- A new gene therapy offered hope for a cure against hemophilia B, a genetic clotting disorder.
- One patient called an experimental treatment a “miracle” that changed his life.
- But it is still in the early phases of development and a patient association has called for caution.
A new gene therapy has offered hope for a cure for hemophilia B patients.
The 26-week trial took place in 2020. By its end, nine of 10 patients that received the one-off treatment no longer needed regular injections to treat the condition.
The treatment is still in very early stages of development and ten people is a small sample size. But a doctor who developed the treatment was optimistic about its wider potential, saying that it could cure most adults with hemophilia B within three years, per the BBC.
A patient association described the results as encouraging but said that more research was needed before using it more widely. Experts on chronic conditions are often wary of talking about “cures” in their early stages for fear of giving false hope.
Hemophilia B is a genetic condition that affects blood clotting. It means people with the condition will bleed for longer. In severe cases, it can cause spontaneous bleeding into the organs and joints.
To counteract these effects, patients are given regular injections of material to help their blood clot, a cumbersome process.
Elliot Mason, a patient in the trial, told the BBC he felt like he grew up “anxious of getting hurt.” At one point, he had to receive an injection every other day, the BBC reported.
Mason received the treatment as part of the clinical trial. He said he hasn’t needed an injection since and has taken up skiing and motorbiking.
“My life is completely normal, there’s nothing that I have to stop and think ‘how might my haemophilia affect this?’,” he told the BBC.
“It’s all a miracle really, well it’s science, but it feels quite miraculous to me,” he said.
The treatment works by delivering several copies of the gene that codes for the clotting factor to liver cells. It gives the body the blueprints to make the protein itself instead of needing it from an external source.
The theory is that a single injection of the gene treatment could treat the condition for years or decades. Receiving the treatment took about an hour, Mason told the BBC.
Trial participants received doses of varying strengths alongside immunosuppressants.
Per the trial results, five of the ten patients had normal levels of blood-clotting material after the treatment. Three had increased levels, but still less than what is considered normal.
One had abnormally high levels of factor IX which led to the development of a blood clot, per the New England Journal. One patient saw his levels decrease over the 26 weeks and had to resume injections.
Prof Pratima Chowdary, a hematologist at the Royal Free Hospital and University College London and lead author on the study, told the BBC she thought most adults with hemophilia B could be cured within three years.
“Removing the need for hemophilia patients to regularly inject themselves with the missing protein is an important step in improving their quality of life,” Chowdary said in a press release.
Clive Smith, chairman of the UK-based patient association Haemophilia Society, was more cautious: “This initial data is promising, but we continue to monitor gene therapy trials closely and cautiously, as with all new treatments,” the BBC reported.
The trial participants agreed to be followed for another 15 years to check on how long the treatment would last and to monitor potential effects that may emerge later, according to an accompanying press release.
The treatment was not been tested on children, whose livers are still developing until age 12, per the BBC.
The next step in pharmaceutical product development is typically to test the product on a wider set of people in what is known as a Phase III trial.
