A randomized, double-blind, placebo-controlled clinical study to investigate the efficacy of herring roe oil for treatment of psoriasis

The effect of omega-3 polyunsaturated fatty acid supplements in patients with psoriasis vulgaris has previously been investigated, but interventions varied in source, composition, dose, administration route and duration of treatment. The observed beneficial effects in patients with psoriasis vulgaris using herring roe oil as a dietary supplement prompted this investigation. This randomised, double-blind and placebo-controlled study was designed and performed to explore the efficacy and safety of herring roe oil supplementation in 64 patients with plaque psoriasis (ClinicalTrials.gov: NCT03359577). The primary end-point was comparing the change in mean Psoriasis Area Severity Index (PASI) scores in the herring roe oil treatment group and the placebo group from baseline to week 26. In the intention-to-treat population, a statistically significant improvement in the mean PASI score was observed with herring roe oil compared to placebo at 26 weeks. In the recruited patient group, the measured improvement was greatest in patients with a PASI score from 5.5–9.9 at baseline.