“It is a very serious disease with serious complications from which patients die relatively young,” says hematologist Linet Njue, senior physician at Inselspital Bern. According to the doctor, around 100 patients with the disease are being treated in large university hospitals in Switzerland, but the exact number is not recorded. It is one of the most common hereditary diseases worldwide.
The disease is caused by a gene that carries the blueprint for the red blood pigment haemoglobin. A gene mutation crystallizes the hemoglobin, causing the normally round red blood cells to deform into sickles. These, in turn, clog the bloodstream.
Now, the UK Medicines Agency has given the green light for a new gene therapy for sickle cell anaemia patients aged 12 and over. It is called Exacel (brand name “Casgevy”) and was developed by the companies Vertex Pharmaceuticals and CRISPR Therapeutics, the latter based in Zug.
It is the first ever approved treatment based on the CRISPR/Cas9 gene scissors. This is the technology that can precisely cut through and modify the genetic material and for the discovery of which the Nobel Prize in Chemistry was awarded in 2020.
No need for a foreign donor anymore
Victoria Gray, now 37, was the first person to be treated with the therapy in 2019. Thanks to the new “supercells”, her life has changed completely, she recently said. She now lives free of pain, can go back to work and take care of her four children.
Exacel has now been tested on around forty sickle cell anemia patients. As Vertex Pharmaceuticals and CRISPR Therapeutics have announced, additional clinical trials with children between the ages of 2 and 11 are now to begin. An application for approval for the therapy has not yet been received from the companies in Switzerland, as Swissmedic confirmed on request.
How Exacel Therapy WorksExacel does not target the disease-causing and mutated HBB gene, which causes the sickle-shaped blood cells. Rather, the therapy is dedicated to the gene called BCL11A. This gene is activated at birth and thus inhibits the formation of haemoglobin, which is actually only produced in the fetus. Exacel then cuts BCL11A apart, which deactivates the gene again and resumes prenatal hemoglobin production. This provides additional hemoglobin that is not malformed. The symptoms of the disease disappear. (sny)
Jacob Corn is Professor of Genome Biology at ETH Zurich and has been working on CRISPR treatments for years, including for sickle cell disease. “The whole CRISPR community is in a frenzy. The Exacel successes are impressive,” he says.
Nevertheless, it is crucial to accompany the treated patients over a long period of time, the regulatory authorities require at least 15 years. This is the only way to rule out long-term side effects, such as an increased risk of blood cancer – a concern that worries some scientists. However, Corn emphasizes: “At the moment, things are looking really good.”
According to the ETH professor, the CRISPR gene scissors offer a gateway to a new world of medicine. He draws a comparison:
It’s the same with hereditary diseases so far: You can make a genetic diagnosis to suffering patients, but you can’t offer them a therapy – that’s changing now.
There are more than 7000,1 diseases that are based on a single gene mutation, such as sickle cell anemia, and dozens of therapies are already in the pipeline, for example against the metabolic disease called familial hypercholesterolemia, which affects about 200 in <> people in Switzerland.
Due to the disease, a dangerous amount of cholesterol always remains in the blood. This greatly increases the risk of a heart attack or stroke. Studies with the CRISPR therapy from the biotech company Verve Therapeutics have so far been promising, even suggesting that “the world’s biggest killer” can soon be stopped, according to the headline of the US magazine “MIT Technology Review”.
Targeting multiple genes is much more difficult
Other diseases in the focus of the genetic engineers are cystic fibrosis, Duchenne muscular dystrophy or progeria, in which affected children age as if in fast motion. In addition to these single-mutation diseases, there are countless other diseases that are based on a combination of several gene mutations and environmental factors: Alzheimer’s, arthritis, many cancers, diabetes, autism spectrum disorders are just a few examples.
Another hurdle of future CRISPR therapies is those diseases that affect organs that are difficult to reach. In sickle cell anemia, it is comparatively easy to extract the blood cells from the body, manipulate them and return them. “In cystic fibrosis, on the other hand, where the lungs are damaged, it is a much more difficult procedure to get the genetic medicine to the right place,” says Corn.
The high cost could limit availability
Geneticists are very worried about the horrendous costs, which are estimated to run into the millions for a single CRISPR treatment. It is questionable whether poorer countries can afford such therapies. Even rich countries get into trouble when a large number of patients suddenly want to be treated.
One dilemma, according to Jacob Corn, is that the safety requirements imposed by the health authorities are enormously high – and therefore costly. “That’s good, because it must be guaranteed that the therapies do no more harm than good.” The hope is that after the first approvals, the multitude of safety and efficacy tests will no longer have to be carried out every single time. “If the safety of CRISPR technology is proven on its own, then hopefully it would be legitimate to accelerate the testing and approval of therapies for other diseases,” says Corn.
