by Laura Ungar

This family photo shows Pascazia Mazeze, executive director of the Tanzania Sickle Cell Warriors Organization, with her sons, from left, Ian, Rian and Gian outside their home in Tanzania on April 9, 2023. Ian, who has sickle cell disease, takes hydroxyurea and folic acid for anemia. They’ve helped, but haven’t eliminated pain episodes like the one that put him in the hospital for two weeks in 2023. Credit: Courtesy Pascazia Mazeze via AP

Gautam Dongre's two children in India and Pascazia Mazeze's son in Tanzania live with an inherited blood disorder that turns blood cells into instruments of pain.

Now that new gene therapies promise a cure for their sickle cell disease, Dongre says he's "praying the treatment should come to us."

But experts say the one-time treatment is out of reach in India and Africa—places where the disease is most common. Vast inequities cut much of the world off from gene therapy in general.

While access to all sorts of medicine is limited in developing countries, the problem is especially acute with these therapies, which are among the most expensive treatments in the world.

Beyond their sky-high prices, these therapies are extremely complex to give patients because they require long hospitalizations, sophisticated medical equipment and specially trained doctors and scientists. So far, the two gene therapies for sickle cell have only been approved in wealthier countries: both of them in the U.S., and one in Britain and Bahrain as well.

"The vast, vast majority of patients live in an area where they have no access to this kind of therapy," said Dr. Benjamin Watkins, who treats sickle cell in New Orleans and is also involved in pediatric work internationally. "We as medical professionals, and as a society, have to think about that."

Gautam Dongre, of the National Alliance of Sickle Cell Organizations, sits for a portrait with his daughter, Sumedha, 13, at their residence in Nagpur, India, Wednesday, Dec. 6, 2023. Dongre recalls how his newborn son, Girish, cried constantly from stomach and leg pain. Doctors couldn’t figure out what was wrong and didn’t diagnose him with sickle cell for 2 1/2 years. When Sumedha was born, he and his wife had her tested immediately and learned she had the disease too. Credit: AP Photo/Ajit Solanki

Access to gene therapies was a major focus of this year's international summit on human genome editing in London. A subsequent editorial in the journal Nature said high prices leave low- and middle-income countries "entirely in the lurch" and could stymie progress across the field.

Some scientists worry that new cures won't reach their potential, future treatments may never be invented and the prospect of wiping out diseases like sickle cell will remain a distant dream.

STRUGGLING FOR BASIC TREATMENT

For gene therapy to even be an option, people in developing nations must stay alive long enough to get it. There, sickle cell disease is more likely to disable or kill than in wealthy regions. Late diagnosis is common and basic care can be hard to come by.

While gene therapy "is a huge leap forward … we can't forget about those patients," said Watkins, of Children's Hospital New Orleans.

Sickle cell disease begins its assault on the body at birth, affecting hemoglobin, the protein in red blood cells that carries oxygen. A genetic mutation causes the cells to become crescent-shaped, which can block blood flow and cause problems such as excruciating pain, organ damage and stroke.

This electron microscope image provided by the National Institutes of Health in 2016 shows a blood cell altered by sickle cell disease, top. (National Center for Advancing Translational Sciences (NCATS), National Institutes of Health via AP)

The only other cure is a bone marrow transplant, which must come from a closely matched donor and brings a risk of rejection.

Global estimates of how many people have the disease vary, but some researchers put the number between 6 million and 8 million. It's more common in malaria-prone regions because carrying the sickle cell trait helps protect against severe malaria. More than 1 million people with sickle cell disease live in India, studies show, and more than 5 million are in sub-Saharan Africa.

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