Doctors have successfully treated a baby born with a rare genetic condition using gene-editing therapy – marking the first time that gene-editing treatment has successfully repaired a DNA mutation.
KJ Muldoon, born last year, received three infusions of microscopic gene editors that corrected a mutation in his liver.
While doctors will need to monitor him over the next several months to assess the treatment’s effectiveness, the therapy has already partially reversed his condition.
Dr. Rebecca Ahrens-Nicklas, who treated the child, described the therapy to be “really exciting” and stated that “[the child] is a pioneer.”
In an interview, Ahrens-Nicklas said this shows that it is possible to create “transformative treatments” for patients who are out of options.
KJ’s parents are thrilled for their son, who has successfully reached his milestones.
Born With a Rare Genetic Disease
KH was born with carbamoyl phosphate synthetase 1 (CPS1) deficiency, also known as urea cycle disorder.
This rare inherited condition causes toxic levels of ammonia to build up in the body whenever protein is consumed. This can lead to brain damage and, if left untreated, can be fatal.
While medications can help lower ammonia levels, they’re usually only partially effective. The alternative is a liver transplant, but finding a suitable donor can take time and by then, the elevated ammonia levels may have already caused irreversible brain damage.
Gene-Editing Therapy
Doctors have begun using gene-editing therapy to treat certain genetic conditions, such as sickle cell disease. They’re also exploring its potential for other illnesses, including inherited high cholesterol, cancer, and some forms of genetic blindness.
Despite its promise, many doctors and patients are frustrated as pharmaceutical companies do not have strong incentives to develop these therapies, even for conditions that affect millions each year.
In response, researchers have been trying to solve the issue by putting together a template for a group of rare diseases that are similar enough so that a single gene-editing therapy can be adapted for others.
This would mean a shorter regulatory approval process, which will make the treatments more practical.
Dr. Kiran Musunuru, who worked on KJ’s case, believes this marks the first step in a novel type of personalized medicine and that it will transform the way doctors practice medicine.
Highly experimental treatments like the one used on KH often raise sensitive ethical questions, particularly when patients or their families are in desperate situations. However, two independent experts who reviewed the case confirmed that scientists followed the necessary precautions.
KJ was first given a very low dose to minimize the risk of side effects. After closely monitoring his response, doctors administered two additional doses.
So far, he hasn’t experienced any side effects and he’s now able to eat protein and has been steadily gaining weight.
