Versiti Blood Research Institute Articles
Making a Cure for Sickle Cell Disease More Accessible
Recent advances in research have made it easier for some patients with sickle cell disease to receive lifesaving bone marrow transplants.
Tia Wilson and her family have been deeply affected by sickle cell disease (SCD). Her brother, cousin and aunt all died from the disease, and Tia herself was diagnosed at 6 weeks old. At 3 years old, she was hospitalized after suffering a stroke and began receiving blood and platelet transfusions every four weeks.
Tia was lucky: In 2015, she received a bone marrow transplant from another of her brothers, curing her. But for many patients, bone marrow transplants either aren’t an option, or they cannot find a familial match. Currently, these patients are treated with one of four FDA-approved therapies, which come in pill, powder and injection form. These medications help to manage SCD symptoms and reduce the likelihood of severe complications. But none has the curative effect of a bone marrow transplant.
Advances in bone marrow transplants
In order to prepare patients for transplant, they are given high-intensity conditioning regimens of chemotherapy to clear out their current bone marrow and make space for the new one. “In the past, they typically did full conditioning regimens for children and found that patients over age 16 had increased toxicity,” said Versiti Blood Research Institute Senior Investigator and Senior Medical Director of Hematology Joshua Field, MD, MS.
This led investigators to research low-intensity conditioning regimens that would be less harmful to patients. “The idea with low-intensity conditioning is that you’re not wiping out the bone marrow; you’re basically giving someone else’s bone marrow while yours is still there,” Dr. Field said. But this, too, had its complications. “They started doing some low-intensity conditioning regimens in adults, but they had a high rate of graft failure.”
Over the last several years, research conducted at Johns Hopkins University and the National Institutes of Health (NIH) has paved the way for new methods of preventing graft failure. “Now, there are protocols that have been studied at the level of the NIH, where there’s a high chance of success and a low rate of graft failure,” Dr. Field said.
Challenges with bone marrow transplantation in diverse communities
So, with new therapies available, why aren’t more SCD patients cured with bone marrow transplants? First, bone marrow transplants are risky. “Any time you undergo a bone marrow or stem cell transplant, there’s a 10% chance of mortality,” Dr. Field said. Because of the availability of other treatment options, and because a bone marrow transplant may not be the best option for every patient, many choose a treatment approach that manages their symptoms, rather than cures the disease altogether.
Second, “Just as it’s hard to find African American blood donors, it’s hard to find matched, unrelated donor transplants for African Americans, including patients with sickle cell disease,” Dr. Field said. In the past, patients needed a matched sibling in order to receive a bone marrow transplant; however, advances in technology and testing have enabled parents, as well as siblings, to donate bone marrow. “This has made it feasible for our patients to find donors and get transplants,” Dr. Field said.
Providing exemplary care for sickle cell patients
Still, bone marrow transplants aren’t always right for every SCD patient—nor are they considered a last-ditch treatment option. “We look for patients who are sick, but not too sick,” Dr. Field said. “We choose patients who are on the younger side who have had some complications with their sickle cell disease who have been on different therapies, but there is still room for improvement.”
In fact, two SCD patients who were treated at the Adult Sickle Cell Clinic at Froedtert Hospital in Wisconsin recently received curative bone marrow transplants from parent donors. “We’re one of a few centers doing transplants. Now, we have two patients who are cured,” Dr. Field said. “It’s really exciting.”
“We have a well-supported clinic by the hospital, and we’ve been successful in making therapies available to patients,” he added. “Our patients have access to very good care, and there isn’t better care that they don’t have access to. We don’t have many limitations in what we can do to provide outstanding care to sickle cell patients.”
Help ensure the health of patients with sickle cell disease by donating blood or joining the Be The Match national bone marrow/stem cell donor registry.
About the expert: Joshua Field, MD, MS, is the senior medical director of hematology at Versiti and a senior investigator at Versiti Blood Research Institute.