Newsletter for families, partners and supporters A year of change, growth and hope Dear STAR families, clinician partners and supporters: This newsletter is filled with exciting news about change, progress and growth for both the STAR Foundation and our clinician partners in the FSASD Consortium. We are excited to share news and updates in this newsletter for November 2023. This past year was also a big change for us as we welcomed our beautiful little sister Lily to the Foglio family. As we approach the holiday season, we are filled with gratitude for all of you and hope for FSASD treatments. We ask for your continued support of STAR and for all our children through your generous donations. Please consider donating directly to STAR or creating a fundraiser this Giving Tuesday as we accelerate research and move closer to therapies! In gratitude, Mike and Jessica Foglio STAR Co-Founders/President Giving Tuesday is Tuesday 28 HIGHLIGHTS OF THIS EDITION November. Consider donating to STAR by Message from the Foglio Family - p. 1 scanning this QR code using Clinician and Family Meeting - p. 2-3 this link: FSASD Consortium Updates - p. 4-7 DONATE NOW STAR Fundraising Update - p. 8-9 STAR Data Collection - p. 10-11 STAR Contact Information - p. 12 NOVEMBER 2023, SIDE 1

Clinician and Family Meeting October 2023 A huge thank you to Jessica Foglio STAR and Marjan Huizing of NIH for planning an outstanding two day meeting for both STAR families and FSASD Consortium clinicians. Ten onsite clinicians and 26 virtual attendees attended a two day meeting. The meeting ended with a dynamic discussion and question & answer session with STAR families, who attended both in person and online. Eight STAR families attended in person from across the US and Europe. STAR patients in attendance had the opportunity to meet with occupational, vision and physical therapists while parents had time to connect and network. STAR siblings did their own networking (a lot of chasing each other and having fun!), and families and clinicians enjoyed a lively dinner together at a local hibachi restaurant. Thank you to all in person attendees for traveling to New York for this special event! Look for more photos throughout this newsletter and on the STAR website! STAR Scientific Advisory Board names new chairperson In 2023, we welcomed the Montague family (Jonathan, Nathalie and Akina) to the STAR family. Akina is newly diagnosed with Salla. Her father Jonathan has the unique expertise of being both a Salla parent and the CEO of a Biotechnology Company, HotSpot Therapeutics of Boston. Jonathan has agreed serve as the new chairperson for the STAR “We are not alone, and we Foundation Scientific Advisory Board. The board consists of seven can do something.” members, all clinical experts in rare diseases and FSASD. They will review -Jonathan, speaking of the grant submissions and future funding requests received by STAR for STAR family community scientific rigor and will make recommendations to the STAR Board of Directors about funding. Thank you Jonathan and welcome to your family! NOVEMBER 2023 PG 2

Highlights from the October 2023 meeting: The STAR Foundation wanted visiting families to participate in therapy sessions that they might not have access to at home: Cuevas Medek Physical Therapy was provided by Azriel Novogroder and Dorian Pascoe. Cuevas Medek is an unconventional, unique approach to physical therapy. The focus is not on using orthotics or braces but instead helping the patient find balance through using a series of postural control exercises. Vision Therapy was provided by Joy Beider. Vision therapy is not offered consistently across the U.S. Through use of color/strong contrast, this therapy is used to help Salla patients process what they are seeing. Occupational Therapy was provided by Kouli Nalpantidis. While, occupational therapy is a standard therapy offered to Salla patients, what makes Kouli exceptional is her knowledge of massage techniques to help alleviate tight, fisted hands. These wonderful photos were taken by our photographer, Daniel Shapiro. https://www.shapiroeventphoto.nyc/ NOVEMBER 2023 PG 3

Updates Consortium unveils new logo In the scientific literature, “Salla Disease” has been referred to multiple ways. “Salla Disease” (named after the region of Finland which is home to a large number of known cases) or “Intermediate” or “Infantile” Sialic Acid Storage Disorder. Consortium members will now use the same term “Free Sialic Acid Storage Disorder” (FSASD) in papers, publications and products to create a common term for collaboration. The Consortium logo is deep in symbolism. The stars represent the STAR Foundation. The red star symbolizes that each patient and research group is unique, and that many research directions are aligned. Stars are also a ‘beacon of hope – a shining light that guides the way;’ a symbol of positivity, happiness or renewal. The polyhedron shape represents global, multidisciplinary collaboration, and in an abstract way, the sialic acid molecule. Consortium grows to 46 members In 2023 the FSASD consortium has grown to 46 members from 18 research centers across five countries (USA, Finland, France, UK, Germany). Since January 2021 they have met virtually 12 times and twice in a hybrid format (in person & virtual). Members sign a non- disclosure agreement after each meeting which allows for free sharing of knowledge, data and resources. One and five year goals are stressed at each meeting. Accelerating Research Towards FSASD Therapy! NOVEMBER 2023 PG 4