Another approach: Instead of isolating the cells for the gene changes, treating them and then injecting them back into the body, researchers are tinkering with a gene injection: “The idea is that the genome editing process is injected into the body, so to speak, where it finds the right place and exerts its effect.” This would not only make treatment cheaper, but also more accessible, for example in regions of Africa where there are few health facilities. No tests have yet been carried out in humans, only in animals.
But Jacob Corn is confident: “A large number of research groups around the world are involved in CRISPR. How quickly things can sometimes happen when many bright minds are working on a problem at the same time was seen with the Corona vaccination.” (aargauerzeitung.ch)

News
The CDC buried a measles forecast that stressed the need for vaccinations
This story was originally published on ProPublica, a nonprofit newsroom that investigates abuses of power. Sign up to receive our biggest stories as soon as they’re published. ProPublica — Leaders at the Centers for Disease Control and Prevention [...]
Light-Driven Plasmonic Microrobots for Nanoparticle Manipulation
A recent study published in Nature Communications presents a new microrobotic platform designed to improve the precision and versatility of nanoparticle manipulation using light. Led by Jin Qin and colleagues, the research addresses limitations in traditional [...]
Cancer’s “Master Switch” Blocked for Good in Landmark Study
Researchers discovered peptides that permanently block a key cancer protein once thought untreatable, using a new screening method to test their effectiveness inside cells. For the first time, scientists have identified promising drug candidates [...]
AI self-cloning claims: A new frontier or a looming threat?
Chinese scientists claim that some AI models can replicate themselves and protect against shutdown. Has artificial intelligence crossed the so-called red line? Chinese researchers have published two reports on arXiv claiming that some artificial [...]
New Drug Turns Human Blood Into Mosquito-Killing Weapon
Nitisinone, a drug for rare diseases, kills mosquitoes when present in human blood and may become a new tool to fight malaria, offering longer-lasting, environmentally safer effects than ivermectin. Controlling mosquito populations is a [...]
DNA Microscopy Creates 3D Maps of Life From the Inside Out
What if you could take a picture of every gene inside a living organism—not with light, but with DNA itself? Scientists at the University of Chicago have pioneered a revolutionary imaging technique called volumetric DNA microscopy. It builds [...]
Scientists Just Captured the Stunning Process That Shapes Chromosomes
Scientists at EMBL have captured how human chromosomes fold into their signature rod shape during cell division, using a groundbreaking method called LoopTrace. By observing overlapping DNA loops forming in high resolution, they revealed that large [...]
Bird Flu Virus Is Mutating Fast – Scientists Say Our Vaccines May Not Be Enough
H5N1 influenza is evolving rapidly, weakening the effectiveness of existing antibodies and increasing its potential threat to humans. Scientists at UNC Charlotte and MIT used high-performance computational modeling to analyze thousands of viral protein-antibody interactions, revealing [...]
Revolutionary Cancer Vaccine Targets All Solid Tumors
The method triggers immune responses that inhibit melanoma, triple-negative breast cancer, lung carcinoma, and ovarian cancer. Cancer treatment vaccines have been in development since 2010, when the first was approved for prostate cancer, followed [...]
Scientists Uncover Hidden Protein Driving Autoimmune Attacks
Scientists have uncovered a critical piece of the puzzle in autoimmune diseases: a protein that helps release immune response molecules. By studying an ultra-rare condition, researchers identified ArfGAP2 as a key player in immune [...]
Mediterranean neutrino observatory sets new limits on quantum gravity
Quantum gravity is the missing link between general relativity and quantum mechanics, the yet-to-be-discovered key to a unified theory capable of explaining both the infinitely large and the infinitely small. The solution to this [...]
Challenging Previous Beliefs: Japanese Scientists Discover Hidden Protector of Heart
A Japanese research team found that the oxidized form of glutathione (GSSG) may protect heart tissue by modifying a key protein, potentially offering a novel therapeutic approach for ischemic heart failure. A new study [...]
Millions May Have Long COVID – So Why Can’t They Get Diagnosed?
Millions of people in England may be living with Long Covid without even realizing it. A large-scale analysis found that nearly 10% suspect they might have the condition but remain uncertain, often due to [...]
Researchers Reveal What Happens to Your Brain When You Don’t Get Enough Sleep
What if poor sleep was doing more than just making you tired? Researchers have discovered that disrupted sleep in older adults interferes with the brain’s ability to clean out waste, leading to memory problems [...]
How to prevent chronic inflammation from zombie-like cells that accumulate with age
In humans and other multicellular organisms, cells multiply. This defining feature allows embryos to grow into adulthood, and enables the healing of the many bumps, bruises and scrapes along the way. Certain factors can [...]
Breakthrough for long Covid patients who lost sense of smell
A breakthrough nasal surgery has restored the sense of smell for a dozen long Covid patients. Experts at University College London Hospitals NHS Foundation Trust successfully employed a technique typically used for correcting blocked nasal passages, [...]