June 29, 2022

Progress for gene therapy

Hopes for gene therapy rewarded by recent studies

After years in the wilderness, gene therapy may be about to make a comeback. In an editorial in the leading journal Science, Italian researcher Luigi Naldini says “Gene therapy has recently had some important successes in treating severe inherited diseases after years of skepticism from the scientific community and neglect by the pharmaceutical industry

Three recent breakthroughs may indicate that gene therapy is a viable option for patients. Gene therapy involves the removal, modification and then reinsertion of a patient’s genes. It can be hazardous. In 1999 an 18-year-old American, Jesse Gelsinger, died in a clinical trial. Six years ago, 20 children in France were treated. At first, the treatment seemed successful, but 3 developed leukaemia and 1 died.

Nonetheless, three modest recent successes have put gene therapy back in the game. One of these treated children suffering from a fatal brain condition, one was used to treat a rare form of blindness, and another was given to children suffering from a condition causing the deterioration of the immune system.

A recent paper in the journal Science documented the successful treatment of two boys with adrenoleukodystrophy, or ALD, a condition causing the deterioration of the fatty insulation surrounding nerve cells. The ultimately fatal disease leads to progressive brain damage and death between 2 and 5 years following diagnosis. The disease was arrested rather than cured, but the results were promising.

The process that was used for the two boys involved removing bone marrow, then infecting the marrow with a virus designed to carry a properly functioning copy of the ALD gene. This achieved similar results to the more traditional bone marrow transplant method, which requires a perfect match, usually from a patient’s sibling. ~ New York Times, Nov 5, London Times, Nov 6; Science, Nov 6

Jared Yee
gene therapy