Hemophilia A, B gene therapies now at Loma Linda University Health
Hemgenix, SPK-8011 are one-time treatments to restore clotting factors
Loma Linda University Health (LLUH) is now offering the gene therapies Hemgenix (etranacogene dezaparvovec) to people with hemophilia B and SPK-8011 (dirloctocogene samoparvovec), an experimental treatment for hemophilia A.
LLUH’s Center of Excellence Hemophilia Program is structured to ensure that financial constraints don’t prevent access to the therapy, with many patients relying on Medicare or Medicaid.
“Our center’s holistic approach includes extensive infrastructure and safety protocols to handle gene therapy,” Akshat Jain, MD, director of Inherited Bleeding Disorders at Loma Linda University Children’s Health, said in a university news story. “We are one of the few centers in the United States and the only one in [Southern California’s] Inland Empire activated to provide this advanced treatment.”
In hemophilia certain blood clotting factors needed for blood to clot are deficient. In most cases, the disease is caused by mutations in genes that encode a specific clotting factor. In hemophilia A, mutations occur in the F8 gene that provides instructions for making factor VIII (FVIII), while in hemophilia B, the F9 gene that encodes factor IX (FIX) is affected. A clotting factor’s low levels or activity put people with hemophilia at risk of excessive and prolonged bleeding episodes.
Factor replacement therapies are standard hemophilia treatments that provide a functional version of the missing clotting factor to help prevent or reduce the frequency of bleeds. Some patients develop neutralizing antibodies, called inhibitors, against the factors, which can limit the treatment’s effectiveness.
Gene therapies to treat hemophilia
Hemgenix is marketed by CSL Behring and is approved to reduce the risk of bleeding in people with hemophilia B who are on treatments to prevent bleeding episodes, have or have had recurrent life-threatening episodes, or serious spontaneous bleeds. It delivers a working version of the F9 gene called Padua, a naturally occurring form that confers FIX a higher clotting activity, packed into a harmless adeno-associated virus.
The therapy is administered into the bloodstream in a three-hour, one-time infusion. After it’s been administered, it heads toward the liver, where the working F9 gene is taken up and used by liver cells to make their own FIX. By restoring the body’s ability to produce FIX, Hemgenix should increase FIX levels, providing patients with bleeding protection.
“Hemgenix has proven to be transformative for patients. It raises clotting factor levels from less than 1% to around 30-40%, which is a dramatic improvement,” Jain said. “While the normal range is 55% and up, this increase significantly reduces the frequency and severity of bleeding episodes, allowing patients to lead near normal lives.”
SPK-8011 is an experimental gene therapy developed by Spark Therapeutics, now part of Roche, for hemophilia A. It works in a similar way to Hemgenix, but is designed to deliver a shorter, but functional version of the F8 gene to liver cells to restore the production of FVIII to help prevent and control bleeding episodes in hemophilia A patients.
One 18-year-old hemophilia patient being considered for treatment said gene therapy would change his life.
“My life would change dramatically as I would not have to keep getting injections hundreds of times and would be able to be more active without fear of bleeding out,” Edgar Larios said.
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