Agomab’s IPF drug clears first patient test
Agomab Therapeutics' inhaled idiopathic pulmonary fibrosis (IPF) drug AGMB-447 showed lung-restricted exposure and inhibited its intended target in its first patient trial. The company plans to move the ALK5 inhibitor into phase 2 before the end of the year.
Why it matters: TGF-β signaling is an important driver of fibrosis and an attractive target in IPF. AGMB-447 blocks ALK5, a receptor that transmits TGF-β signals into cells, but the inhibition of this pathway throughout the body has been held back by safety concerns.
How it works: Belgian biotech Agomab is trying to address the safety issue by restricting ALK5 inhibition to the lungs. AGMB-447 is inhaled directly into the lung, where it blocks the TGF-β signals that activate fibroblasts and drive the buildup of scar tissue. Any drug that enters the bloodstream is broken down into an inactive metabolite, limiting exposure in the body.
Zoom in: The phase 1 trial tested AGMB-447 in just 10 people with IPF, who received either 4.5 mg or 6 mg twice daily for 14 days. At the 4.5 mg dose, lung concentrations remained high enough to inhibit ALK5, with systemic exposure remaining low. pSMAD3 levels, a downstream marker of the pathway, also fell by more than 50%, showing that the pathway was being inhibited.
On safety: The 4.5 mg dose was generally well tolerated, but Agomab reported more adverse events at 6 mg. Cough and bronchospasm were the most common, although the company reported no new specific or systemic safety signals.
The bigger picture: IPF treatment has expanded after years with few treatment options. Boehringer Ingelheim’s nerandomilast became the first new U.S. approved therapy for the disease in more than a decade in 2025, joining the antifibrotic drugs nintedanib and pirfenidone. Although it is still early, AGMB-447 would bring a different approach and is being developed for use on top of existing treatment.
Reality check: For now, the trial doesn’t tell us whether Agomab’s drug can slow IPF. Only 10 patients received the drug for 14 days, and the study was assessing safety, drug exposure, and target engagement. Clinical efficacy is the next step.
What to watch: Agomab has submitted an application to begin a 120-patient phase 2 trial that will test 4 mg of AGMB-447 twice daily against placebo for 24 weeks, on top of standard treatment. The primary endpoint is change in forced vital capacity, a measure of how much air a person can exhale after taking a full breath.
