Many patients with chronic plaque psoriasis who have responded well to risankizumab are likely to maintain a good response over two years of continuous therapy, according to clinical trial results.

In the double-blinded IMMhance trial, patients with stable moderate to severe disease who had received three doses of 150mg risankizumab (at 0, 4 and 16 weeks) and had achieved a static Physicians Global Assessment score of zero or one (sPGA 0/1), were re-randomised either to remain on the therapy every 12 weeks, or to receive placebo injections.

The sPGA score assesses average thickness, erythema and scaling of all psoriatic lesions, with scores ranging from zero (clear) to four (severe). All patients entered the trial with a score of at least three (moderate) and about 80% were scored as severe, the authors noted in JAMA Dermatology.

At 52 weeks, 87% of 111 patients remaining on risankizumab had an sPGA score of zero or one, while  just 61% of 225 randomised to withdrawal of therapy (placebo injections) had this score.