Eton licenses ASN-001 topical gel to expand infantile hemangioma portfolio

On July 31, 2026, Eton Pharmaceuticals entered into a license agreement for the late-stage rare disease candidate ASN-001, a timolol topical gel, from Auson Pharmaceuticals for treatment of proliferating superficial infantile hemangiomas.¹ Eton agreed to pay Auson a $3.0 million upfront license fee within thirty days of signing.¹

The candidate is aimed at a different segment of the hemangioma population than Eton's existing product. ASN-001 is being developed for proliferating superficial infantile hemangiomas.¹ In a prior study, Auson had completed a three-arm Phase II/III trial in 168 patients, finding that 56% of patients on a twice-daily regimen and 42% on a three-times-daily regimen reached elimination or near-elimination of their hemangiomas by week 24, versus 15% in the placebo arm.¹

Eton plans further testing before filing. The company will conduct a bioavailability bridging study, and if that succeeds, intends to submit an NDA once the study is complete in the second half of 2027.¹

If approved, additional payments would follow. Eton would owe Auson $5,000,000 upon first commercial sale, plus sales-based milestones of $1,000,000 at $20,000,000 in annual net sales, $2,500,000 at $40,000,000, $5,000,000 at $80,000,000, $10,000,000 at $150,000,000, and $10,000,000 at $280,000,000.¹ Royalties to Auson would be tiered at 10% up to $200,000,000 in net sales, 13% between $200,000,000 and $400,000,000, and 15% above $400,000,000, calculated on cumulative lifetime sales.¹

Eton estimated the addressable population broadly. The company estimates more than 10,000 patients currently use off-label ophthalmic timolol for infantile hemangiomas, with a total market opportunity of 20,000 to 30,000 patients for an approved product.¹ ASN-001 carries patent protection through 2044, with an additional application pending.¹