The life of Evie Junior was defined by pain. He was born with sickle cell disease, which makes red blood cells sticky and C-shaped, not smooth and round. These cells are believed to move freely through the blood vessels, carrying oxygen to the body. But in people with this inherited form of anemia, they clump together and block blood flow. This triggers excruciating episodes called pain attacks, which can occur anywhere in the body and last for hours or even weeks. The disease damages organs over time and can cause strokes and premature death.
People with sickle cell disease are often tired because their red blood cells die off quickly, cutting off oxygen to the body. Strenuous exercise, sudden changes in temperature, and dehydration can also trigger a pain attack. Growing up in the Bronx, New York, Junior remembers getting out of breath easily and having to be careful when playing sports or swimming. The pain was so bad that he often missed school.
As an adult, it couldn’t be easier. Sometimes he could stave off the pain with ibuprofen and return to work the next day. But every few months, a serious attack sent him to the hospital. Things got so bad that in 2019 he signed up for a clinical trial at the University of California, Los Angeles, which is testing gene therapy to cure sickle cell disease. It involves genetically modifying patients’ hematopoietic stem cells in the laboratory so that they can produce healthy red blood cells. The procedure is experimental. Junior knew there was a chance it wouldn’t work. “I felt like it was time for a Hail Mary,” he says. “My whole life up to that point was being sick.”
In July 2020, he received a one-time infusion of his own modified stem cells. Three months after treatment, tests showed that 70% of his blood cells showed the expected change, well above the threshold needed to eliminate symptoms. He hasn’t had a pain attack since. He can do more outdoor activities and he doesn’t have to worry about missing work. He plans to go skydiving soon, which he never imagined he would do before. “My quality of life is so much better now,” he says.
Junior, now 30, is one of dozens of sickle cell patients in the United States and Europe who have received gene therapies in clinical trials, some run by universities, others by biotechnology companies. Two of these therapies, one from Bluebird Bio and the other from Crispr Therapeutics and Vertex Pharmaceuticals, are closest to commercialization. Companies are now seeking regulatory approval in the United States and Europe. If successful, more patients could soon benefit from these therapies, although access and affordability could limit who receives them.
“I’m optimistic this will be a game-changer for these patients,” says Cheryl Mensah, a hematologist at Weill Cornell Medicine and New York-Presbyterian Hospital, who treats adults with sickle cell disease. “If more patients are on curative therapies, especially at younger ages, there will be fewer adults with chronic pain and fatigue.”
sickle cell disease affects approximately 100,000 people in the United States and millions worldwide. The vast majority are of African descent, but the disease also affects Hispanics from Central and South America and those of Middle Eastern, Asian, Indian and Mediterranean descent.