Participants involved in the trials, which are ongoing, experienced side effects including nausea, fatigue, fever and an increased risk of infection, but no significant safety concerns were identified. The MHRA and manufacturer are monitoring the safety of the technology and will release further results.
One concern surrounding the approach is that CRISPR can sometimes make unintended genetic modifications with unknown side effects.
“It is well known that CRISPR can result in spurious genetic modifications with unknown consequences to the treated cells,” geneticist David Rueda at Imperial College London told the SMC. “It would be essential to see the whole-genome sequencing data for these cells before coming to a conclusion. Nonetheless, this announcement makes me feel cautiously optimistic."
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