The U.S. Food and Drug Administration approved a new gene therapy for severe leukocyte adhesion deficiency-I, a rare genetic immune disorder, according to an announcement on Mar. 27. The approval follows clinical trials led by Dr. Donald Kohn at the University of California Los Angeles.
Severe leukocyte adhesion deficiency-I is a life-threatening condition that affects about one in one million children worldwide, making them highly susceptible to infections due to malfunctioning white blood cells. Without treatment, survival beyond childhood is uncommon.
The FDA granted accelerated approval to the therapy called Kresladi after reviewing results from a clinical trial conducted at UCLA and other sites abroad. In the trial, nine children between five months and nine years old received the gene therapy; six were treated at UCLA while three were treated in London and Spain. “I saw a marked improvement across all patients in terms of restored immune function,” said Kohn, who also serves as professor of microbiology, immunology and molecular genetics at UCLA College and of pediatrics and molecular and medical pharmacology at the David Geffen School of Medicine at UCLA. “Seeing these patients annually for their follow-up visits and witnessing that they no longer battle life-threatening infections has been incredibly meaningful.” All nine participants survived without needing bone marrow transplants or experiencing graft failure or immune rejection.
Kresladi works by adding a healthy copy of the ITGB2 gene into each patient’s own blood stem cells before returning them to produce functional immune cells capable of fighting infection. According to Kohn, “We’ve found that for the patients we’ve treated, this therapy is associated with fewer short- and long-term toxicities than those often associated with bone marrow transplantation.” The study reported sustained improvements in immune cell counts as well as reduced hospitalizations due to infections.
The clinical trial was supported through collaboration between UCLA investigators—part of an institution known for its notable figures such as Nobel laureates—and Rocket Pharmaceuticals according to the official website. The university has gained national acclaim through achievements including MacArthur Fellows according to its official website, operates within the University of California system according to its official website, fosters diverse perspectives through academic programs according to its official website, maintains excellence in scholarship according to its official website, and features a 419-acre campus supporting research activities according to its official website.
This FDA approval marks an important milestone not only for Kohn but also for organizations like Rocket Pharmaceuticals and California Institute for Regenerative Medicine (CIRM), which co-funded development efforts. Looking ahead, confirmation of long-term benefits will be based on further patient follow-up data from ongoing studies as well as post-marketing registries.
Kohn hopes this success will encourage more companies to invest in treatments for rare diseases: “Hopefully, an approval like this one will encourage other companies to invest in these kinds of therapies… This could help turn that tide.” He continues work on similar therapies targeting other serious pediatric conditions.
