Biotech 5 November 2026 4 MIN READ
CRISPR in 2026: What Is Approved and What Is Not
What CRISPR medicine is approved today and what is not: Casgevy, its 2026 paediatric extension, a first in vivo decision due in March 2027 and one infant.
THE SHORT ANSWER
Only one CRISPR therapy is approved: Casgevy, for sickle cell disease and transfusion-dependent beta thalassaemia, in which the patient's own stem cells are edited outside the body. The FDA extended it to children aged 2 and over in July 2026. Editing inside the body is not approved yet.
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What CRISPR does in a medicine
The US Food and Drug Administration (FDA) describes CRISPR/Cas9 as a genome editing technology that can be directed to a specific spot in DNA, where it cuts the genetic material so that DNA can be removed, added or replaced. In medicine that sentence covers very different products, and the useful question is where the editing happens: in cells taken out of the body, or inside the patient.
What is approved: one therapy, edited outside the body
On 8 December 2023 the FDA approved Casgevy, the first FDA-approved therapy to use CRISPR/Cas9, for sickle cell disease in patients aged 12 and over with recurrent vaso-occlusive crises, the episodes of severe pain the disease causes. It was later approved for transfusion-dependent beta thalassaemia too.
The label describes how it works. The patient’s own blood stem cells are collected, then edited outside the body at an enhancer region of the BCL11A gene. That lowers the activity of BCL11A in red-blood-cell precursors and raises fetal haemoglobin, which stops red cells sickling in sickle cell disease and reduces the need for transfusions in thalassaemia. Before the edited cells go back, the patient receives myeloablative conditioning: a high-intensity treatment that clears the bone marrow, which the FDA’s 2023 announcement describes as high-dose chemotherapy. The label warns of failure of neutrophil engraftment, delayed platelet engraftment, hypersensitivity reactions and the risk of unintended edits elsewhere in the genome.
On 1 July 2026 the FDA extended the approval to patients aged 2 and over, 53 days after the filing. The evidence came from trials in children aged 5 to under 12: in sickle cell disease, all eight of the 11 treated patients who could be evaluated met the main outcome of no severe crises for at least 12 consecutive months; in thalassaemia, eight of nine evaluable patients out of 15 treated reached 12 months of transfusion independence, with a median of 20.1 months. For ages 2 to 4 the FDA granted extrapolation from those results, not a trial of its own.
Outside the United States the same therapy is spreading. The British regulator, the MHRA, has extended its approval to children from 5, The Pharmaceutical Journal reported on 2 November 2026. CRISPR Therapeutics, which developed it with Vertex, says in its own results release that it is approved in 39 countries, that more than 750 patients have started treatment worldwide and that third-quarter revenue was $99 million. Those are company figures.
What is not approved: editing inside the body
Casgevy edits cells in a laboratory. The next step is delivering the editor into the patient, and no such therapy is approved as of 5 November 2026. The nearest candidate is Intellia’s lonvoguran ziclumeran for hereditary angioedema. The company reports a phase 3 trial of 80 patients in which attacks fell 87% against placebo over six months, and 62% of treated patients were free of attacks and of other therapy, against 11% on placebo. The FDA has accepted its application with priority review and a decision date of 10 March 2027, according to the company and to FDAnews. If it is approved, the company says it would be the first in vivo CRISPR therapy.
A different kind of case is one infant’s. In The New England Journal of Medicine in May 2025, a team in Philadelphia described a base-editing therapy, a related technique, built for a single baby with a severe liver enzyme deficiency called CPS1 deficiency. The treatment travelled in fat nanoparticles and was given twice, at about 7 and 8 months of age. NIH says the approval process took six months from diagnosis to treatment. In the seven weeks after the first dose the infant could eat more protein and take half the starting dose of a nitrogen-scavenging drug. That is one patient and a short follow-up, so it shows the method can be built fast, not that it works for others.
What stays uncertain
The label itself lists off-target editing as a risk, and patients on the two approved gene therapies are being followed in a long-term study. Casgevy also needs the demanding conditioning treatment, and a one-time therapy is only as good as the years of follow-up behind it.
Our take: “CRISPR cures” is ahead of the evidence, but it is no longer a promise. Today the approved list is short: one therapy, for two blood diseases, built outside the body. The decision on 10 March 2027 will be the first public test of editing inside the body, and we will update this page when it comes.
Questions and answers
Is there an approved CRISPR treatment?
Yes, one: Casgevy, approved by the FDA in December 2023 for sickle cell disease and later for transfusion-dependent beta thalassaemia. Patients' own stem cells are edited outside the body and given back after strong chemotherapy.
Can CRISPR be used on children?
In the United States, Casgevy is approved from 2 years old since July 2026. The trials covered ages 5 to under 12, and the FDA extended the approval to ages 2 to 4 by extrapolation.
Is there a CRISPR therapy that edits genes inside the body?
Not approved yet. Intellia's lonvo-z for hereditary angioedema has an FDA decision date of 10 March 2027, and the company says it would be the first in vivo CRISPR therapy.
Was the baby treated with a custom gene editor cured?
The 2025 report describes one infant, who tolerated more dietary protein and half the starting dose of a drug after treatment. It is a single case with short follow-up, so it cannot show a cure.
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Sources
- FDA Approves First Gene Therapies to Treat Patients with Sickle Cell Disease (8 December 2023) · US Food and Drug Administration · Accessed
- FDA Approves First Gene Therapy for Young Children with Sickle Cell Disease (1 July 2026) · US Food and Drug Administration · Accessed
- CASGEVY prescribing information (revised July 2026) · US Food and Drug Administration · Accessed
- MHRA extends approval for gene-editing therapy to patients aged five years and over (2 November 2026) · The Pharmaceutical Journal · Accessed
- CRISPR Therapeutics Provides Business Update and Reports Third Quarter 2026 Financial Results (2 November 2026) · CRISPR Therapeutics (company press release) · Accessed
- Intellia Therapeutics Announces FDA Acceptance of Biologics License Application with Priority Review for Lonvoguran Ziclumeran (8 September 2026) · Intellia Therapeutics (company press release) · Accessed
- Intellia BLA Gets Priority Review for Hereditary Angioedema · FDAnews · Accessed
- Patient-Specific In Vivo Gene Editing to Treat a Rare Genetic Disease (Musunuru et al.), N Engl J Med 392, 2025 · New England Journal of Medicine · Accessed
- Infant with rare disease receives customized gene therapy · NIH Research Matters · Accessed
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