FDA Experts to Vote on Safety of Sickle Cell Cure | ET REALITY


An estimated 100,000 people in the United States suffer from sickle cell anemia, most of whom are of African ancestry. Sickle cell anemia shortens life, damages organs and bones, and causes episodes of stabbing pain that can repeatedly send patients to emergency rooms or lead to long hospital stays.

A report from the Institute for Clinical and Economic Review saying that for people who do not have sickle cell disease, “it is difficult to understand the physical, emotional and mental toll.” People with the disease, the report adds, “not only described intense fatigue, anxiety and depression, but sometimes extreme hopelessness.”

One patient, Mariah Jacqueline Scott, 32, who lives in Highland Park, New Jersey, underwent two hip replacements, two shoulder replacements, a splenectomy, a gallbladder removal and a tonsillectomy due to the disease. She spent the year after her daughter was born in and out of the hospital receiving treatment for extreme pain caused by blocked blood vessels. She had her second shoulder replacement after her shoulder collapsed while she was holding her baby.

The only cure has been a bone marrow transplant, which requires finding a donor, undergoing intensive chemotherapy and taking immunosuppressive medications. But gene editing offers an alternative. Vertex and CRISPR Therapeutics, the creators of the treatment that the FDA committee accepted on Tuesday, said that in clinical trials, symptoms of the disease disappeared after patients received the treatment. So far, the patients appear to be cured. The technique activates a gene that can produce normally functioning blood cells.

Ms Scott said she knew gene editing was arduous but was seriously considering undergoing the treatment when it became available.

Vertex therapy begins when doctors extract stem cells from the blood and send them for treatment. Next comes intense chemotherapy to completely cleanse the bone marrow before injecting the treated cells. After that, patients must spend at least a month in a hospital while the treated cells repopulate the bone marrow.

Since each patient’s cells must be treated individually, there are questions about how quickly companies can ramp up production.

“Manufacturing is very complicated,” said Dr. Stephan Grupp, chief of the section of cell therapy and transplantation at Children’s Hospital of Philadelphia, who consults for Vertex.

The treatment will be extremely expensive, potentially millions of dollars per patient, and the companies will not say how many patients they expect to be able to treat at first.

Gene editing can also impose personal difficulties on patients and their families. A hospital with experience in managing patient treatment and care may be far from home. And patients must stay there for a long period of time.

If the advisory committee recommends the Vertex treatment, the FDA will decide whether to approve it on December 8.

On December 20, the FDA will decide on another sickle cell gene therapy application made by Bluebird Bio. Two other companies and one academic center, Boston Children’s Hospital, are testing their own sickle cell gene therapies.

While these therapies could reduce the suffering of sickle cell patients in the United States and other wealthy countries, their need is even greater in some developing countries like Nigeria. However, it will be difficult to export them to developing countries because the treatments are extremely expensive and can only be administered in hospitals where doctors have experience in a range of advanced techniques.

One company, Beam, is testing a way to perform gene editing that requires no more than a single infusion in a doctor’s office. Vertex has what it calls an “aspirational” approach that would offer gene editing in a pill.

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