In a remarkable advancement for rare disease treatment, Andelyn Biosciences has successfully manufactured and delivered a novel viral vector gene therapy for a baby suffering from an ultra-rare neurodegenerative condition. The therapy, developed using Andelyn's AAV Curator Platform, was administered to treat Neurodevelopmental Disorder with Regression, Abnormal Movements, Loss of Speech, and Seizures (NEDAMSS), a devastating disease with no previously available treatments.
The therapy was produced in just 10 months from the start of development and administered only 14 months after the patient's initial diagnosis, representing an extraordinary timeline in the typically lengthy process of gene therapy development.
Rapid Response to a Devastating Diagnosis
Elly Krueger was diagnosed with NEDAMSS on February 8, 2023, when she was just 8 months old. Her condition, caused by a mutation in the IRF2BPL (Interferon regulatory factor 2 binding protein-like) gene, was progressing rapidly. NEDAMSS affects the central nervous system and can severely impact motor skills, speech, eating, eyesight, and often causes seizures.
"On April 3rd, 2025, Elly became the first child to receive an IRF2BPL gene replacement therapy at Weill Cornell in New York City," said Michelle Krueger, Elly's mother. "This achievement marks a major milestone, not only for our family but also for the entire IRF2BPL community."
The Krueger family established Elly's Team, a foundation dedicated to finding treatments for NEDAMSS. Through their network and determination, they identified gene therapy as a potential treatment option and selected Andelyn Biosciences to develop and manufacture the therapeutic.
Innovative Platform Enables Rapid Development
Andelyn's AAV Curator Platform utilizes what the company calls "Optimization-by-Design," a data-driven approach that correctly sizes processes for scale and speed to clinical application. The platform is designed to be highly predictable in terms of yield and quality, while eliminating intellectual property concerns through internally developed technology.
Wade Macedone, CEO of Andelyn Biosciences, emphasized the company's commitment to individual patients: "Supporting single-patient projects is part of the DNA of Andelyn Biosciences and the lifestyle of everyone who works at the organization. As a company we are as proud of successfully completing single-patient programs as we are scaling a manufacturing process for 10,000 or more patients."
The platform's established protocols allowed for streamlined FDA review, as the referenced Drug Master Files have been previously reviewed and approved, removing potential regulatory hurdles that could delay treatment.
Promising Early Results
One month after treatment, reports indicate the therapy has been safe and well-tolerated, with Elly "doing very well." While it remains too early to fully assess efficacy, the initial safety profile is encouraging for both the Krueger family and the broader NEDAMSS community.
The FDA has shown support for expanding this treatment to other children affected by the same condition, potentially opening a pathway for more widespread application of this therapeutic approach.
Implications for Ultra-Rare Disease Treatment
This case highlights the evolving landscape of personalized medicine and gene therapy for ultra-rare conditions. Traditionally, pharmaceutical companies have focused on more common diseases with larger patient populations, leaving those with extremely rare conditions with few treatment options.
The successful development and administration of this therapy demonstrates how targeted genetic interventions can be developed rapidly when academic researchers, manufacturing partners, and determined families collaborate effectively.
Michelle Krueger noted the personal connection that developed during the process: "Throughout this experience, the Andelyn Biosciences team became like part of our family. Everyone at the company knew the importance of speed. Many of them met Elly, held her, and prayed for her. Every step of the way, they knew there was a purpose beyond the vial – for Elly and all the other children affected by this devastating disease."
The achievement represents a significant step forward in making gene therapies more accessible and timely for patients with rapidly progressing rare genetic conditions, potentially establishing a model for future development of personalized genetic medicines.
