Janssen has filed its potential new psoriasis therapy guselkumab with the European Medicines Agency, hot on the heels of the drug's submission in the US.

Guselkumab is a human monoclonal antibody that targets the protein interleukin (IL)-23, which is known to play a key role in the development of immune-mediated inflammatory diseases.

Around 14 million people in Europe suffer from psoriasis, a chronic, autoimmune inflammatory disorder that results in the overproduction of skin cells, characterised by raised, inflamed, scaly, red lesions, or plaques, which can cause itching, discomfort and pain.

The drug targets moderate to severe forms of the disease, which accounts for around 20 percent of all cases.

The filing is based on safety and efficacy data gathered from four studies, the Phase III VOYAGE 1, VOYAGE 2 and NAVIGATE trials and the Phase II X-PLORE study.

Data from the VOYAGE 1 trial showed significantly higher proportions of patients receiving guselkumab achieved cleared/minimal disease compared with patients receiving placebo, as defined by at least a 90 percent improvement in the Psoriasis Area Severity Index (PASI 90, near complete skin clearance) and an Investigator's Global Assessment (IGA) score of cleared (0) or minimal disease (1) at week 16, the study co-primary endpoints.

The results show that 85.1 percent of patients taking the drug at weeks 0 and 4 and then every eight weeks achieving cleared (IGA 0) or minimal disease (IGA 1) compared with 6.9 percent of patients receiving placebo. Nearly three-quarters of patients (73.3 percent) achieved a PASI 90 response versus 2.9 percent in the placebo arm.

The trial also included an active comparator arm evaluating guselkumab versus tumour necrosis factor blocker Humira (adalimumab). At week 16, following three injections of guselkumab and ten injections of Humira, significantly higher proportions of patients receiving guselkumab achieved IGA 0/1 and PASI 90 (85.1 percent and 73.3 percent, respectively) compared with those taking Humira (65.9 percent and 49.7 percent, respectively).

At week 24, the proportion of patients who achieved a PASI 90 response was significantly higher in the guselkumab group compared with the adalimumab group (80.2 percent vs. 53.0 percent, respectively), and higher levels of skin clearance in those taking Janssen's drug continued through weeks 24 and 48, the firm said.

On the safety side, serious adverse events were reported in 1.7 percent of patients receiving placebo, 2.4 percent of patients receiving guselkumab and 1.8 percent of patients receiving Humira, while the proportions of patients reporting at least one AE were comparable between the two groups at 73.9 percent and 74.5 percent, respectively.

Despite the recent swell in experimental and newly approved psoriasis therapies, such as Novartis Cosentyx (secukinumab) and Lilly's Taltz (ixekizumab), it is widely anticipated that guselkumab will achieve blockbuster status should it make it to market on both sides of the Atlantic.