Researchers have used a CRISPR-based approach to treat a handful of people with transthyretin amyloidosis, a rare inherited disease marked by the buildup of a misshapen protein, NPR reports.
As they report in the New England Journal of Medicine, researchers led by the University College London's Julian Gillmore treated six patients with transthyretin amyloidosis and polyneuropathy with the CRISPR-based therapeutic. The treatment, dubbed NTLA-2001, includes a lipid nanoparticle delivery system directed to the liver that carries a single guide RNA targeting the TTR gene – the gene affected in the condition – and the Cas9 mRNA sequence. The researchers report in their paper that, following treatment, the patients exhibited a decline in their TTR serum protein levels and only experienced mild adverse effects.
The treatment, NPR notes, is the first time a CRISPR treatment has been given systemically to people – other therapies have involved the removal of affected cells, their editing outside the body, and then their return or the application of the therapy directly to affected cells. "This is really opening a new era as we think about gene-editing where we can begin to think about accessing all kinds of different tissue in the body via systemic administration," John Leonard, CEO of Intellia Therapeutics, which sponsored the study, tells NPR.