29 January 2018
ByAppeared in BioNews 935
The Wall Street Journal has found evidence of 11 genome editing clinical trials in China, geared towards targeting an array of cancers and HIV infection. One is reported to have started as early as 2015.
US researchers were the first to use CRISPR to edit DNA. However, genome-editing trials have yet to be approved in the country. China, by contrast, has much less intensive regulation in this area.
'China shouldn't have been the first one to do [a human genome editing trial],' Dr Shixiu Wu, who is leading one of China's first such trials at Hangzhou Cancer Hospital, told the Wall Street Journal. 'But there are fewer restrictions.'
Researchers from University of Pennsylvania in the USA are yet to receive final regulatory clearance for CRISPR-based cancer therapeutics. Dr Wu's trial is using genome editing to treat oesophageal cancer. The team aims to edit the genome of immune T cells extracted from patient blood to halt the production of PD-1, a protein which helps cancer cells evade the immune system, before reinfusing the modified cells into the patients.
The report also highlighted instances of less stringent, sometimes inconsistent review processes for human trials faced by Chinese researchers compared with their Western counterparts. The latter must field hospital review boards, ethics committees and government agencies before receiving approval.
Dr Carl June, lead scientist from the University of Pennsylvania study, spoke of regulatory asymmetry between the USA and China. 'We are at a dangerous point in losing our lead in biomedicine. It is hard to know what the ideal is between moving quickly and making sure patients are safe.'
Despite its purported efficacy and ease of use in laboratory-based studies, CRISPR research faces concerns regarding unintended alterations within DNA ('off-target' effects, see BioNews 903), or even rejection by the patient's immune system (see BioNews 933).
Calling CRISPR a double-edged sword, Dr Wu said: 'If we don't try, we will never know.'