Swiss gene editing company CRISPR Therapeutics and US-based Vertex Pharmaceuticals have started treating patients in a Phase I/II clinical trial of an investigational gene-editing therapy CTX001 for the treatment of transfusion-dependent beta thalassemia (TDT).
CTX001 is an autologous, CRISPR/Cas9 gene-edited hematopoietic stem cell therapy being developed to help patients suffering from severe hemoglobinopathies.
The product is the first therapy under a research collaboration formed by CRISPR and Vertex in 2015 to use CRISPR/Cas9 for developing new treatments targeting underlying genetic causes of disease.
CTX001’s safety and efficacy will be assessed in patients aged 18-35 years with TDT, non-beta zero / beta zero subtypes as part of the open-label Phase I/II trial.
The trial will initially involve sequential treatment of two patients and will be opened for further concurrent enrolment based on the data obtained. It will take place at clinical sites across Canada and Europe.
A Phase I/II trial will also be conducted in the US and also include beta thalassemia patients.
CRISPR Therapeutics CEO Samarth Kulkarni said: “We have made tremendous progress with CTX001 and are pleased to announce that we’ve treated the first patient with beta thalassemia in this clinical study.
“Treating the first patient in this study marks an important scientific and medical milestone and the beginning of our efforts to fully realise the promise of CRISPR/Cas9 therapies as a new class of potentially transformative medicines to treat serious diseases.”
CTX001 is also being studied in a separate Phase I/II trial for severe sickle cell disease (SCD). This trial has commenced enrolment and treatment is expected to be initiated this year.
The trial will also assess the safety and efficacy of the product in severe SCD patients aged 18-35 years. Its design includes the initial treatment of two patients, followed by broader concurrent enrolment.
The trial is being conducted in the US, with plans to expand to Canada and Europe over the coming months.
During the trials, hematopoietic stem cells will be collected from peripheral blood, edited using the CRISPR/Cas9 technology and infused back into the patient via a stem cell transplant.
Patients will be monitored to establish when the edited cells start production of mature blood cells, as well as to assess the impact of CTX001 on various disease measures.