Hey guys!! This is crazy. I was on the phone with my dad talking about sickle cell anemia and he said, “Aren’t they getting closer to curing that with gene editing or something?” I say, “No, we are years away from curing anything with gene editing”. Then he says, “Are you sure? I thought they were making progress with CRISPR.” So I look it up….. And guess what???? SICKLE CELL ANEMIA HAS BEEN CURED!!!!!!!!!!!!!!!!!!!!! Back in December of 2023. This is amazing and so exciting. 

But also, why hasn’t this made Breaking News all over the world? Why didn’t I hear about this the moment it happened? As someone who works in healthcare, I should have known about this. The day after I had found out, I went to work and started asking my co-workers if they knew about the cure for sickle cell anemia. I asked nurses, nurse practitioners, and doctors. No one knew. 

Anyway, I am beyond excited that we now have a cure for Sickle Cell Disease. This cure is going to completely change lives. There is still a lot that we don’t know about these treatments. We don’t know about the long-term side effects and we don’t know how long the effects will last. 

These treatments are going to be very expensive and inaccessible to a lot of people at first. The pharmaceutical companies who created these treatments are currently negotiating with insurance companies. I have hopes that these prices will decrease as gene editing becomes more popular and other pharmaceutical companies will create treatments for Sickle Cell Disease. Competition tends to drive prices down on treatments. 

Medical centers across the United States are beginning to offer this treatment. At this point in time, these centers are pretty spaced out. As time goes on, more centers will offer this treatment and accessibility will increase. 

We still have a long journey ahead of us to eradicate Sickle Cell Disease from humanity, but we are on the right path. Read more to learn about the specific treatments and how they work.

• Two drugs approved on December 8, 2023 (FDA, 2023): Casgevy and Lyfgenia

• Casgevy was produced by Vertex Pharmaceuticals Inc.

• Had been approved by the UK in November of 2023

• Lyfgenia was produced by Bluebird Bio Inc. 

• Both treatments are made from the patient’s red blood cells

• They are both given as a one-time, single-dose infusion

• Prior to receiving these treatments, a patient must undergo high-dose chemotherapy (FDA, 2023). This kills bone marrow cells so that they can be replaced with the modified stem cells

• The patients who received these medications in the trial are part of a long-term study. They will be followed for 15 years (Reardon, 2023)

• These medications cost several million dollars. It is estimated that a lifetime of Sickle Cell Anemia can cost anywhere from $4-6 million dollars. This accounts for medications, doctor appointments, hospital visits, and complications that occur due to sickle cell disease. (Pagliarulo, 2023)

Casgevy

• This is the first FDA-approved therapy utilizing CRISPR/Cas9. It is a form of gene editing.

• Approved for individuals 12 years and older with re-occurrent vaso-occlusive crises

• CRISPR/Cas9 is directed to cut the DNA in targeted places and remove specific pieces of DNA in stem cells. These stem cells are then placed back into the patient where they attach and multiply within the bone marrow. They increase the production of fetal hemoglobin which prevents the sickling of red blood cells

• The chemotherapy can lead to infertility

• In the trial for Casgevy, there were 31 participants and 29 of the participants were free from vaso-occlusive crises for at least 12 months (FDA, 2023)

• This drug costs around $2.2 million 

Lyfgenia

• This is a cell-based gene therapy approved for individuals who are 12 years and older with re-occurrent vaso-occlusive crises. It uses a gene delivery vehicle called a lentiviral vector for genetic modification (FDA, 2023). The blood stem cells are genetically modified to produce a red blood cell that has a lower risk of sickling. The modified stem cells are then placed in the patient

• The chemotherapy can lead to infertility

• In the trial for Lyfgenia, there were 32 participants and 28 of the participants were free from vaso-occlusive crises for 18 months

• Hematologic malignancy (blood cancer) occurred in a few of the participants who took this drug (FDA, 2023)

• Patients who receive this drug will need lifelong monitoring for blood cancer

• This drug costs around $3.1 million

Who is offering these treatments?

• Specialized centers around the United States.

• City of Hope National Medical Center in Duarte, California

• Methodist Hospital in San Antonio, Texas

• Medical City Dallas Hospital in Dallas, Texas

• Children’s Hospital of New Orleans in New Orleans, Louisiana

• The Children’s Hospital at TriStar Centennial in Nashville, Tennessee

FDA. (2023, December 8). FDA approves first gene therapies to treat patients with sickle cell disease. U.S. Food and Drug Administration. https://www.fda.gov/news-events/press-announcements/fda-approves-first-gene-therapies-treat-patients-sickle-cell-disease 

Pagliarulo, N. (2023, December 8). Pricey new gene therapies for Sickle Cell Pose Access Test. BioPharma Dive. https://www.biopharmadive.com/news/crispr-sickle-cell-price-millions-gene-therapy-vertex-bluebird/702066/#:~:text=Casgevy%2C%20the%20first%20CRISPR%20therapy,is%20priced%20at%20%243.1%20million.&text=The%20first%20gene%20therapies%20for,years%2C%20if%20not%20a%20lifetime. 

Reardon, S. (2023, December 8). FDA approves first CRISPR gene editing treatment for sickle cell disease. Scientific American. https://www.scientificamerican.com/article/fda-approves-first-crispr-gene-editing-treatment-for-sickle-cell-disease/ 

Maakaron, J. E. (2023, December 12). Sickle cell disease (SCD) treatment & management. Approach Considerations, Hydroxyurea Therapy, Transfusion. https://emedicine.medscape.com/article/205926-treatment#d29