January 2025, has been named as FDA’s Acting Commissioner while a permanent placement is sought. Dr. Tracy Beth Høeg, MD, PhD, is currently Acting Director of CDER, and Katherine Szarama, PhD, who was previously the Deputy Director under Dr. Prasad is currently Acting Director of CBER.
Which makes everyone wonder: How does the turnover in leadership impact rare diseases and drugs currently under review or about to begin the review process? The hope is that Diamantas, Høeg, and Szarama keep the FDA’s day-to-day operations, including its drug approval review process, moving. We, along with many other patient advocacy groups, are loudly voicing the need for consistency and expediency from the agency, even in this moment of change, to Congress, the agency, and publicly because patients’ lives are in the balance and every day matters.
3. Despite the change in regulatory leadership, we’re keeping patient voices at the forefront
Earlier this week, Foundation Chief Science Officer Cara O’Neill, MD, was in Washington, DC, to participate as a panelist and steering committee member for EveryLife Foundation for Rare Diseases’ Scientific Workshop. Thanks to the ELF team for hosting an incredible day of discussion and forward-solutions based thinking from FDA, drug developers, and rare advocates.
While in DC, Cara and Foundation Board Member Jessica Haywood joined other members of EveryLife’s Community Congress to also meet with multiple congressional offices. Discussions highlighted the rare disease community’s priorities for the upcoming Prescription Drug User Fee Act (PDUFA) VIII reauthorization, as well as the status of rare disease treatments with FDA and the continued urgent patient need for safe and effective therapies. Over the past two years, Cure Sanfilippo Foundation, along with other community members and families, have been in DC regularly to advocate for Sanfilippo patients and families.
4. Would you like some help with an upcoming fundraising event?
The weather is finally turning warmer and many families’ minds are turning to fundraising ideas, especially with so much momentum happening. Did you know that you don’t have to figure out all the logistics of running fundraisers like 5Ks, lemonade stands, golf outings, etc. on your own? The Foundation has lots of experience and best practices and are happy to work with you to lighten the load of hosting a fundraising event. In addition to experience, the Foundation can also help with event registration, event contracts, signage, and more. If you’d like some support with a Foundation fundraiser, reach out to Foundation Senior Development Manager Lindsey Shealy at Lindsey@CureSanfilippoFoundation.org.
5. Have you blocked your calendar for ADVANCE 2026?
ADVANCE is the Foundation’s free virtual conference where families and caregivers, scientists and researchers, clinicians and therapists, advocates, biotechs, and supporters all come from around the world to engage and advance the work to help children with Sanfilippo Syndrome. Mark your calendars for our information-packed ADVANCE 2026 virtual conference on Sept. 22 & 23. Registration information will be coming out soon. And thanks to the many parents who provided input that is helping shape this year’s agenda and content!
Why attend ADVANCE 2026?
- ADVANCE is a Sanfilippo Syndrome-specific conference that brings together the patient/family, research, clinical, educational, and industry communities together.
- It’s virtual and global, so you can attend from wherever you are.
- Hosted by Cure Sanfilippo Foundation, it is free for all to attend.
- You hear directly from many of the world’s leaders in Sanfilippo research, therapy development, and more, as well as get to ask them your questions.
- Hear updates on ongoing and upcoming clinical trials for Sanfilippo.
BONUS: Hooray for MPS Awareness Day!
It was amazing and emotional to see your families and supporters filling social media with purple yesterday for MPS Awareness Day. Moments like these you realize, we’re not so rare after all.
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