A 15-year-old from Alexandria was scheduled to ring a bell at a New Orleans hospital Friday morning, marking a milestone after a grueling months-long treatment that doctors say has left him functionally cured of sickle cell disease. Phillip Mullin, a student at Holy Savior Menard High School, went through stem cell collection, blood exchange procedures, chemotherapy and a difficult recovery before reaching this point.
Mullin is just the second person and the first pediatric patient to undergo this new gene therapy treatment for sickle cell disease in Louisiana, according to kalb.com. The outlet reports that Mullin has been functionally cured of the illness according to Manning Family Children's, and Louisiana State Representative Ed Larvadain III said his treatment marked the first time the LYFGENIA product had been used anywhere in the state. He was scheduled to ring the bell at Manning Family Children's in New Orleans around 10 a.m. Friday, a ceremony that has become a symbolic milestone for patients completing the therapy.
How the Gene Therapy Works
The treatment Mullin received is one of two gene therapies the FDA approved for sickle cell disease: Casgevy, made by Vertex Pharmaceuticals, and Lyfgenia, made by Bluebird Bio, according to NBC News. The process involves collecting a patient's own stem cells, using a gene-editing tool to modify them, clearing out the body's existing stem cells with chemotherapy, and then reinfusing the edited cells. NBC News describes it as a very high-risk treatment requiring high-dose chemotherapy with potential for complications, which helps explain why Mullin's road included months of preparation and a challenging recovery.
The FDA's own materials describe Casgevy and Lyfgenia as the first cell-based gene therapies approved for sickle cell disease in patients 12 and older, specifically for those with recurrent vaso-occlusive crises. That age threshold is part of why Mullin's case stands out: at 15, he fits within the narrow window where pediatric patients can access the treatment at all.
Louisiana's First Functional Cure Came Months Earlier
Mullin's bell-ringing follows that of Daniel Cressy, a 23-year-old who became the first patient in Louisiana and the broader Gulf South to be functionally cured through gene therapy, according to Tulane University. Cressy received the Casgevy therapy, and his genetically modified cells were infused 100 days before he rang the bell at the hospital, marking what the hospital described as his functional cure.
At the time of Cressy's milestone, Manning Family Children's had five more patients undergoing the treatment, with nine others in the pipeline, per Verite News. A Tulane report quotes a doctor saying Manning Family Children's was then the only facility in Louisiana able to deliver gene therapy, which helps explain why both Cressy and Mullin ended up at the same New Orleans hospital despite living in different parts of the state.
A Disease That Disproportionately Affects Black Patients
Sickle cell disease affects more than 100,000 people in the United States, over 90% of whom are Black, according to Tulane University. In Louisiana alone, an estimated 3,000 people live with the condition. The hospital has said advances in genetically modified stem cells may mean many more children and young adults can be treated, and functionally cured, in the years ahead.
Still, access to these therapies remains far from simple. High costs, a demanding treatment process and limited access to sickle cell specialists have slowed their use nationally, according to CNBC. By the end of 2025, only 64 patients worldwide had received infusions of Casgevy, the outlet reported, citing figures from Vertex Pharmaceuticals.
Similar cases have surfaced elsewhere around the country as hospitals work through long waitlists for the specialized treatment. A 17-year-old in Knoxville, Eric Macklin, was pursuing gene therapy using his own genetically modified stem cells after chemotherapy, according to WATE. In the St. Louis region, Martin Mwita Jr. became the first patient there to receive an FDA-approved sickle-cell gene therapy, also using Lyfgenia, according to WashU Medicine. For Mullin and his family in Alexandria, the bell-ringing scheduled for Friday was set to cap a treatment journey that, for now, remains available to only a small number of patients willing and able to navigate it.
