Review question
We reviewed the evidence about the effect and safety of gene therapy on survival and on preventing symptoms and complications associated with sickle cell disease.
Background
Sickle cell disease results when a child inherits faulty genes for producing haemoglobin from both parents. It is a disease that is linked with frequent illness from early life and often results in death earlier than in the general population. Gene therapy replaces these faulty genes with normal ones.
Search date
The evidence is current to: 21 September 2020.
Key results
We looked for trials that used this approach of replacing faulty genes for producing haemoglobin with normal ones in the treatment of sickle cell disease. We found no trials to provide reliable evidence about the risks or benefits of gene therapy for this condition. There is a need for trials that assess the benefits or risks of gene therapy for sickle cell disease.
No randomised or quasi-randomised clinical trials of gene therapy for sickle cell disease were reported. Thus, no objective conclusions or recommendations in practice can be made on gene therapy for sickle cell disease. This systematic review has identified the need for well-designed, randomised controlled trials to assess the benefits and risks of gene therapy for sickle cell disease.
Sickle cell disease encompasses a group of genetic disorders characterized by the presence of at least one hemoglobin S (Hb S) allele, and a second abnormal allele that could allow abnormal haemoglobin polymerisation leading to a symptomatic disorder.
Autosomal recessive disorders (such as sickle cell disease) are good candidates for gene therapy because a normal phenotype can be restored in diseased cells with only a single normal copy of the mutant gene. This is an update of a previously published Cochrane Review.
The objectives of this review are:
- to determine whether gene therapy can improve survival and prevent symptoms and complications associated with sickle cell disease;
- to examine the risks of gene therapy against the potential long-term gain for people with sickle cell disease.
We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register, which comprises of references identified from comprehensive electronic database searches and searching relevant journals and abstract books of conference proceedings. We also searched online trial registries,
Date of the most recent search of the Group's Haemoglobinopathies Trials Register: 21 September 2020.
All randomised or quasi-randomised clinical trials (including any relevant phase 1, 2 or 3 trials) of gene therapy for all individuals with sickle cell disease, regardless of age or setting.
No trials of gene therapy for sickle cell disease were found.
No trials of gene therapy for sickle cell disease were reported.