The FDA[1] has not approved a clinical trial request for CTX001, an experimental drug that uses CRISPR technology. This drug is ex-vivo[2] gene therapy which would be used as first-line treatment in the management of sickle cell anaemia[3]. It is being developed jointly by CRISPR Therapeutics and Vertex Pharmaceuticals. The first laboratory results have proved “promising”.
In 2016, China became the first country to carry out a clinical trial in humans using CRISPR-based treatment[4]. For CTX001, the next step is to conduct an early trial in adult volunteers but the FDA has “refused to approve the study” arguing “that a certain number of questions remain unanswered”. Brian Skorney, a biotechnologist in Wisconsin explains: “There’s so much promise with this technology, but it’s such early days. It’s a permanent alteration of a patient’s genetic code so I think the FDA is going to be cautious”.
Sickle cell anaemia is a genetic blood disorder in which the red blood cells are deformed. This has a harmful effect on carrying oxygen through the body and can cause numerous health problems, chronic pain, blindness and stroke, etc. CTX001 can modify the stem cells harvested from a patient to stimulate foetal haemoglobin. This will have a significant effect on subjects with sickle cell anaemia by reducing the symptoms of the disease.
See also:
Sickle cell anaemia: initial success for gene therapy
Curing beta thalassemia via CRISPR: has the time come to switch to human trials?
Genome editing: what is the status of human treatment projects?
[1] FDA, US Food and Drug Administration
[2] Ex-vivo therapy: therapy via which target cells are harvested from the body, treated in a laboratory and then returned to the body.
[3] CRISPR: a potential remedy for sickle cell anaemia?
[4] CRISPR and somatic gene therapy: an initial human clinical trial in China
Bionews, Christie Whitehouse (11/06/2018)