- Thirteen biopharma companies, including Sangamo Therapeutics and Bluebird bio, signed a statement of principles opposing gene editing of human sperm, eggs or embryos because of the risks of passing on modifications to subsequent generations.
- The statement of principles, released by the Alliance for Regenerative Medicine, supports gene editing of "somatic" cells, which cover most tissues, because most genetically driven diseases can be treated in those cells.
- Genetic editing of germline cells is newly in focus following research by Chinese scientist He Jiankui, who edited the genomes of at least three embryos that were implanted for birth. Jiankui has been fired from his university and detained by the Chinese government.
Unlike most pharmacological interventions, gene therapy raises numerous ethical issues. In most cases, the technology has involved attempts to alter genetic expression in patients to correct for faulty proteins behind disease, research that has resulted in the marketed drugs sold by Spark Therapeutics, Novartis and Bluebird bio.
These use viral vectors or engineered autologous cells to deliver corrected genes into affected tissue, with little risk that the alterations could be passed to subsequent generations because the therapies do not affect "germline cells," or sperm, eggs or embryos.
However, in late 2018 He, a researcher at the Southern University of Science and Technology, announced to the scientific community's shock the birth of twin girls whose genomes had been edited as embryos using CRISPR-based techniques. He said he sought to make the girls resistant to HIV.
As the backlash grew, He was fired from his job and put under house arrest by Chinese authorities.
The 13 gene therapy companies said they are only focusing on somatic tissues and are opposed to germline gene editing.
"Unless and until ethical and potential safety questions with respect to germline gene editing are adequately addressed, we do not support or condone germline gene editing in human clinical trials or for human implantation," they wrote.
The companies said the Food and Drug Administration, European Medicines Agency and other national agencies provide the best framework for regulating the development of gene therapies, and warned against adding additional levels of oversight.
"It is our belief that arbitrary and ancillary oversight bodies or processes may carry the risk of delaying research and development efforts, which in turn would adversely impact afflicted patient populations," the statement of principles reads.
They added they support the work of standards settings bodies, such as the U.S. National Institute of Standards and Technology and International Organization for Standardization, to develop guidelines for identifying off-target effects on tumor suppressors and oncogenes.
James Burns, CEO of Casebia Therapeutics, one of the co-signers, said the call for a moratorium on gene editing of germline cells could be reversed as researchers gain more experience with the technology.
"I think that's one of the things that we still have to talk about: What is that standard that we have to have on the ethical as well as scientific and safety questions?" Burns said in an interview with BioPharma Dive. "I think we'll know when we get there, but it's hard to actually prospectively define it."
Companies signing the statement were Audentes Therapeutics, Bluebird Bio, BlueRock Therapeutics, Caribou Biosciences, Casebia Therapeutics, CRISPR Therapeutics, Editas Medicine, Homology Medicines, Intellia Therapeutics, LogicBio Therapeutics, Precision Biosciences, Sangamo Therapeutics and Tmunity Therapeutics.