Updates (continued) Active Research directions and accomplishments Natural History Study A pilot natural history study brought 8 FSASD families to the We are “signing a National Institutes of Health in Bethesda, Maryland. Each of contract with the patients was under age 10; the goal of the study is to ourselves as learn more about the symptoms and biochemistry of FSASD scientists” to via an extensive series of laboratory and clinical tests. accelerate therapies. At the October Consortium meeting, Dr Lynn Wolfe shared -Dr Walkley, speaking of the that “we have so much data right now, we are in the process FSASD Consortium of analyzing everything that we have.” The families will be contacted prior to data publication. Thank you to the STAR families that participated in this important study! NOVEMBER 2023 PG 5

Updates (continued) FSASD Cell and mouse models Consortium researchers achieved all of the following and reported on them in recent meetings (efforts partially funded by STAR Foundation): A mouse model mimicking the Finnish Salla variant that can now be used for research of specific disease symptoms (like neurodevelopmental issues) and to test candidate drugs. A variety of FSASD mouse and FSASD patients’ cultured cell lines to study disease mechanism and therapeutics. These include fibroblasts (skin cells), FSASD induced pluripotent stem cells (iPSCs), specific brain cell types derived from iPSCs such as neural stem cells, astrocytes and cortical neurons. A cell assay that can be used for screening an array of drugs, including ‘repurposing’ drugs, which are drugs that are already in clinical trials/FDA approved for other diseases, such drugs have a shorter path to FDA approval to test in humans for a new purpose. All cell lines, mouse samples, patient samples and other resources are being freely shared among consortium groups for further research. Why mouse models?? What is drug ‘repurposing’? Consortium scientist Dr Steven Walkley explained the use of mouse models during the parent session of the October meeting in New York. To find promising drug candidates, they must first be tested in cells, than an animal model (simple systems like zebrafish or mice). Creating these models take time! NIH has created a mouse model with the same Finnish Salla variant found in humans. The mice are born and appear normal, then develop the disease slowly (they can live for many months), so different drug therapies can be tested on them. If promising, and if the drug has not yet been tested in humans, they would need to be tested in larger animals first. If a drug HAS previously been tested in a human (but for a different disease or reason), it can be ‘repurposed’ and potentially used to treat a new disease, like FSASD. A ‘repurposed drug,’ because it has already been shown to be safe in a human being, would in theory be available to real patients more quickly. The Consortium’s plan (if funding is available) is to accelerate the process by having multiple labs test drugs simultaneously. This is labor intensive work and requires investment. NOVEMBER 2023 PG 6

Updates (continued) CRISPR technology publication Dr Ray Wang (Children’s Hospital of Orange County Specialists, Orange, CA) led a team publishing “Base editing corrects the common Salla disease SLC17A5 c.115C>T variant” in August 2023. See link or scan QR code below: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10506058/ Dr. Steven Walkley Retires from Albert Einstein College of Medicine At the Tarrytown,New York meeting, we celebrated the retirement of Dr Walkley from the Einstein College of Medicine. We are so grateful that despite his retirement, he will continue on as a member of our STAR and FSASD community. Dear Dr Walkley: Thank you for giving us hope and purpose amidst our diagnosis with Ben. It is because of your efforts at the Rose F. Kennedy Center that so many families like ours are motivated to bring treatments to rare disorders. You have instilled in us an unwavering belief that no disease is too rare for viable research and treatment options. We were the first family to be a part of your IDDRC initiative, and we are certain that this incredible program will forever be a shining jewel within the Rose F. Kennedy Center. Jessica and Mike NOVEMBER 2023 PG 7

