June 30, 2025, New York, NY – RTW Foundation, the philanthropic arm of RTW Investments, is proud to announce a significant step forward in the development of a potential gene therapy for NEDAMSS (Neurodevelopmental Disorder with Regression, Abnormal Movements, Loss of Speech, and Seizures), an ultra-rare disease caused by mutations in the IRF2BPL gene.
On March 19, 2025, the U.S. Food and Drug Administration (FDA) approved an Investigational New Drug (IND) application to allow the use of an experimental gene replacement therapy in a NEDAMSS patient, Elly Krueger. This clearance came just 13 months after Elly’s diagnosis, marking an unusually rapid timeline in the context of gene therapy development.
In February 2024, Elly's parents, Michelle and Dan Krueger, quickly connected with IRF2BPL preclinical gene therapy researcher Kathrin C. Meyer, PhD, and the rare disease advisory team at RTW Foundation shortly after. On April 3, 2025, Elly Krueger became the first child to receive an IRF2BPL gene replacement therapy at Weill Cornell Medicine in New York City.
Michelle and Dan Krueger launched Elly’s Team, a family-led rare disease advocacy organization, in February 2024 shortly after receiving the news of Elly’s NEDAMSS diagnosis, to pursue therapeutic options. NEDAMSS is an ultra-rare neurodegenerative disorder characterized by progressive neurological decline with developmental regression affecting motor function, speech, vision, and often causing seizures. Elly’s Team began collaborating with RTW Foundation’s Rare Disease Advisors in late February 2024, to assemble a multidisciplinary team of researchers, clinicians, and regulatory advisors to explore a gene therapy approach. Together, the team navigated drug development in real-time and achieved FDA approval to proceed with an IND application just 13 months after Elly's diagnosis, a process that typically takes many years and tens of millions of dollars to complete.
RTW Foundation launched its Rare Disease Advisory Program in 2024, to offer free consulting services to rare disease families and foundations like Elly’s Team, focused on therapeutic development. The goal is to provide high touch, tailored scientific expertise in order to facilitate effective drug discovery pathways. Under the direction of Joe Katakowski, PhD, Director of Research at RTW Foundation, the team has advised 29 foundations and reached over 45 families.
This milestone represents a turning point for Elly’s Team, RTW Foundation, and the entire IRF2BPL community. NEDAMSS, like most ultra-rare diseases, has had no treatment options until this point. This investigational IRF2BPL gene replacement therapy offers a potentially new therapeutic option for families in the IRF2BPL community.
“At the beginning, we talked to anyone and everyone in the space about all of the different treatment or care options, including all specific aspects of pursuing a gene therapy,” said Michelle Krueger. “And through many of those calls, Joe joined us. He took notes. He digested it. He spoke to the scientists in ways that we never could have. And then we debriefed afterwards, and he told us his thoughts, what we should pursue and where we should move forward. He also helped us determine when we hit a dead end. This consistent and scientifically based advice allowed us to make decisions and move quickly.”
As of two months post-treatment, the investigational therapy has been reported to be well tolerated. Ongoing monitoring and follow-up are in place to continue to evaluate safety and any potential clinical outcomes.
“Our partnership with Elly’s Team is a powerful example of what we hoped to achieve when we started the foundation,” said Stephanie A. Sirota, President of RTW Foundation. “While we know every story is different, Elly’s journey shows how helping one person can inspire others in similar situations, and provide a new path for families navigating the unknown.”
“This collaboration represents what is possible when families, scientists, and foundations work together with urgency and purpose,” said Joe Katakowski. “While this treatment remains investigational and its effects are still being studied, we hope this approach will offer a path forward not only for NEDAMSS but for other ultra-rare conditions with no approved therapies.”
There are over 10,000 rare diseases with 95% of those diseases lacking treatment globally. RTW Foundation’s Rare Disease Advising Program will continue to provide free services and expertise to support families and foundations navigating the path toward treatment. To learn more about partnering on future rare disease therapeutic efforts, visit the RTW Foundation website.
Elly’s Team
Elly’s Team is a faith-based foundation established with a singular goal of translating medical research to treatment in record time. Their path to treatment involves funding additional research to understand the disease mechanism and effects on the body, developing and manufacturing drugs, navigating the FDA approval process and clinical trials, and treating children.
About RTW Foundation
Founded in 2018 as the philanthropic arm of RTW Investments, LP, RTW Foundation works to power community initiatives and provide scientific advising to improve the health of underserved populations. The Foundation supports the development of medicines for neglected rare diseases, empowers youth to explore careers in science, biotechnology, and medicine, and builds partnerships with local organizations to advance health equity in New York City. To learn more, visit www.rtwf.org.