Intellia Therapeutics (NTLA) Study Update summary

Study design and methodology

• Phase 2 was a randomized, double-blind, placebo-controlled, international, multicenter study with 27 adults aged 18–76 with hereditary angioedema (HAE) types I and II, evaluating safety, efficacy, and dose selection.

• Participants discontinued prior prophylactic therapies before dosing and received a single intravenous dose of NTLA-2002 (25 mg or 50 mg) or placebo.

• The primary endpoint was the number of HAE attacks per month during a 16-week observation period; secondary endpoints included safety and plasma kallikrein reduction.

• The study also evaluated pharmacodynamics and pharmacokinetics.

Efficacy results

• Both 25 mg and 50 mg single doses led to deep, durable reductions in plasma kallikrein and HAE attacks, with the 50 mg dose achieving up to 86% mean reduction in kallikrein and 77–81% reduction in attack rates versus placebo.

• Eight of 11 patients (73%) in the 50 mg arm were completely attack-free during and beyond the 16-week period, with 10 of 11 showing clinically meaningful reductions.

• The 25 mg arm showed a 75–80% reduction in attack rates, with four of 10 patients attack-free.

Safety and tolerability

• NTLA-2002 was well tolerated at both dose levels, with most adverse events being mild or moderate, including headache, fatigue, nasopharyngitis, and infusion-related reactions, all resolving without long-term effects.

• No serious adverse events related to NTLA-2002 were reported; one serious event in the placebo arm was attributed to underlying HAE.

• No clinically significant laboratory abnormalities were observed, and no patients discontinued due to adverse events.