2nd man has gene editing; therapy has no safety flags so far


A second patient has been treated in a historic gene editing study in California, and no major side effects or safety issues have emerged from the first man's treatment nearly three months ago, doctors revealed Tuesday.

Gene editing is a more precise way to do gene therapy, and aims to permanently change someone's DNA to try to cure a disease.

In November, 44-year-old Brian Madeux became the first person to have gene editing inside the body for a metabolic disease called Hunter syndrome that's caused by a bad gene. Through an IV, he received many copies of a corrective gene and a genetic tool to put it in a precise spot in his DNA.

"He's doing well and we were approved to go ahead with the second patient who also is doing well," said Dr. Paul Harmatz of UCSF Benioff Children's Hospital Oakland, who treated both men for the same disease.

At a medical conference in San Diego, Harmatz reported safety results for the first six weeks after Madeux's treatment. Sangamo Therapeutics, the company that makes the gene editing tool called zinc finger nucleases, is testing them for two metabolic diseases and hemophilia, a bleeding disorder.

The company said more safety information and initial results on effectiveness should come by mid-year.

Madeux had dizziness, cold sweats and weakness four days after the treatment but they went away on their own in a day, Harmatz said. Madeux also had a severe cough and a partially collapsed lung, but these were deemed unrelated to the gene therapy because he had had similar problems previously.

Importantly, there were no signs of harm to his liver.

"That's the big worry" because changes in the liver might mean the immune system was fighting the treatment and possibly undermining its effectiveness, Harmatz said.

The liver results were welcome news after some other recent reports caused alarm. A prominent gene therapy scientist, Dr. James Wilson of the University of Pennsylvania, published two studies reporting liver and other serious problems in monkeys and piglets that were given experimental gene therapies. Several had to be euthanized.

The animal studies tested very high intravenous doses of a therapy that used a certain virus to carry the gene into cells. Relatives of this virus are widely used in human gene therapies, but Wilson said he does not believe that the results in animals have any bearing on use of lower doses, different types of the virus, or therapies given in different ways such as a shot.

The results might mean it will be harder to develop gene therapies for some neuro-muscular disorders — higher doses in the animal studies were thought necessary to get the therapy into the brain and throughout muscles.

The Sangamo study that Madeux is in used much lower doses of a different type of the virus.

Wilson said it was important to the field that any safety concerns be published quickly. He helped lead a very early gene therapy experiment that killed a teen in 1999, putting some other studies on hold for years.

An editorial in the journal Human Gene Therapy, which published one of Wilson's animal studies, said gene therapy experiments should not stop because that might deprive patients of potentially life-saving treatments.

In the last year, the first gene therapies were approved in the United States to treat cancer and an inherited form of blindness.

___

Marilynn Marchione can be followed on Twitter: @MMarchioneAP

___

This Associated Press series was produced in partnership with the Howard Hughes Medical Institute's Department of Science Education. The AP is solely responsible for all content.


Reader Comments ...


Next Up in Health

Coupon deals of the week
Coupon deals of the week

Coupon availability and coupon values may vary within different regions or neighborhoods. Colgate Mouthwash This week at CVS, Colgate mouthwash is on sale for $5.99. Use the $2 off one Colgate mouthwash coupon found in most of today’s SmartSource inserts. When you check out, you will also get $1 back in ExtraBucks good off your next purchase...
Are we overprotecting our kids? Recent sports stories suggest we are

Two recent situations from the world of sports raise concerns about how we are overprotecting our kids. The first incident involved Gisele Bundchen, wife of Patriot quarterback Tom Brady. After a heartbreaking loss in the recent Super Bowl, Bundchen tried to console her 5-year-old daughter, Vivian, and 8-year-old son, Ben. “…Daddy won...
D.L. STEWART: New law may help keep Swiss lobsters out of hot water

Adding to its reputation as the most pacifistic of nations, Switzerland has outlawed lobster boiling. As reported this week in USA Today, a law that takes effect March 1 makes it illegal to plunge a live lobster into a pot of boiling water. Violators will be subject to up to three years in prison. The legislation was adopted as a result of research...
5 simple things you can do for the environment and your health
5 simple things you can do for the environment and your health

With climate change predictions coming from scientists on a regular basis, many people are increasingly concerned about their personal impact on the environment. At the same time, who isn't concerned about their health and well-being? While it's a no-brainer that severe pollution and ominous natural disasters can be detrimental to humanity, there...
‘Bad Art’ is good for Champaign County Arts Council
‘Bad Art’ is good for Champaign County Arts Council

URBANA — If beauty is in the eye of the beholder, “Bad Art by Good People” can surprise when non-artists contribute works for a good cause. Voting is underway for Champaign County Arts Council’s seventh annual fundraiser, with 14 local non-artists and one high-profile celebrity contributing works. A dinner and art auction for...
More Stories