A first-in-the-world phase 3 study of an in vivo CRISPR therapy for hereditary angioedema has reported strong results, raising the prospect of a one-time genetic treatment for a rare condition marked by repeated and potentially dangerous swelling attacks.
The trial, led by researchers at Amsterdam UMC and presented at the annual congress of the European Academy of Allergy and Clinical Immunology in Istanbul, enrolled 80 patients in a double-blind design and compared the CRISPR therapy with placebo. The findings were also published in The New England Journal of Medicine, according to the report.
Large reduction in attacks after a single infusion
According to the study summary, the primary outcome was measured between weeks 5 and 28 after a single intravenous infusion. The active treatment was associated with an 87% relative reduction in attacks. In addition, 62% of treated patients remained attack-free without maintenance therapy, compared with 11% in the placebo group.
Secondary outcomes also favored the treatment arm. The need for on-demand treatment fell by 89%, moderate-to-severe attacks decreased by 91%, and quality-of-life scores improved more than in the placebo group.
Researchers said the trial suggests that a severe chronic disorder may be managed long term with a single intervention rather than continuous preventive medication. The report added that the therapy was generally well tolerated, with mild infusion-related reactions, headache, fatigue and back pain described as the most frequent side effects. No serious adverse events were reported in the treatment group.
What the results could mean for genetic medicine
Investigators said the study may help pave the way for in vivo CRISPR treatments in other hereditary disorders. The report noted that data from 37 participants previously enrolled in phase 1 and 2 studies showed the treatment remained effective and safe four years after administration.
For hereditary angioedema, which can cause recurrent swelling episodes and significant treatment burden, the possibility of a single-dose therapy could mark an important shift in care if regulators ultimately confirm the findings and approve the approach.
For more details on the study announcement, see the report from News-Medical.
