Intellia gets FDA OK to begin first phase 3 trial of an in vivo CRISPR-based therapy in the US

Intellia Therapeutics has received the green light to study its in vivo CRISPR-based gene editing therapy in the U.S., positioning it to start a phase 3 trial of the Regeneron-partnered candidate by the end of the year.

Massachusetts-based Intellia worked with sites in Europe and New Zealand to study the drug candidate, NTLA-2001, in a phase 1 trial. Having shown the candidate may safely reduce levels of misfolded TTR, a protein that drives the rare, life-threatening disease ATTR amyloidosis, the biotech has secured the FDA’s blessing to include U.S. sites in an upcoming phase 3 trial.

Intellia is aiming to start the global phase 3 trial by the end of the year, keeping it on track to achieve the timeline it set out in August. In a statement, Intellia CEO John Leonard, M.D., said the planned study will mark “the first in vivo CRISPR-based candidate to begin late-stage clinical development.” Editas Medicine paused its lead in vivo candidate, EDIT-101, after reporting phase 1/2 data 11 months ago.

The statement about the FDA clearance lacks details of the design of the NTLA-2001 phase 3 trial. David Lebwohl, M.D., chief medical officer at Intellia, gave investors a rough idea of what to expect on a conference call in August, explaining that it will be a “pretty similar” size to Alnylam’s HELIOS-B study.

Alnylam has enrolled 655 ATTR amyloidosis patients in HELIOS-B, a placebo-controlled phase 3 trial that is designed to validate vutrisiran in the indication. The RNAi therapeutic is one of several molecules that are in development or approved for use in ATTR amyloidosis.

BridgeBio Pharma shared phase 3 data on its candidate, acoramidis, earlier this year, while Ionis Pharmaceuticals, Pfizer and other companies are also active in the space. 

Intellia has Regeneron in its corner. Under the terms of the partnership, Intellia is taking the lead on the development and commercialization of NTLA-2001, and Regeneron is covering around 25% of the costs in return for the same share of the profits.