An experimental therapy being developed by AbbVie for the treatment of patients with moderate to severe plaque psoriasis has hit key targets in a pivotal late-stage trial.

Risankizumab works by selectively blocking interleukin-23 (IL-23) - a key signalling agent that has been linked to a number of chronic immune-mediated diseases.

The drug, to which AbbVie bought rights to from Boehringer Ingelheim in 2015, is also being investigated in other immunological disorders, such as Crohn’s disease, psoriatic arthritis and asthma.

Top-line results from IMMhance, the fourth Phase III trial evaluating risankizumab for the treatment of patients with moderate to severe plaque psoriasis, showed that after 16 weeks’ treatment the co-primary endpoints of at least a 90 percent improvement in the Psoriasis and Severity Index (PASI 90) and a static Physician Global Assessment (sPGA) score of clear or almost clear (sPGA 0/1) versus placebo were met.

At week 16, 73 percent of patients receiving risankizumab achieved PASI 90 compared to two percent of those given a placebo. An sPGA 0/1 was achieved by 84 percent of risankizumab patients compared to seven percent of placebo patients.

Also, results showed that 47 percent of those receiving risankizumab achieved PASI 100 versus one percent of patients in the placebo arm, while 46 percent achieved an sPGA 0 compared to one percent, respectively.

In the second phase of the study, the primary endpoint of sPGA 0/1 at week 52 (one year) was also met, the firm noted.

"The significant rates of skin clearance achieved at week 16 are very encouraging for patients with moderate to severe plaque psoriasis," said Andrew Blauvelt, dermatologist and president of Oregon Medical Research Center and the lead investigator for the study.

"These data also indicate that continuous treatment with risankizumab has the potential to deliver better disease improvement for patients over time when compared to withdrawing them from therapy after an initial response."