June 19th, 2025

1.5 years after approval, access to sickle cell therapies slowly spreads

Advocates say barriers have made uptake slow, but treatments bring hope

Avery Bleichfeld

For Taina Maitre, sickle cell disease has meant frequent pain and missed opportunities.

Last winter, she was in the hospital for Thanksgiving. And for Christmas. And again, for New Years.

And when Maitre, a 36-year-old nurse from Woburn, goes to the beach with friends, as the rest go in the ocean, she stays behind, worried the cold water will cause a sickle cell crisis.

“I can go to the beach,” she said, “but when everyone’s swimming, I’m back on the sand.”

Those crises, she said, have been getting worse over the past decade. In her four years of high school, Maitre said she was hospitalized for a sickle cell crisis maybe once. Now she’s admitted to the hospital for three- or four-week stints at a time, every month or two.

So, when she got the opportunity to get one of the two gene therapies designed to treat the disease, which were approved by the U.S. Food and Drug Administration at the end of 2023, she knew it was something she wanted to try.

“It’s just been hard, and it seems like it’s just getting harder with my crises,” she said. “So, the second it was offered to me, I was ready to just jump all in.”

Now, as Maitre prepares to start the lengthy treatment process, she said she is “really excited” for the relief she expects the treatment to bring.

At the end of July, she will have the first procedure to remove the stem cells that will be edited to treat her sickle cell disease, kicking off a process that can take up to about a year.

Gone, she expects, will be the days of missing family events, or hoping a sickle cell crisis won’t pull her away from a friend’s wedding or planning trips based on where the nearest hospital is.

“There’s just lots of things, mental capacity that sickle cell takes that I won’t have to do anymore,” Maitre said. “And of course, just feeling better — I’m going to feel better all the time, and not just some of the time.”

At the end of 2023, the FDA announced its approval of the two new gene therapies, the first two ever approved in the United States to treat sickle cell, from Vertex Pharmaceuticals and Bluebird Bio, both Boston area companies.

The disease overwhelmingly affects patients of color — especially in the Black community. According to the U.S. Centers for Disease Control, sickle cell disease impacts an estimated 100,000 people in the United States. More than 90% are Black.

At the time of their approval, there were 32 gene therapies already approved by the FDA, with the first approved in 2017. In the year-and-a-half since, another 11 have been added.

Bluebird Bio’s Lyfgenia works by adding working copies of the gene that produces hemoglobin — the protein in red blood cells that can clump together to cause sickling — to the removed blood stem cells. Those cells are then infused back into the body to make it produce functional adult hemoglobin.

Vertex’s Casgevy, the treatment Maitre is slated to receive at Mass General Hospital, was the first treatment approved by the FDA to use CRISPR technology, a gene editing technique. Through the treatment, doctors remove blood stem cells from a patient. Those cells are treated using CRISPR-Cas9 to make the body produce more fetal hemoglobin, which carries oxygen when a baby is growing in the womb and which generally isn’t affected by the sickling that can clog blood vessels.

At the time, experts hailed it as a major step forward in treating the disease, though some expressed questions and potential concerns around the cost and lengthy process that the treatments would require.

Now advocates say barriers around the procedure and the perception of it has slowed uptake of the two gene therapy treatments, but that they are “still excited” about getting them on the market, said Jacqueline Haley, executive director of the Massachusetts Sickle Cell Association.

Those concerns include the price point for the treatment. Vertex’s Casgevy treatment was initially priced at $2.2 million per patient and Bluebird Bio’s Lyfgenia was initially listed at $3.1 million; meanwhile half of the patients the Massachusetts Sickle Cell Association works with are on Medicaid, Haley said.

According to Vertex Pharmaceuticals in an earnings call from the first quarter of 2025, nationwide, Medicaid represents 45% of patients for its sickle cell gene therapy treatments. Vertex shared the transcript in response to a request for comment. Bluebird Bio didn’t respond to a request for comment.

Also of concern was fertility preservation for patients. The chemotherapy treatments involved in the procedure can affect patients’ ability to have children later.

Haley said that there have been some steps forward to reducing those barriers to uptake.

Last year, the State House passed a law that requires commercial insurance providers to offer wider coverage of fertility preservation measures, including for patients with sickle cell disease.

“It will allow for patients who have commercial insurance to be able to at least have the option to be able to plan for a family while they pursue getting these treatments,” Haley said.

This year, the group is lobbying for a similar measure for MassHealth patients, she said.

Maitre, who doesn’t have kids but wants them, said that fertility preservation had been on her mind for a while. Pursuing gene therapy has added a timeline to that.

But her pending treatment has also meant new hope for what that family could look like. As her sickle cell crises have gotten worse, Maitre said she realized that’s not how she wanted to have a family.

“They say takes a village — and I have a great village; my friends and family are the most amazing people, and if I had kids, it would be totally fine — but with that emotional toll that it takes on you, I know if I was in the hospital for months at a time, I wouldn’t be okay with that and then having kids at home,” she said.

When it comes to cost, many insurance providers offer some level of coverage for the treatments, though they may require doctors to submit a request for the treatment before it’s administered. Currently, MassHealth covers both treatments with prior authorization.

Maitre said that, for her, the “stars aligned” and her insurance will cover most if not all of her treatment.

But still, Haley said, those concerns, alongside general trepidation about a brand-new treatment, have led to some hesitation among the Massachusetts sickle cell community.

“While they are interested to know more about it, there’s also the delay or hesitation in seeking out this treatment,” Haley said. “We don’t know what the long-term effects are.”

In the earnings call, Stuart Arbuckle, chief operating officer at Vertex, said the rollout of the treatment is “progressing as we expected and gathering momentum across all regions.” As of that call, there were 65 hospitals “activated” to provide the treatment — locally, those centers comprise Boston Medical Center, Mass General Hospital, Boston Children’s Hospital and the Dana-Farber Brigham Cancer Center.

BMC and Boston Children’s Hospital are also qualified to provide Bluebird Bio’s treatment.

At the recommendation of the FDA, both Vertex and Bluebird Bio have agreed to report a 15-year follow-up of patients to track long-term effects of the treatment.

And Maitre said that, for her, the benefits of the treatment outweigh any potential for long-term effects.

“I always joke, if in 40 years something weird happens and I grow a tail or something crazy, that’s okay,” she said. “I got 40 years of my life that I got to experience life to the 100% fullest.”

Having that sense of “full freedom” on the horizon is important for her, Maitre said.

“Sickle cell has taken a lot from us,” she said. “Memories and all these events and all the things you’re missing — just regular life stuff on a Tuesday that you’re admitted for or at home not feeling good. If you got this treatment, and you got 20, 30, 40 years of your life back where every day you got to experience life and not be in the hospital? I would take that.”