Carcinogenic?

CompilationFan Dongdong

Previously, a group of experts called for better research methods to be used in the development of gene therapy, and more closely monitor the side effects of gene therapy

The committee is convened by the U.

Whether gene therapy causes cancer is still doubtful

When discussing potential carcinogenic risks, experts spent a lot of time weighing and analyzing the results of animal experiments, some of which even date back more than 20 years

Earlier this year, when a patient who received an experimental gene therapy for hemophilia developed by the biotech company UniQure was diagnosed with liver cancer, people gradually became concerned about whether the carcinogenic risk of gene therapy would also play a role in humans.

Denise Sabatino, a researcher at the University of Pennsylvania, said at the conference that a study conducted on dogs receiving gene therapy for hemophilia showed that AAV did integrate into the genome of the tested dogs, but did not cause cancer in the dogs participating in the trial

At the same time, members of the FDA team said that longer-term animal testing may be more effective in capturing the potential carcinogenic risk of AAV.

But there are also industry insiders who are reluctant to make extensive recommendations to the FDA because there are currently no rules for all aspects of gene therapy

There are no standards for liver toxicity monitoring

Although the carcinogenic risk of human AAV gene therapy may only exist in theory, liver toxicity is one of the most common side effects reported in clinical trials of gene therapy so far, and in a few cases can cause serious health problems in patients

In a study of gene therapy developed by Audites Therapeutics, three children suffered severe liver damage after receiving very high doses of treatment, and eventually three died unfortunately

Experts call on researchers to more comprehensively screen and assess whether subjects have previously suffered from liver disease.

Lisa Butterfield, chair of the conference and deputy director of the Parker Institute of Cancer Immunotherapy at the University of California, San Francisco, also expressed support for careful screening

In addition, some experts also pointed out that a major dilemma at present is that it is difficult to clarify the composition of the gene therapy dose, because the ingredients may contain substances other than therapeutic DNA

There is a risk, but it is not recommended to limit the dose

At the meeting, the committee also proposed many methods that may make gene therapy trials safer, such as improving the way patients are screened for clinical trials

In this regard, Anthony Davies, the founder and CEO of Dark Horse Consulting, which specializes in gene therapy, said, “Although the conclusions of this meeting are positive signals for preclinical and clinical adverse events in the field of gene therapy, To a large extent, the experts’ suggestions have not touched on the specific measures that may be taken to help the field face the future

Previously, a series of safety incidents in clinical trials of gene therapy have revived concerns about the side effects of gene therapy and the use of high therapeutic doses

Reference source: At FDA meeting, gene therapy experts wrestle with field's blindspots