The U.S. greenlights the first gene-editing therapy, Casgevy, for the treatment of sickle cell disease.

• The first gene-editing treatment to be marketed in the U.S. has been approved by the Food and Drug Administration.
• CRISPR technology, which has won a Nobel Prize, is used by Casgevy to treat sickle cell disease, a blood disorder that affects approximately 100,000 Americans.
• The one-time treatment developed by Vertex Pharmaceuticals and CRISPR Therapeutics will cost $2.2 million per patient.

On Friday, the U.S. Food and Drug Administration approved Casgevy, the first gene-editing treatment in the country, for use in patients with sickle cell disease. This approval marks a significant scientific advancement, coming a decade after the discovery of CRISPR technology for editing human DNA. However, reaching the tens of thousands of people who could benefit from the treatment may be challenging due to the potential hurdles, such as the high cost of administering the complex therapy at $2.2 million per patient.

CRISPR gene editing technology developed by Casgevy, in collaboration with , has been approved by U.K. regulators to treat disease.

On Friday, Vertex's shares dropped by 1%, while CRISPR's shares plummeted by 8%.

An inherited blood disorder called sickle cell causes red blood cells to become misshapen half moons that get stuck inside blood vessels, restricting blood flow and causing pain crises. Approximately 100,000 Americans are estimated to have the disease.

Casgevy utilizes CRISPR technology to activate fetal hemoglobin, a protein that typically deactivates following birth, in order to maintain the shape of red blood cells. Clinical trials have demonstrated that Casgevy effectively alleviates pain crises in the majority of patients.

The FDA approved the treatment for people 12 years and older.

Dr. Nicole Verdun, director of the Office of Therapeutic Products within the FDA's Center for Biologics Evaluation and Research, stated that sickle cell disease is a rare, debilitating, and life-threatening blood disorder with significant unmet need, and they are thrilled to advance the field, particularly for individuals whose lives have been severely impacted by the disease.

Verdun stated that gene therapy offers the potential for more precise and efficient treatments, particularly for those with rare diseases where existing treatment options are scarce.

The process of receiving genetically modified blood stem cells from Vertex takes months, even though the treatment itself is only given once. First, blood stem cells are extracted and isolated before being sent to the lab for modification. After that, patients undergo chemotherapy for a few days to clear out old cells and make way for the new ones. Finally, recipients spend weeks in the hospital recovering after the new cells are infused.

The company, Vertex, will spearhead the launch of the drug and anticipates that approximately 16,000 individuals with severe cases of sickle cell will be eligible.

Analysts are concerned that even among those who could benefit the most, few will seek out a treatment that takes months to complete, poses the risk of infertility, and may be cost-prohibitive. Vertex announced in a regulatory filing on Friday that the treatment will cost $2.2 million per patient.

Dr. Reshma Kewalramani, CEO of Vertex, stated on Friday in an interview with CNBC that the company believes the cost of medicine should reflect its value, which is a one-time therapy that could provide a lifetime of cure.

Kewalramani stated that payers, patients, and physicians are showing "unanimous enthusiasm" towards Vertex because people with sickle cell have been marginalized, and the field hasn't seen much innovation.

Nine academic medical centers are set to begin administering Casgevy, with more facilities to follow in the near future, according to Vertex.

Bluebird’s Lyfgenia

On Friday, the FDA approved a separate gene therapy by Bluebird Bio, called Lyfgenia, which works differently than Casgevy but is administered similarly and is intended to eliminate pain crises. This therapy was also approved for the treatment of sickle cell disease in people 12 years and older.

The market value of Lyfgenia, which is $300 million, fell 40% Friday, despite the company's decision to charge $3.1 million per patient for its product.

Nearly 20,000 patients will be eligible for treatment with the two therapies approved by the FDA's Center for Biologics Evaluation and Research, according to Dr. Peter Marks.

The FDA issued a black-box warning for Bluebird Bio's Lyfgenia, stating that it can cause rare blood cancers in some cases.

The FDA issued a warning about Lyfgenia after two patients in a clinical trial died from leukemia, according to Verdun, who spoke to reporters on Friday.

It is uncertain whether the cancer was caused by Lyfgenia or another aspect of the treatment process, such as chemotherapy.

Marks stated that the FDA emphasizes the importance of patients being informed about all possible side effects of the entire treatment regimen: "The focus is on the comprehensive therapy provided."

Verdun pointed out that Vertex did not receive a black-box warning on its label because it did not encounter similar blood cancer cases in its clinical trial.

Both Bluebird Bio and Vertex will track patients who receive their treatments for 15 years as part of a post-approval study, with the FDA urging them to closely monitor for malignancies.