Happy to have given birth in January 2015 to two seemingly healthy boys, Levi and Colton, after an uneventful pregnancy, Kala Looks gave little thought to the routine heel prick of newborn screening. At 23 and 24, she and her husband, Phillip, were high school sweethearts starting a family.
Two weeks later, a Michigan state health official called. Something came up on Levi’s screen. You need to bring him in right away. Three weeks and numerous blood draws later, the Looks had a diagnosis: Severe combined immune deficiency (SCID) — “bubble boy” disease. Levi’s blood had only a few T cells, crucial ingredients of the immune system, and those were likely his mother’s lingering cells. Soon he would have no immune system at all.
That the fraternal twins are now healthy, active toddlers, climbing onto the dining room table and leafing through picture books and starting to talk, is thanks to newborn screening and a pioneering gene therapy trial at Dana-Farber/Boston Children’s Cancer and Blood Disorders Center.
Had Levi been born before October 2011, when Michigan began screening all newborns for “bubble boy” disease, he could well have died of overwhelming infection before his first birthday.
Instead, Levi has a functioning immune system after being treated in Boston as part of an international clinical trial of gene therapy for boys born with X-linked SCID. He is one of three boys treated on the trial’s U.S. arm whose disease was picked up by universal newborn screening, now standard in 42 states. Of the other four boys treated at U.S. sites, one from South America was diagnosed at birth, because an older brother had died of the disease. Three boys, from South America or states that didn’t yet have newborn screening, were diagnosed after suffering life-threatening infections that their bodies had trouble shaking.
Learning about gene therapy
Suddenly, after the SCID diagnosis, Levi was confined to his home, with no outside visitors, except his grandparents, allowed, and everyone in the house wearing masks. Levi started broad spectrum antibiotics. He needed a stem cell transplant, but that couldn’t be performed until he was three months old. Kala, a medical assistant, wouldn’t work for a year, and Phil, a diesel mechanic, would miss a lot of work.
“Levi was five weeks old. Starting to pick his head up. He had never been sick. We were just learning to cope with having twins,” Kala recalls. “It was terrifying. It changed our whole lives. We’re young. We had to grow up fast. We had to buckle down and do what was right for him.”
Doing what was right for Levi proved to be a difficult task. Colton, Levi’s twin, was not a match for the stem cell transplant. The family had a bone-marrow drive — but still no match. There was an umbilical cord that was a partial match, and doctors offered the option of using Kala’s cells as a half match. Then their physician at the University of Michigan told the Looks about the gene therapy trial at Dana-Farber/Boston Children’s. Three times Kala and Phil spoke with Sung-Yun Pai, MD, leader of the trial’s Boston site.
“I had never heard of gene therapy,” Kala says. “It was really hard. We prayed about it for a couple of weeks. Levi was 2½ months old. We had to make a decision. We told them we would do the half match with my cells. Then I said, ‘I don’t feel good about this.’ I read about Agustin, the Argentinian boy who’d been treated with gene therapy. It began to make more sense. We said, ‘This is what we’re doing.’”
On May 11, 2015, Pai harvested Levi’s bone marrow and sent his cells to the laboratory, where a so-called viral vector – a deactivated virus –inserted the corrected gene into his marrow cells’ DNA. On May 15, Kala pushed a button with Phil right beside her, and the new cells were delivered to their baby boy via an intravenous transfusion line. “Just seeing that white marrow go in, and knowing it was changed was really something,” Kala says.
Newborn screening sheds light on SCID
Thanks to newborn screening, Levi had never been sick.
In 2008, Wisconsin became the first state to screen newborns for SCID, followed by Massachusetts in 2009, according to the Immune Deficiency Foundation. In 2010, the federal Department of Health and Human Services announced the addition of SCID to its recommended newborn screening. Today 88 percent of newborns in the United States are screened for the disease.
One side effect of newborn screening has been a clearer understanding of the incidence of SCID. It was once thought that the immune disorder affected one in 100,000 live births. Since the adoption of widespread newborn screening, it is now estimated that the disorder affects one in 58,000 live births, with specialists positing that many infant deaths from infection were, in fact, due to SCID.
The Looks family had a scare when Levi developed a cold before the new, modified cells had taken hold. “I was terrified,” Kala says. “Then the gene therapy started to kick in. We could tell it was working because his running nose slowly went away.”
In November, Levi had his regular, periodic blood draw at the University of Michigan, and the sample was sent to Boston for analysis.
“Levi’s doing great. He’s thriving and growing, and you would never know the difference between him and his twin brother. We can see the corrected gene in his T cells, and his blood work looks essentially normal for his age,” Pai says. “If he had not been picked up at newborn screening, he could have died of an infection. He only had a partial match for a standard stem cell transplant, which wasn’t optimal. Because of newborn screening and gene therapy, he was diagnosed right away and treated with cells from his own body that wouldn’t cause transplant-related complications.”
Meanwhile, Kala has returned to work, and she and Phil have settled into the busy, lively routine that comes with raising two healthy toddlers.
“We wouldn’t have our son here today without newborn screening,” Kala says. “If we had him earlier or in a different state, it wouldn’t have been caught and there could have been a totally different outcome.”
Learn more about gene therapy at Dana-Farber/Boston Children’s.