“A new type of bone marrow transplant can cure sickle cell disease with only half of the donor’s cell proteins matching, according to new clinical trial results published in the New England Journal of Medicine,” described in Axios:
The procedure would greatly expand the pool of potential donors, in addition to costing less than one-quarter of the price of innovative gene therapies for the condition that have earned Food and Drug Administration approval in recent years….Sickle cell anemia is…the most common inherited blood disorder. It affects about 100,000 people in the U.S. and 8 million people across the world.The disease changes the shape of red blood cells in a way that can block blood flow to the rest of the body. Sickle cell anemia is associated with extreme pain and other health complications including strokes and organ damage….The new transplant method uses bone marrow from “half-matched donors,” who have some but not all of the same cell proteins as the patient. Patients received low doses of chemotherapy and total body irradiation before the transplant, followed by other drugs for up to a year to prevent adverse reactions.
This transplant is very expensive: about $467,747 per patient. But that is still cheap compared to sickle cell gene therapies. The gene therapy Casgevy costs $2.2 million, while the sickle-cell therapy Lyfgenia costs a whopping $3.1 million. Over half of Americans with sickle cell disease are enrolled in taxpayer funded programs such as Medicaid or Children’s Health Insurance, and it is hard to figure out how states and the federal government can cover gene therapies without increasing government healthcare spending a lot.
Earlier, gene therapy ended the years of excruciating pain suffered by Kendric, a boy with sickle cell disease. His life was “punctuated by episodes of excruciating pain, requiring days in the hospital as doctors tried to control it. Sickle cell eroded his hip bones. It prevented him from riding a bike or playing soccer or even going outside when the temperature was below 55 degrees Fahrenheit because cold often brought on intense pain.” But sickle cell gene therapy is not easy: “The treatment is labor intensive, requiring patients to spend at least a month in the hospital…large medical centers said they could treat only 10 or fewer [patients] per year, and some say they can treat just five or six.”
NBC reported that sickle cell gene therapy’s approval came
a decade after the discovery of CRISPR technology for editing human DNA, representing a significant scientific advancement….Casgevy, co-developed by Vertex Pharmaceuticals and CRISPR Therapeutics, uses Nobel Prize-winning technology CRISPR to edit a person’s genes to treat disease. The treatment was approved by U.K. regulators last month….. Casgevy uses CRISPR to make an edit to a person’s DNA that turns on fetal hemoglobin, a protein that normally shuts off shortly after birth, to help red blood cells keep their healthy full-moon shape. In clinical trials, Casgevy eliminated pain crises in most patients. The FDA approved the treatment for people 12 years and older…
While the treatment itself is administered only once, the whole process takes months. Blood stem cells are extracted and isolated before being sent to Vertex’s lab, where they’re genetically modified. Once ready, patients receive chemotherapy for a few days to clear out the old cells and make room for the new ones. After the new cells are infused, recipients spend weeks in the hospital recovering. Vertex will take the lead on launching the drug and estimates about 16,000 people with severe cases of sickle cell will be eligible….Because the procedure is so complex, it will be limited to certain health facilities like academic medical centers. Nine health-care facilities are ready to start administering Casgevy, Vertex said in a release, with more facilities added in the coming weeks….
The FDA can take many years to approve new drugs and therapies. The FDA didn’t approve a home test for HIV until 24 years after it first received an application. According to an FDA advisory committee, the test held “the potential to prevent the transmission of more than 4,000 new HIV infections in its first year of use alone.” That means thousands of people likely got infected with AIDS as a result of the delay in approving it. At least a hundred thousand people died waiting years for the FDA to approve beta blockers.
