Intellia, Regeneron post 12-month data for gene editing therapy in ATTR amyloidosis
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Intellia Therapeutics (NASDAQ:NTLA) and Regeneron Pharmaceuticals (REGN) said on Friday that their experimental in vivo gene editing candidate NTLA-2001 was found to have a lasting therapeutic effect over 12 months in transthyretin (ATTR) amyloidosis.
The interim readout from the ongoing Phase 1 study included follow-up data from 15 patients with hereditary ATTR amyloidosis with polyneuropathy (ATTRv-PN). They were part of four single-ascending dose cohorts in the Part 1 of the trial .
A mutation in the TTR gene leads to hereditary ATTR amyloidosis that causes liver to produce the abnormal transthyretin (TTR) protein.
Six patients treated with the highest dose of 1.0 mg/kg demonstrated 93% mean and 98% maximum serum TTR reduction by day 28.
Highlights of the results included three patients in the 1.0 mg/kg cohort who have reached nine-month follow-up with no signs of a loss in TTR reduction after a single dose.
Notably, patients in the 0.1 and 0.3 mg/kg cohorts have now reached 12 months of follow-up with a durable response, the companies said, noting that the patients in the 0.3 mg/kg cohort showed an 89% mean serum TTR reduction at 12 months.
The patients have well tolerated the drug throughout the follow-up period, with a median follow-up of 10 months.
Intellia (NTLA) and Regeneron (REGN) noted that most of the side effects were mild, with 73% of patients reporting a maximal adverse event severity of Grade 1.
Noting a similar effect to the 1.0 mg/kg dose, the companies have selected a fixed dose of 80 mg in the ongoing Part 2 of the trial.
Last year, Intellia (NTLA) and Regeneron (REGN) drove gene editing stocks higher as early data from the trial indicated the potential of in-vivo CRISPR genome editing for the first time in humans.