Why Did ARWR Stock Surge Over 15% Pre-Market Today?

The preliminary results from Phase 1/2a clinical trials of the company’s RNA interference (RNAi) therapies suggest the treatments may reduce body fat and improve metabolic health in patients, particularly those with type 2 diabetes.

• The interim data show that ARO-INHBE, especially when combined with tirzepatide, doubled weight loss and tripled reductions in visceral fat.
• In adults with obesity, a single 400 mg dose of ARO-INHBE reduced serum Activin E by a mean of 85%, reaching a maximum reduction of 94%.
• ARO-ALK7 became the first RNAi therapy to silence an adipocyte gene in humans.

Arrowhead Pharmaceuticals Inc. (ARWR) stock jumped over 15% in Tuesday’s premarket, after it released early data from its Phase 1/2a clinical trials of its RNA interference (RNAi) therapies, ARO-INHBE and ARO-ALK7, targeting obesity. 

The preliminary results suggest these investigational treatments may reduce body fat and improve metabolic health in patients, particularly those with type 2 diabetes.

Promising Fat Reduction

The interim data show that ARO-INHBE, especially when combined with tirzepatide, a GLP-1/GIP receptor co-agonist, doubled weight loss and tripled reductions in visceral fat, total fat, and liver fat compared with tirzepatide alone.

The findings mark the first human evidence that targeting the Activin E/ALK7 pathway could enhance weight loss beyond that achieved by existing incretin therapies. In adults with obesity, a single 400 mg dose of ARO-INHBE reduced serum Activin E by a mean of 85%, reaching a maximum reduction of 94%.

On Stocktwits, retail sentiment around Arrowhead stock jumped to ‘bullish’ from ‘bearish’ territory. Message volume shifted to ‘high’ from ‘low’ levels in 24 hours. 

Clinical Highlights

ARO-INHBE monotherapy at week 16 led to a 9.9% reduction in visceral fat, a 38% drop in liver fat, and a 3.6% increase in lean muscle. Two doses at week 24 further improved visceral fat reduction to 15.6% after adjusting for placebo. 

Combined with tirzepatide, ARO-INHBE achieved roughly double the weight loss and triple the fat reduction compared to tirzepatide alone.

ARO-ALK7 became the first RNAi therapy to silence an adipocyte gene in humans, reducing ALK7 mRNA in fat tissue by an average of 88% at the 200 mg dose, with a peak reduction of 94%. Early data also showed a 14.1% reduction in visceral fat after a single dose at week 8, adjusted for placebo.

ARWR stock has gained over 227% in the last 12 months. 

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