(AP) — The lone volunteer in a unique study involving a gene-editing technique has died, and those behind the trial are now trying to figure out what killed him.
Terry Horgan, a 27-year-old who had Duchenne muscular dystrophy, died last month, according to Cure Rare Disease, a Connecticut-based nonprofit founded by his brother, Rich, to try and save him from the fatal condition.
Although little is known about how he died, his death occurred during one of the first studies to test a gene editing treatment built for one person. It's raising questions about the overall prospect of such therapies, which have buoyed hopes among many families facing rare and devastating diseases.
“This whole notion that we can do designer genetic therapies is, I would say, uncertain,” said Arthur Caplan, a medical ethicist at New York University who is not involved in the study. “We are out on the far edge of experimentation."
The early-stage safety study was sponsored by the nonprofit, led by Dr. Brenda Wong at the University of Massachusetts Chan Medical School and approved by the Food and Drug Administration. The hope was to use a gene-editing tool called CRISPR to treat Horgan's particular form of Duchenne muscular dystrophy. The rare, genetic muscle-wasting disease is caused by a mutation in the gene needed to produce a protein called dystrophin. Most people with Duchenne die from lung or heart issues caused by it.
At this point, it's unclear whether Horgan received the treatment and whether CRISPR, other aspects of the study or the disease itself contributed to his death. Deaths are not unheard of in clinical trials, which test experimental treatments and sometimes involve very sick people.
But trials involving CRISPR are relatively new. And Fyodor Urnov, a CRISPR expert at the Innovative Genomics Institute at the University of California, Berkeley, said any death during a gene therapy trial is an opportunity for the field to have a reckoning.
“Step one is to grieve for the passing of a brave human soul who agreed to be basically a participant in an experiment on a human being,” Urnov said. “But then, to the extent that we can, we must learn as much as we can to carve out a path forward.”
FEW ANSWERS YET
A statement from Cure Rare Disease said multiple teams across the country are looking into the details of the trial and its outcome, and the company intends to share findings with the scientific community.
“It will probably be 3-4 months to come up with a full conclusion,” said spokesman Scott Bauman. “At this stage of the game, saying anything is pure speculation.”
The company, which is also working on 18 other therapeutics, said in its statement that the teams' work is essential not only to shed light on the study’s outcome but also “on the challenges of gene therapy broadly.” Meanwhile, it said, “we will continue to work with our researchers, collaborators, and partners to develop therapies for the neuromuscular diseases in our pipeline.”
Bauman said the company has filed a report on the death with the FDA as required. The FDA declined to release or confirm the report.
Sarah Willey, spokeswoman for Chan Medical School, said scientists there provided data to the company for the report. She later emailed to say no one there would comment further; out of respect for the family's wishes, all information would come from Cure Rare Disease. Monkol Lek, a Yale genetics expert who has been collaborating on the effort, did not respond to a request for comment. Yale spokeswoman Bess Connolly asked a reporter for context on the story but didn't respond to a follow-up email or phone call.