Medical experts have hailed a high-tech gene therapy treatment for sickle cell disease that has been used in the Gulf region for the first time.
Sickle cell disease is an inherited blood disorder that can cause blood flow blockages and lead to problems such as joint pain, anaemia and, in later life, strokes.
Bahrain has become the only country outside the US to use a therapy called Casgevy, which involves gene-editing the patient’s cells. While expensive, the treatment offers the prospect of a lifelong cure for the disease, which is most common among people from Africa, India, the Caribbean, the Middle East and the Mediterranean, according to the US National Library of Medicine.
“It [Casgevy] is very significant,” Dr Maria Berghs, of the School of Allied Health Sciences at De Montfort University Leicester in the UK, told The National. “You cannot overstate the significance for patients in terms of giving them hope. For over 20 years there was literally nothing.”
Dr Tedros Adhanom Ghebreyesus, director general of the World Health Organisation (WHO), congratulated Bahrain in a post on X on Monday. “Thank you for your continued investment in science to ensure all people in Bahrain have the best possible care and to help the world advance medical treatment,” he said. “WHO is ready to work with all countries to anticipate scientific breakthroughs and hence speed up equitable access to innovation, safe and effective treatments.”
This week, Salman bin Hamad Al Khalifa, Bahrain's Crown Prince, visited the Bone Marrow and Stem Cell Transplant Unit at the Royal Medical Services Bahrain Oncology Centre, to meet the first sickle cell disease patient outside the US to complete treatment with Casgevy.
What is sickle cell disease and how does Casgevy work?
With sickle cell disease (SCD) a defective form of a gene, when inherited from both parents, causes individuals to produce an abnormal type of the blood protein haemoglobin. As a result, the red blood cells, which carry oxygen, are shaped like sickles and these restrict blood flow. Patients may be tired and short of breath because of anaemia, and vulnerable to infections. In later life, the disease can increase the risk of strokes.
The gene-editing treatment, only suitable for people aged 12 or above, involves extracting a patient’s stem cells from their bone marrow and modifying them using technology called Crispr-Cas9 to deactivate a gene called BCL11A. Once the patient has received conditioning chemotherapy, the edited cells are transplanted back into them.
BCL11A is not the gene that codes for haemoglobin, but does, after birth, instruct the body to make less foetal haemoglobin, which carries oxygen in the blood of developing foetuses, and to replace it with adult haemoglobin. In people with faulty haemoglobin genes, this switchover causes sickle cell disease symptoms to intensify, typically during childhood.
If BCL11A is deactivated, the body will produce more foetal haemoglobin, so red blood cells are shaped normally and blood flow is not restricted, offering a "functional cure".
The significance of Crispr-Cas9 “genetic scissors” technology, now widely used in biotechnology and not just in medicine, is such that its discoverers, Emmanuelle Charpentier and Jennifer Doudna, won the 2020 Nobel Prize in Chemistry.
In December 2023, Bahrain became the first country to approve Casgevy to treat SCD, with US authorities following about a week later. It was then approved in Saudi Arabia in January 2024, and in the UAE in December 2024. The UAE has pioneered a related technology; Al Jalila Children's Specialty Hospital in Dubai has for several years treated spinal muscular atrophy using a type of gene therapy in which the faulty gene is replaced with a normal gene.
In a statement announcing the use of Casgevy, Dr Jaleela bint Al Sayed Jawad Hasan, Bahrain’s Minister of Health, said her country was positioning itself as “a hub for innovative medical care”. She added: “This milestone exemplifies Bahrain’s commitment to integrating global medical innovations into our national healthcare strategy.”
Revolution in care
Casgevy was administered by the Bahrain Oncology Centre, which last year received accreditation from Vertex for its bone marrow transplant and cellular therapy services. Bahraini authorities said the centre can provide the treatment to patients from all over the world.
“As the clinical team responsible for delivering this groundbreaking treatment, we are honoured to bring Crispr-based therapy to patients in Bahrain and beyond,” said Dr Edward Rowland, chief executive of the Bahrain Oncology Centre. “Our success reflects the Bahrain Oncology Centre’s dedication to combining advanced technology with world-class expertise.”
Without gene-editing treatments, some SCD patients have to undergo regular blood transfusions if symptoms are severe, although stem cell transplants from donors have been available for a number of years, if a match can be found.
The UK’s National Health Service announced in late January that Casgevy would be made available in England to patients with sickle cell disease.
Reports have indicated that Casgevy treatment can cost £1.65 million (Dh7.63 million), although the amount the UK's NHS is paying has not been disclosed. The treatment is expensive because it is individualised, with a patient’s own stem cells gene-edited before they are transplanted back. The cost is balanced against Casgevy being designed to be given only once, although patients may need to be treated for side effects such as bleeding.
“With progress and the economies of scale you will eventually see that the price comes down,” Dr Bharat Pankhania, of the University of Exeter Medical School in the UK, said. “But the progress is that we’ll be able to do more things for other gene disorders. People born with genetic disorders, which are a lifelong affliction, can actually have genetic errors cancelled or reversed.”
