Health officials are close to approving a treatment — the first of its kind — for tens of thousands of Americans suffering from a debilitating blood disorder.
Last month, a Food and Drug Administration (FDA) Advisory Committee said it would consider approving the gene-editing drug Casgevy to treat sickle cell anemia, a life-long, extremely painful disease that deforms blood cells.
The drug was recently approved in the UK to treat sickle cell anemia and transfusion-dependent β-thalassemia – a deficiency of red blood cells that leads to severe anaemia. It is expected to cost the British government about 1 million pounds ($1.25 million) per patient.
If the US committee recommends the drug for sickle cell anemia, the FDA will vote on approval in December.
Casgevy would give new hope to the 100,000 Americans with sickle cell anemia, which currently can only be cured by a bone marrow transplant.
Patients with sickle cell anemia, of which there are about 100,000 in the United States, do not properly produce hemoglobin – a substance in red blood cells that carries oxygen throughout the body. This causes their red blood cells to stiffen and form a crescent instead of a disk (see photo), which can cause them to die and get stuck in the blood vessels.
Casgevy, made by Boston-based Vertex Pharmaceuticals (pictured) and Switzerland-based Crispr Therapeutics, works by editing the defective HBB gene behind both diseases in a patient’s bone marrow stem cells, allowing the body to produce functioning hemoglobin.
A bone marrow transplant is a procedure in which healthy blood-forming stem cells are transplanted from a donor to replace the patient’s bone marrow that does not produce enough healthy cells.
Stem cells are the body’s “raw materials,” or cells that can develop into many different specialized cell types. They can be used to repair damaged tissue, and researchers believe stem cell therapies could one day treat diseases such as Alzheimer’s and paralysis.
In most bone marrow transplant cases, the donor is a sibling, but even a sibling has only a one in four chance of being a match for the patient. And often, transplants are not performed because of the risk that the transplanted cells will attack other cells in the recipient’s body, which can be life-threatening.
There are more than 30 FDA-approved gene therapies to treat different types of cancer and the blood disorder hemophilia. However, many are largely inaccessible due to high costs.
Last year, the US approved the gene-editing drug Hemgenix for hemophilia, a bleeding disorder in which the blood does not clot properly. The drug costs $3.5 million per dose, making it the most expensive drug in the world.
Casgevy is the first approved drug using the innovative gene-editing tool CRISPR, known as “genetic scissors”, which allows scientists to make precise changes to DNA. The inventors received the Nobel Prize in 2020.
The drug, made in Switzerland by Boston-based Vertex Pharmaceuticals and Crispr Therapeutics, modifies the defective HBB gene that causes sickle cell anemia in a patient’s bone marrow stem cells, allowing the body to produce properly functioning hemoglobin, the protein in red blood cells. produced which is responsible for the development of sickle cell anemia. Oxygenation of tissues throughout the body.
To do this, stem cells are taken from a patient’s bone marrow and processed in the laboratory with molecular “scissors” that specifically turn off the defective gene.
Stem cells are then re-injected into the patient, who may have to spend a month or more in the hospital while the treated cells begin to form healthy red blood cells.
Scientists believe that the results have the potential to last a lifetime.
An ongoing study of the drug shows that 97 percent of sickle cell patients were pain-free for at least a year after treatment.
Sickle cell anemia is the general term for a group of inherited diseases that severely affect red blood cells.
100,000 Americans and 15,000 Britons are affected, most of whom are black.
Healthy red blood cells—produced by stem cells in the bone marrow—are round, hollow discs that bend and bend easily.
However, in people with sickle cell disease, defective stem cells produce crescent-shaped red blood cells.
They are rigid, cannot enter smaller blood vessels, and are prone to blockages, depriving parts of the body of oxygen.
John James OBE, chief executive of the Sickle Cell Society of Britain, said: “Sickle cell anemia is an incredibly debilitating disease that causes sufferers significant pain and potentially leads to premature death.”
“There are currently limited medicines available to patients, so I welcome today’s news that a new treatment has been found to be safe and effective, with the potential to significantly improve the quality of life for so many people.”
Jimi Olaghere, 36, who lives in the Atlanta, Georgia, area, has suffered from sickle cell anemia since childhood and was hospitalized almost every month.
The tech entrepreneur told the BBC the condition felt like “pieces of glass running through your veins or someone hitting your joints with a hammer”.
“You wake up in the morning in pain and go to bed in pain.”
However, Mr Olaghere was one of the first patients to undergo the revolutionary new gene editing treatment in 2020 as part of Vertex Pharmaceuticals and Crispr Therapeutics’ clinical trials in the US.
He said he woke up without pain and it was “like a rebirth.”
“I look back and think, ‘Wow, I can’t believe I lived with that’.”
If the FDA panel recommends the treatment, the agency will decide on December 8 whether to approve it.
Source link
Crystal Leahy is an author and health journalist who writes for The Fashion Vibes. With a background in health and wellness, Crystal has a passion for helping people live their best lives through healthy habits and lifestyles.
