Ugandan scientists study new sickle cell gene therapy

Government-owned research organisation, Joint Clinical Research Centre (JCRC), has said a newly approved gene therapy that aims to cure sickle-cell disease, gives Ugandan scientists momentum to develop the same therapy locally.  

Dr Cissy Kityo, the JCRC executive director, said this while commenting on the gene therapy, Casgevy, which has been approved by the United Kingdom for use.

“Gene therapy is the frontier of medicine today. Right now, there are two products, both gene therapies to cure Sickle Cell Disease (SCD). These have been approved in the United States and one has been approved in the United Kingdom (UK),” she said.

The UK government said in its November 16 statement that the new treatment, Casgevy, “for sickle-cell disease and transfusion-dependent beta-thalassemia (TDT) has been authorised by the Medicines and Healthcare Products Regulatory Agency (MHRA) for patients aged 12 and over after a rigorous assessment of its safety, quality and effectiveness”. 

The UK government added: “Casgevy is the first medicine to be licensed that uses the innovative gene-editing tool CRISPR, for which its inventors were awarded the Nobel Prize in 2020.”  

Beta thalassemia, according to scientists, is an inherited blood disorder in which the part of the red blood cell, haemoglobin, that carries oxygen throughout the body, is inadequate. People with severe forms of the disorder rely on constant transfusion of blood from people without the disease, every three or five weeks, to remain alive. 

Beta-thalassemia mainly affects people of Mediterranean, South Asian, Southeast Asian and Middle Eastern origin, according to researchers. Both beta-thalassemia and SCD are genetic conditions caused by errors in the genes for haemoglobin.

Dr Kityo said sickle cell disease is highly prevalent in Sub-Saharan Africa (SSA) where Uganda is located and such a product raises hope. 

Around 20,000 children are born with the disease yearly and over 250,000 Ugandans currently have sickle cell disease, according to Health Ministry data.  Of the children with the disease, about 50 percent to 80 percent, health experts say, die before reaching their fifth birthday partly because of gaps in care.

The UK MHRA explained that Casgevy is designed to work by editing the faulty gene in a patient’s bone marrow stem cells so that the body produces functioning haemoglobin. 

“To do this, stem cells are taken out of bone marrow, edited in a laboratory and then infused back into the patient after which the results have the potential to be life-long,” the regulator said in a statement. 

Dr Kityo is, however, concerned that many people in the continent may not afford the therapy.
“Uganda ranks fourth as the country with the highest SCD in SSA. These products (gene therapy) are certainly very expensive and out of reach for populations in Africa and Uganda,” she said. 

Casgevy could cost as much as “$2 million” ( about Shs7.6b) “per patient,” according to information from Nature Biotechnology, a subsidiary of Nature, a British scientific journal. 

Dr Kityo also said: “JCRC has been engaged in this journey since 2020, we have mobilised experts in the world to help us in this work.”

She added that around $20 million (Shs75.1b) would be required for this initiative to take off in Uganda.