The treatment halts cerebral adrenoleukodystrophy in boys.

In one of the largest trials published to date involving a therapeutic solution targeting a single gene disease, a recent study published in the New England Journal of Medicine found a new gene therapy to treat cerebral adrenoleukodystrophy (CALD), was able to stabilize the disease's progression in 88% of patients.

The clinical trial was conducted by the Dana-Farber Institute, Boston Children’s Cancer and Blood Disorders Center and Massachusetts General Hospital. The study was sponsored by Bluebird Bio, the innovator of Lenti-D, which is the proprietary gene therapy used to treat the disease. This condition primarily affects young boys, often claiming their lives within 10 years. According to Boston Children’s Hospital, who announced the results of the trial, the Lenti-D gene therapy proved effective in halting the progression of the disease.

According to Boston Children’s Hospital, the study found 15 of 17 patients had stable neurologic functioning more than two years on average after the gene therapy. "Although we need to continue to follow the patients to determine the long-term outcome of the gene therapy, so far it has effectively arrested the progress of cerebral adrenoleukodystrophy in these young boys," said the Lead Author of the study David A. Williams, Sr. VP and Chief Scientific Officer for Research at Boston Children's Hospital and President of Dana-Farber/Boston Children's Cancer and Blood Disorders Center. "This is a devastating disease, and we are all quite grateful that the patients and their families chose to participate in the trial."

The X-linked genetic disease causes a build-up of fatty acids that damage the myelin sheaths of nerves and result in adrenal insufficiency. Previously, stem cell transplantation using cells donated by another person had been the only effective therapy for CALD.

"The clinical experience with Lenti-D demonstrates the potential for gene therapy to benefit patients with CALD," said David Davidson, Chief Medical Officer of Bluebird Bio. "Early intervention is important to optimize outcomes, so the recent implementation of newborn screening in many states will improve the ability to provide timely treatment to preserve neurologic function in affected boys."