Gene-Therapy Trial Shows Promise Fighting ‘Bubble Boy’ Syndrome

A new gene-therapy treatment is showing promise in treating a rare and severe congenital condition that involves extreme immune-system deficiencies.

“Bubble boy” syndrome, an X-linked condition, takes its name from a famous case in which an affected boy, vulnerable to infection, lived inside a plastic bubble that protected him from the world’s germs. Outside of such sterile environments, babies with the syndrome seldom live longer than a year, the Wall Street Journal reports.

The condition has for decades bested medical researchers, despite occasional bouts of optimism — hope for one previous gene-therapy treatment was felled when some recipients developed leukemia.

Gene-therapy treatment works, essentially, by replacing unperforming genes with functional ones. Dysfunctional cells are removed from the child’s immune system and exposed to a genetically engineered virus that can reprogram the cells to function properly, explains Reuters. Those cells are then reinserted back into the patient.

In the earlier treatment, the virus to which the cells were exposed apparently activated a part of their genetic code that leads to leukemia, Reuters says.

But initial results reported in the New England Journal of Medicine show that none of the nine babies from the U.S. and Europe who received the latest treatment are exhibiting any signs of cancer.

Of the nine infant participants in the research — who were between 4 and 10½ months old when they began receiving the therapy — eight were still alive 16 to 43 months later, without living in a protective “bubble.” (The ninth child died four months after treatment began from an earlier infection he had been fighting.)

Out of the eight boys still living, the treatment upped blood T-cell levels, rebuilding the immune system, of seven. In the case of the eighth child, the treatment did not rebuild his immune system, but a successful stem-cell transplant has kept him in improved health, Reuters reports.