Skyrizi (risankizumab-rzaa) for the Treatment of Plaque Psoriasis

Skyrizi™ (risankizumab-rzaa) is a monoclonal antibody (mAb) indicated for the treatment of moderate-to-severe plaque psoriasis in adult patients.

Drug Name

Skyrizi™ (risankizumab-rzaa)


Boehringer Ingelheim and AbbVie

Therapy Class

Monoclonal antibody

Product Description

Selective Interleukin-23 (IL-23) inhibitor


Skyrizi (risankizumab-rzaa) is a monoclonal antibody (mAb) indicated for the treatment of moderate-to-severe plaque psoriasis in adult patients.

The drug is jointly developed and marketed by AbbVie and Boehringer Ingelheim under an agreement signed in March 2016.

AbbVie made an upfront payment of $595m for the drug and holds global development and commercialisation rights. Boehringer Ingelheim holds co-promotion rights for the drug in an asthma indication and is eligible to receive milestone payments and royalties on sales.

The drug received orphan drug designation from the US Food and Drug Administration (FDA) for the treatment of Crohn’s disease in paediatric patients in November 2016. It is being studied for ulcerative colitis treatment.

Skyrizi was first approved in Japan for the treatment of plaque psoriasis, generalised pustular psoriasis, erythrodermic psoriasis and psoriatic arthritis in adult patients in March 2019. It was approved in the US, Canada and Europe in April 2019 for the treatment of plaque psoriasis.

Skyrizi injection is available as a sterile, colourless to slightly yellow, opalescent solution. It is marketed in a 1ml glass syringe, attached to a 29 gauge, 0.5in needle and needle guard.

Plaque psoriasis causes and symptoms

Plaque psoriasis is a common autoimmune inflammatory disorder that occurs due to the accelerated development of cells on the surface of the skin. The disease leads to the formation of dry, itchy and often painful red patches of dead skin cells on different parts of the body.

“IL-23 cytokine is responsible for inflammatory and immune responses.”

The condition is estimated to affect 125 million people worldwide. Some common symptoms are red, thick lesions with silvery scales, itching, soreness, swollen joints and cracked skin that often bleeds.

Skyrizi’s mechanism of action

Skyrizi is a humanised immunoglobulin G1 (IgG1) mAb, which selectively binds to IL-23 cytokine and blocks its interaction with the IL-23 receptor.

Naturally occurring in the human body, the IL-23 cytokine is responsible for inflammatory and immune responses.

Clinical trials on Skyrizi

The FDA and European Commission’s approvals were based on the positive outcomes of AbbVie’s global Phase III psoriasis programme, which included four multi-centre, randomised, double-blind clinical trials named ULTIMMA-1, ULTIMMA-2, IMMHANCE and IMMVENT.

A total of 2,109 patients with moderate-to-severe plaque psoriasis were enrolled in the studies to evaluate the efficacy and safety profile of the drug compared to placebo. The co-primary endpoints of the studies were Psoriasis Area and Severity Index (PASI 90) representing a 90% reduction and a static Physician Global Assessment (sPGA) score of either zero representing clear or one representing almost clear at 16 weeks.

At 52 weeks into the ULTIMMA-1, and ULTIMMA-2 trials, 82% and 81% of patients treated with Skyrizi achieved PASI 90 scores respectively, while 56% and 60% patients respectively achieved PASI 100 scores. Patients treated with Skyrizi achieved 58% and 60% sGPA zero scores in the trials, respectively.

The overall analysis of the results from the ULTIMMA-1 and ULTIMMA-2 trials highlighted the achievement of PASI 90 by 88% of the Skyrizi-treated patients and PASI 100 by 80% of Skyrizi-treated patients at week 16, which was maintained at one year.

In the IMMHANCE trial, the patients who achieved either sPGA zero or one were randomised again to continue Skyrizi at week 28. At week 52, 87% of the patients maintained the response, while 61% withdrew from the trial.

In the IMMVENT clinical trial, the drug showed superior results than adalimumab. PASI 90 was achieved in approximately 72% of Skyrizi-treated patients compared to 47% of those treated with adalimumab at week 16.

The most common adverse events reported by the patients during the clinical trials were upper respiratory infections, fatigue, injection site reactions and tinea infections.

Related Projects