New medical treatments will use genetic scissors, and other clever tricks

New medicines to treat sickle-cell disease and beta thalassaemia, two genetic blood disorders, will make headlines in 2024. Most notable of these is the first CRISPR-gene-edited drug, which made its historic arrival in late 2023. Gene editing uses molecular scissors to edit DNA. It is a more precise form of modification than gene therapy, an older technology that uses a viral vector to inject a working gene into a cell. Gene editing has moved astonishingly quickly through drug pipelines—much faster than gene therapies, which have been slow and difficult to develop.

For sickle-cell disease, the gene-edited therapy, exa-cel, developed by Crispr Therapeutics and Vertex, is likely to be approved just ahead of a gene-therapy drug from Bluebird Bio, lovo-cel. In both cases, stem cells are first extracted from a patient’s body. They are then either edited (exa-cel) or transfected with the viral vector (lovo-cel), and returned to the body, where they correct the genetic defect. The effects are said to last a lifetime.

But these drugs will cost more than $2m per patient. Even in America some patients will struggle to get hold of them. In poorer countries, where most patients with sickle-cell disease live, they will be impossible to obtain.

The great flexibility of the gene-editing technology, and its ability to target non-genetic diseases, means it has a particularly bright future. The coming year will see progress in efforts by Crispr Therapeutics and Caribou Biosciences to develop off-the-shelf cell products that can treat cancer and other diseases.

The workhorse of the immune system, the T-cell, can be gathered from donors and reprogrammed, via gene editing, to fight cancer without triggering an immune rejection by the patient’s body. This approach means that powerful CAR-T treatments no longer have to be manufactured individually, and expensively, for each patient.

Crispr Therapeutics is developing similar technology to create replacement insulin-producing cells in the pancreas. There are also efforts to develop “in vivo” gene editing, to allow gene-editing treatments to be delivered into the body by packaging them in lipid nanoparticles.

Gene-editing technology is advancing in other ways, too. Verve Therapeutics is focusing on cardiovascular disease using a more precise approach to gene editing known as “base editing”, which can change a single base in the genome without damaging the DNA molecule itself. Look for news of its early-stage work, on a treatment to lower cholesterol levels. Meanwhile another treatment, EBT-101 from Excision, which aims to use gene editing to eliminate HIV infection from the body, will complete enrolment of patients for its first phase-1 trial in 2024.

Other coming highlights in the year ahead include a hotly anticipated decision on a new antibiotic for urinary-tract infections, many of which are resistant to existing antibiotics; two “pentavalent” meningococcal vaccines that protect against a wide range of serotypes of meningitis; and an innovative “microinvasive” eye implant that continuously releases minuscule amounts of a drug for glaucoma, an eye disease. It promises to deliver far better results than eye drops, which patients often forget to apply regularly. Yet another exciting new treatment to keep an eye on, you might say, in the coming year. ■

Natasha Loder, Health editor, The Economist