World’s First Crispr Drug Takes Slow Start

Deshawn “DJ” Chow he waited a year to receive a treatment that could change his life. The 19-year-old was born with sickle cell disease, which makes red blood cells crescent-shaped and sticky. Abnormal cells accumulate and block blood vessels, cutting off oxygen to parts of the body and causing episodes of excruciating pain. The condition affects about 100,000 people in the United States, most of whom are black.

The pain came more and more frequently for Chow in high school, often landing him in the hospital. He avoided school, birthday parties, and sleepovers with friends. Sometimes the pain lasted for days. “It’s like my body is on fire,” she says.

A year ago, he learned about a new treatment called Casgevy that could end his years-long struggle with pain. This first approved drug using Nobel Prize-winning technology known as Crispr, a type of gene editing. Chow received Casgevy on December 5 at the City of Hope Cancer Center in Los Angeles. He is one of the first patients to receive treatment in the United States Since its approval in December 2023. It was also approved for beta thalassemia, a related blood disorder, in January this year.

Due to manufacturing complexity, insurance delays, and extensive patient preparation, few people have been dosed with Casgevy since its commercial launch in the United States. The slow rollout underscores the complex nature of commercializing cutting-edge medical treatments and delivering them to patients. Another genetic treatment for sickle cell, Lyfgenia, was approved last December and the first patient was treated in September. Developed by Bluebird Bio, it uses an old technology that introduces a new gene to treat the disease.

Vertex Pharmaceuticals and Crispr Therapeutics, which developed Casgevy, have not publicly disclosed how many patients have received the therapy so far. WIRED reached out to everyone 34 US hospitals have approved it until December. Of the 26 that responded, only City of Hope and Children’s National Hospital in Washington said they operated Casgevy. (Three hospitals declined to comment, and five others did not respond to multiple requests.) Chow is City of Hope’s first sickle cell patient, while a beta thalassemia patient is being treated at Children’s National. Several authorized centers told WIRED they will begin Casgevy infusions in early 2025.

“The process of getting this drug is very different from just taking a pill,” said Leo Wang, a hematologist-oncologist at Chow in Hope City. It is a one-time therapy that involves harvesting and editing human stem cells. For the patient, this means a tough cycle of chemotherapy and then a month in the hospital before getting the cells.