Arctic Bioscience (ABS) Study Result summary

Study design and objectives

• The HeROPA phase IIb trial enrolled 521 patients with mild-to-moderate psoriasis for a 52-week, international, multicenter, placebo-controlled study.

• The primary endpoint was PASI 50 at 26 weeks, with secondary endpoints and safety assessed at 52 weeks, including PASI, BSA, sPGA, SCPGA, and quality of life.

• Three treatment arms were used: two HRO350 doses and placebo.

• The study design addresses natural disease fluctuations and high placebo response by maintaining a year-long placebo control.

• Protocol was developed with EMA scientific advice and is approved in the UK, Germany, Poland, Finland, and Norway.

Mechanism of action and preclinical findings

• HRO350 is a first-in-class oral drug with phospholipid esters from herring roe (PEHERO) as the active ingredient.

• The API promotes specialized pro-resolving mediator (SPM) biosynthesis, supporting resolution—not just inhibition—of inflammation.

• Cellular studies show HRO350 modulates the IL-17/23 axis, indicating immunomodulatory and anti-psoriatic effects.

• Preclinical data support a shift in macrophage phenotype toward protective and reparative states.

• SPMs are key in shifting immune response from inflammation to resolution, a novel therapeutic approach.

Key findings and results

• The primary endpoint (PASI 50 at 26 weeks) was not met due to a higher-than-expected placebo response.

• High-dose HRO350 showed a response rate close to the estimated effect, but no statistical difference from placebo.

• No safety concerns or unexpected serious events related to the study medication have been reported.

• PASI50 was used as the primary endpoint to align with regulatory guidelines for psoriasis studies.

• All participants completed 6 months of treatment; the study continues for 52 weeks.