Fundraising update Funds raised by STAR are directly impacting RESEARCH: STAR Donation to Greenwood Genetic Center (GGC): Funds donated by STAR allow Consortium members to have sialic acid values measured (a specialized method) by the same assay method in the same lab, freely and quickly at GGC. Sialic acid values have been measured in patient and mouse cell lines, urine and tissues (including mouse brain). These Sialic acid values help with FSASD diagnosis, disease mechanism and therapy response studies. STAR Donation to fund trainees at NIH Funds donated by STAR provided salary support for trainees Mary Hackbarth and Petcharat Leoyklang from 2020-2023, while they performed research dedicated to FSASD. Their work directly supported NIH accomplishments in mouse models and cell assays. STAR Donation to fund new grant to Université de Paris: STAR recently approved a grant to the laboratory of Dr Bruno Gasnier for his work focusing on drug identification and testing. Funding for this grant was made possible by generous donations from The Kaiser and Ammann families. Thank you! STAR Donation Albert Einstein School of Medicine Funds donated by STAR provided support to Dr Kostantin Dobrenis at the Rose F. Kennedy Center. Funding supports Dr Dobrenis’ work with mouse colonies in search of potential treatments. NOVEMBER 2023 PG 8

Fundraising update Fundraising will be used to directly support accelerating research to therapies for our children living with FSASD. Every fundraiser (large and small) helps! https://sallaresearch.networkforgood.com/projects/97052-salla- research (or scan QR code above) For fundraising advice or to make a directed donation Please reach out to Jessica Foglio ([email protected]) or STAR Treasurer Ken Klein ([email protected]) NOVEMBER 2023 PG 9

Data collection update This year STAR has placed a renewed emphasis on data collection and having a better understanding the demographics of our STAR community. There are approximately 250 known cases of Salla disease worldwide, but that number is likely to grow due to better awareness of the disease and genetic testing sites like 23 and Me, which tests for the SLC17A5 variants. At the October meeting, Jessica shared that she has heard from new STAR families after they received test results from 23 and Me indicating the presence of the Salla gene (or carrier), and a STAR family member on the call shared her experience finally receiving a diagnosis for her adult daughter. As our community grows and we hopefully move closer to therapies, at the recommendation of both the STAR SAB and FSASD Consortium clinicians, STAR will re-start a patient registry in 2024. MORE DETAILS ARE COMING SOON! At the October Consortium Meeting, STAR Data Manager shared some facts about the 77 Salla patient partners that are part of the STAR family: By country: NOVEMBER 2023 PG 10

Data collection (continued) At the October Consortium Meeting, STAR Data Manager shared some facts about the 77 Salla patient partners that are part of the STAR family: By age: Great question! A STAR parent noted 7 of the 8 patients at the in person meeting were female and asked are FSASD disorders more common in girls? The response from our clinical partners is - No. The numbers in the literature are even by gender. (Just a coincidence mostly girls were in attendance!) As you can see, our STAR community is international, live across several continents and speak many languages. We’ll do our best to provide content, like this newsletter, in multiple languages whenever possible. You’ll also notice our STAR “children” are not all children! 32% of our known STAR patients are adults (age 18 or older). At the in person meeting, Consortium geneticist Dr Ray Wang shared how important it is for parents of our adult STAR patients to stay engaged. Not enough is known about the trajectory of symptoms over the life of FSASD disease, and contributions from our adult STAR patients may help fill in those gaps. Contributions from every family to STAR data collection efforts are so valued and appreciated! Parent Preference Survey Thank to the 29 STAR families who responded to our July parent preference survey about data collection preferences. 45% of respondents would be willing to update a patient registry every 6 months; 34% said every 3 months. 93% prefer an email reminder when its time to respond to surveys. Topics like developmental milestones, current health issues, quality of life (for both the STAR patient and family) are all important to families to track as well as different therapies, diets and medications tried. Families would like to see data responses by gene variant. In early 2024, we will look to start collecting registry data from all our families, and returning that data back to you so that you can see what others in the community are experiencing. A full copy of the parent preference survey will be emailed back to all parents by the end of November. NOVEMBER 2023 PG 11

CONTACT US POSTAL ADDRESS: STAR Foundation P.O. Box 115 Golden’s Bridge, New York New and improved email: [email protected] website and social website: www.sallaresearch.org media content! facebook: facebook.com/sallaresearch instagram: instagram.com/sallaresearch linkedin: linkedin.com/company/salla-treatment-and-research-foundation Families - has your email address changed? send updates to STAR Data manager Agnes Jensen at [email protected] to make sure you receive STAR postings and news Thank Thank Thank you! you! you! www.canva.com - for support of our non-profit via a free account (used to create this newsletter) NOVEMBER 2023 PG 12